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Viewing September 2002 — 31 paper(s) from the local store. (Local view only — run without --view to fetch new papers.)
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Also flagged:ironmetabolismoxidecoppersodiumnitroprusside
Journal Article 2002-09-26 ✓ 5 Snippets Muckenthaler M, Richter A, Gunkel N, Riedel D, Polycarpou-Schwarz M, Hentze S, Falkenhahn M, Stremmel W, Ansorge W, Hentze MW.
In-Text Gene Mentions

hemochromatosis protein HFE and by pharmacological iron chelation exhibit the highest degree of relatedness, both for iron-regulatory protein (IRP

hemochromatosis protein HFE

…expression of thehemochromatosisprotein HFE and…

…the hemochromatosis proteinHFEand by pharmacological…

…finding suggests thatHFEexpression directly affects…

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Specialized cDNA-based microarrays (IronChips) were developed to investigate complex physiological gene-regulatory patterns in iron metabolism. Approximately 115 human cDNAs were strategically selected to represent genes involved either in iron metabolism or in interlinked pathways (eg, oxidative stress, nitric oxide [NO] metabolism, or copper metabolism), and were immobilized on glass slides. HeLa cells were treated with iron donors or iron chelators, or were subjected to oxidative stress (H(2)O(2)) or NO (sodium nitroprusside). In addition, we generated a stable transgenic HeLa cell line expressing the HFE gene under an inducible promoter. Gene-response patterns were recorded for all of these interrelated experimental stimuli, and analyzed for common and distinct responses that define signal-specific regulatory patterns. The resulting regulatory patterns reveal and define degrees of relationship between distinct signals. Remarkably, the gene responses elicited by the altered expression of the hemochromatosis protein HFE and by pharmacological iron chelation exhibit the highest degree of relatedness, both for iron-regulatory protein (IRP) and non-IRP target genes. This finding suggests that HFE expression directly affects the intracellular chelatable iron pool in the transgenic cell line. Furthermore, cells treated with the iron donors hemin or ferric ammonium citrate display response patterns that permit the identification of the iron-loaded state in both cases, and the discrimination between the sources of iron loading. These findings also demonstrate the broad utility of gene-expression profiling with the IronChip to study iron metabolism and related human diseases.

Also flagged:Protein tyrosine phosphatasesdeathpolyglutamineneurodegenerative diseasesgreen fluorescence proteinGFP
Journal Article 2002-09-10 ✓ 1 Snippet Wu ZL, O'Kane TM, Scott RW, Savage MJ, Bozyczko-Coyne D.
In-Text Gene Mentions

…truncated mutant huntingtin (Htt) and PC12 cells.…

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Polyglutamine expansion is the cause of several neurodegenerative diseases. An in vitro model of polyglutamine-induced neuronal cell death was developed using truncated mutant huntingtin (Htt) and PC12 cells. Cell death was specifically observed in cells expressing a truncated mutant huntingtin-green fluorescence protein (GFP) fusion protein with 118 glutamine repeats (Gln(118)), as demonstrated by the release of lactate dehydrogenase (LDH). To gain further insights into the mechanisms of polyglutamine expansion-induced cell death, the Affymetrix rat genome array U34A was used to investigate gene expression changes associated with polyglutamine-mediated protein aggregation and cell death. Among the up-regulated genes, the increase of four protein tyrosine phosphatases (PTPs) was further confirmed by real-time quantitative reverse transcription PCR. Protein expression of mitogen activated protein (MAP) kinase phosphatase 1 (MKP1) was also increased as demonstrated by Western blot. Furthermore, phosphorylation of MAP kinase extracellular signal-regulated kinase 1/2 (ERK1/2) was substantially reduced in association with protein aggregation, and two general PTP inhibitors, sodium orthovanadate and bpV(pic), dramatically rescued the cells from polyglutamine-induced cell death. These results suggest that one or more of the PTPs are involved in the polyglutamine-induced cell death.

Also flagged:histonechromatinhistonesAmino acidlinker histone
Journal Article 2002-09-09 ✓ 4 Snippets Koutzamani E, Loborg H, Sarg B, Lindner HH, Rundquist I.
In-Text Gene Mentions

…the affinity oflinker histoneshistones for chromatin…

…stronger association betweenlinker histoneshistones and chromatin…

…Analyses oflinker histoneshistones from chicken…

…of frog erythrocytelinker histoneshistones using reverse-phase…

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The replacement linker histones H1(0) and H5 are present in frog and chicken erythrocytes, respectively, and their accumulation coincides with cessation of proliferation and compaction of chromatin. These cells have been analyzed for the affinity of linker histones for chromatin with cytochemical and biochemical methods. Our results show a stronger association between linker histones and chromatin in chicken erythrocyte nuclei than in frog erythrocyte nuclei. Analyses of linker histones from chicken erythrocytes using capillary electrophoresis showed H5 to be the subtype strongest associated with chromatin. The corresponding analyses of frog erythrocyte linker histones using reverse-phase high performance liquid chromatography showed that H1(0) dissociated from chromatin at somewhat higher ionic strength than the three additional subtypes present in frog blood but at lower ionic strength than chicken H5. Which of the two H1(0) variants in frog is expressed in erythrocytes has thus far been unknown. Amino acid sequencing showed that H1(0)-2 is the only H1(0) subtype present in frog erythrocytes and that it is 100% acetylated at its N termini. In conclusion, our results show differences between frog and chicken linker histone affinity for chromatin probably caused by the specific subtype composition present in each cell type. Our data also indicate a lack of correlation between linker histone affinity and chromatin condensation.

Also flagged:antithrombin IIIthrombinheparinpeptidep-nitroanilidecations
Journal Article 2002-09-01 ✓ 5 Snippets Frost CL, Naudé RJ, Muramoto K.
In-Text Gene Mentions

…Antithrombin III (ATIII) was purified from…

…identity with rabbitATIII(31%).…

…ostrich and humanATIIIwith bovine, human…

…ratio of ostrichATIIIto enzyme, 20…

…(9.66 x 10(-11)M)ATIIIare comparable to…

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A kinetic investigation of ostrich thrombin specificity, its regulation and evolutionary development in comparison to those of other well-characterised species may contribute to the understanding of the structure-function relationships of thrombin. Antithrombin III (ATIII) was purified from ostrich plasma by heparin-Sepharose and Super Q-650S chromatography. It exhibited a M(r) of 59.2K and a pI in the range of 5.2-6.0. The ostrich N-terminal sequence was compared to those of other known species and showed the highest identity with rabbit ATIII (31%). Inhibition studies included the interaction of ostrich and human ATIII with bovine, human and ostrich thrombin. At a 2:1 molar ratio of ostrich ATIII to enzyme, 20 and 40% remaining activity was found for bovine and ostrich thrombin, respectively. Ostrich thrombin exhibited a pH and temperature optimum of 9.0 and 60 degrees C, respectively. Hydrolysis of seven peptide p-nitroanilide substrates by ostrich thrombin revealed D-Phe-Pip-Arg-pNA (k(cat)/K(m)=9.65 microM(-1)s(-1)) as the substrate with the highest catalytic efficiency. The effect of monovalent cations on ostrich thrombin catalysis revealed enhanced activity with Na(+). The calculated K(i) values for the complex formation between ostrich thrombin and ostrich (9.29 x 10(-11)M) and human (9.66 x 10(-11)M) ATIII are comparable to reported results. The results obtained from the present study confirmed that ostrich thrombin and ATIII are closely related to the corresponding molecules of other species in terms of physicochemical and kinetic properties.

Also flagged:Non-alcoholic steatohepatitisironchronic liver diseasecirrhosischronic hepatitis Calcohol
Journal Article 2002-09-01 ✓ 1 Snippet Evans CD, Oien KA, MacSween RN, Mills PR.
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HFE

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<h4>Aim</h4>To investigate the natural history of patients with non-alcoholic steatohepatitis by means of a prospective histological study.<h4>Methods</h4>One thousand five hundred and seventy one patients underwent liver biopsy at the Western Infirmary in Glasgow during the 10 year period 1985 to 1994. All biopsies were reported by a single pathologist: 62 were confirmed as having non-alcoholic steatohepatitis and prospective follow up was conducted in 1999. Repeat liver biopsy was carried out where appropriate to assess disease progression.<h4>Results</h4>Initial biopsy scores for the 62 patients (20 men; mean age at biopsy, 52 years) showed a mean of 1.85, 1.39, and 0.5 for necroinflammation, fibrosis, and iron stores, respectively. Forty six were traceable and invited for review, and 26 attended (six men; mean age at initial biopsy, 49.9 years) at a mean of 8.7 years after the initial liver biopsy. No patients had symptoms or signs of chronic liver disease. Four patients had normal liver function tests, one had cirrhosis; the remaining 21 were invited to have a repeat biopsy. Seven patients agreed, a mean 8.2 years after the initial biopsy, and repeat biopsy scores showed no significant difference over this time period, with mean scores of 1.71 (initial score, 2.14), 1.43 (initial score, 0.71), and 0.14 (initial score, 0) for necroinflammation, fibrosis, and iron stores, respectively.<h4>Conclusion</h4>In this series of patients with non-alcoholic steatohepatitis, with a mean clinical follow up of 8.7 years, and a histological follow up of 8.2 years, there was no evidence of progressive chronic liver injury.

Also flagged:cirrhosisFerritinaspartate transaminaseAST
Journal Article 2002-09-01 ✓ 2 Snippets Beaton M, Guyader D, Deugnier Y, Moirand R, Chakrabarti S, Adams P.
In-Text Gene Mentions

…cirrhosis in C282Y-linkedhemochromatosis.…

…with C282Y homozygoushemochromatosis.…

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The aim of the present study was to examine the predictive accuracy of noninvasive clinical and biochemical variables associated with cirrhosis among patients with C282Y homozygous hemochromatosis. Sixteen clinical and laboratory variables were recorded at the time of diagnosis in 193 Canadian C282Y homozygous patients. All patients underwent percutaneous liver biopsy and 27 (14%) had biopsy specimen-proven cirrhosis. Prediction of cirrhosis was assessed first by univariate regression analysis. Variables significantly related to cirrhosis were then evaluated by stepwise linear multivariate regression. Receiver operating characteristic curve analysis of the most informative variables from multivariate analysis was then used to devise a clinically applicable index for the noninvasive prediction of cirrhosis. This index was then validated in 162 C282Y homozygous patients in France. Ferritin, blood platelets, and aspartate transaminase (AST) level were selected for the clinical index. The combination of ferritin levels of 1,000 microg/L or greater, platelet levels of 200 x 10(9)/L or less, and AST levels above the upper limit of normal led to a correct diagnosis of cirrhosis in 77% of Canadian patients. In the French patients, this led to a correct diagnosis of cirrhosis in 90%. In conclusion, in C282Y homozygous patients, a combination of easily measured laboratory variables (ferritin, platelets, AST) can be used to make the diagnosis of cirrhosis in approximately 81% of cases, reducing the need for liver biopsy.

Also flagged:tryptophanbindingcalcium channelsCa(2+)glutathione S-transferasebeta3
Journal Article 2002-09-01 No Snippets Berrou L, Klein H, Bernatchez G, Parent L.
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The ancillary beta subunits modulate the activation and inactivation properties of high-voltage activated (HVA) Ca(2+) channels in an isoform-specific manner. The beta subunits bind to a high-affinity interaction site, alpha-interaction domain (AID), located in the I-II linker of HVA alpha1 subunits. Nine residues in the AID motif are absolutely conserved in all HVA channels (QQxExxLxGYxxWIxxxE), but their contribution to beta-subunit binding and modulation remains to be established in Ca(V)2.3. Mutations of W386 to either A, G, Q, R, E, F, or Y in Ca(V)2.3 disrupted [(35)S]beta3-subunit overlay binding to glutathione S-transferase fusion proteins containing the mutated I-II linker, whereas mutations (single or multiple) of nonconserved residues did not affect the protein-protein interaction with beta3. The tryptophan residue at position 386 appears to be an essential determinant as substitutions with hydrophobic (A and G), hydrophilic (Q, R, and E), or aromatic (F and Y) residues yielded the same results. beta-Subunit modulation of W386 (A, G, Q, R, E, F, and Y) and Y383 (A and S) mutants was investigated after heterologous expression in Xenopus oocytes. All mutant channels expressed large inward Ba(2+) currents with typical current-voltage properties. Nonetheless, the typical hallmarks of beta-subunit modulation, namely the increase in peak currents, the hyperpolarization of peak voltages, and the modulation of the kinetics and voltage dependence of inactivation, were eliminated in all W386 mutants, although they were preserved in part in Y383 (A and S) mutants. Altogether these results suggest that W386 is critical for beta-subunit binding and modulation of HVA Ca(2+) channels.

Also flagged:hereditary hemochromatosisHHironcysteinetyrosinemajor histocompatibility class I-like transmembrane protein
Journal Article 2002-09-01 ✓ 4 Snippets Moalem S, Percy ME, Kruck TP, Gelbart RR.
In-Text Gene Mentions

About 80% of individuals of European descent with HH are homozygous for a cysteine-to-tyrosine substitution (C282Y) in the gene now called HFE.

…gene now calledHFE.…

…The function ofHFEprotein, a major…

…of expression ofHFEon the cellular…

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Hereditary hemochromatosis (HH) is a disorder associated with progressive iron overload and deposition in multiple organs. It is the most common inherited single gene disorder in people of Northern and Western European descent. About 80% of individuals of European descent with HH are homozygous for a cysteine-to-tyrosine substitution (C282Y) in the gene now called HFE. The function of HFE protein, a major histocompatibility class I-like transmembrane protein, has not been fully elucidated. Three consequences of the C282Y mutation are lack of expression of HFE on the cellular surface, a lowered iron level in macrophages, and an increased rate of clearance of iron from the intestinal lumen. These changes could confer protection against certain pathogens early in life before iron overload occurs. Furthermore, the C282Y mutation might have been selected for during the European plagues caused by Yersinia spp. and other pathogens because of the conferred resistance to infection, i.e., by epidemic pathogenic selection.

Also flagged:hereditary hemochromatosisHLAironalcoholglucose
Journal Article 2002-09-01 ✓ 5 Snippets Moirand R, Guyader D, Mendler MH, Jouanolle AM, Le Gall JY, David V, Brissot P, Deugnier Y.
In-Text Gene Mentions

HFE based re-evaluation of heterozygous hemochromatosis.

Homozygosity for the C282Y mutation in the HFE gene is strongly associated with hereditary hemochromatosis.

…re-evaluation of heterozygoushemochromatosis.…

…mutation in theHFEgene is strongly…

…expression of heterozygoushemochromatosisare applicable to…

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Homozygosity for the C282Y mutation in the HFE gene is strongly associated with hereditary hemochromatosis. More than one subject out of 10 in the general population is a heterozygote for the C282Y mutation. In this study, we address whether or not conclusions drawn from HLA-based family studies regarding the expression of heterozygous hemochromatosis are applicable to C282Y heterozygotes. The correlation between HLA-inferred and HFE genotypes and the variation of serum iron tests according to HFE genotype and other factors were studied in persons from well-characterized hemochromatosis pedigrees. Subjects were tested for both C282Y and H63D mutations. The following factors were studied: age, sex, alcohol consumption, body mass index, liver function tests, serum lipids and glucose, serum iron, transferrin saturation, and ferritin. HLA-inferred heterozygotes were C282Y heterozygotes in only 70% and compound heterozygotes (i.e., heterozygotes for both C282Y and H63D) in 20%. C282Y heterozygotes did not differ from wild type homozygotes in terms of serum iron tests. Only compound heterozygotes presented with slightly increased transferrin saturation. On the other hand, increased serum ferritin was strongly associated with overweight or lipidic or glucose abnormalities. C282Y heterozygotes selected from family studies do not have greater serum iron tests than wild type homozygotes, except for compound heterozygotes, and therefore should not require special followup. The discovery of abnormal iron tests in a C282Y heterozygote should lead to workup for other causes of iron overload.

Also flagged:neuronal migrationextracellularsignal transductionaxonaxon guidanceRho
Journal Article 2002-09-01 No Snippets Park HT, Wu J, Rao Y.
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Our understanding of neuronal migration has been advanced by multidisciplinary approaches. At the cellular level, tangential and radial modes of neuronal migration contribute to different populations of neurons and have differential dependence on glial cells. At the molecular level, extracellular guidance cues have been identified and intracellular signal transduction pathways are beginning to be revealed. Interestingly, mechanisms guiding axon projection and neuronal migration appear to be conserved with those for chemotactic leukocytes.

Also flagged:papillary renal cell carcinomaPRCCtumorsMETTFE3chromosome
Journal Article 2002-09-01 No Snippets Sanders ME, Mick R, Tomaszewski JE, Barr FG.
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The molecular genetic correlates of a recently proposed subclassification of papillary renal cell carcinoma (PRCC) that designates tumors as type 1 and type 2 based on histological features have not yet been established. Alterations of known genes in PRCC include missense mutations in the MET oncogene (7q31) and rare translocations fusing TFE3 at Xp11.2 with a variety of other loci. Previous cytogenetic and allelic loss studies of PRCC cases revealed gain of chromosome 3q, 7, 8, 12q, 16, 17, and 20q, and loss of 1p, 6q, 9p, 11p, 13q, 14q, 18, 21q, X, and Y. We analyzed a series of sporadic type 1 and type 2 PRCC cases for MET mutations, TFE3 rearrangements, and allelic imbalance (AI) on 3p, 6, 7q, 9p, 11, 13q, 14q, 17q, 18, 20q, and 21q and compared selected results with a series of conventional renal cell carcinomas. A somatic mutation M1149T was identified in MET exon 17 in 1 of 35 PRCC cases whereas TFE3 rearrangements were not detected in 22 PRCC cases examined. Significant differences in AI frequency between PRCCs and conventional renal cell carcinoma cases were seen on 3p (37.5% versus 77.8%, P = 0.01), 7q (42.9% versus 5.6%, P = 0.01), and 17q (54.5% versus 20.0%, P = 0.03). Significant differences in AI frequency between type 1 and type 2 PRCCs were noted on 17q (78.6% versus 12.5%, P = 0.006) and 9p (0% versus 37.5%, P = 0.02). Additional analyses suggested that the relationship between 17q AI and PRCC type may be independent of histological grade and stage. Our findings identify genetic differences between the recently proposed type 1 and type 2 PRCCs, and support the premise that these subtypes arise from distinct genetic pathways.

Also flagged:polyglutaminedeathHuntington's diseaseHDpathogenesisdoxycycline
Journal Article 2002-09-01 No Snippets Kita H, Carmichael J, Swartz J, Muro S, Wyttenbach A, Matsubara K, Rubinsztein DC, Kato K.
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The majority of triplet-repeat diseases are caused by mutated genes with an extended polyglutamine tract, exemplified by Huntington's disease (HD). In order to model HD pathogenesis in a controlled system, we developed stable PC12 cell lines that express exon 1 fragments of the huntingtin gene with 23 or 74 polyglutamines driven by an inducible doxycycline (dox)-sensitive promoter (HD-23Q or HD-74Q). We aimed to identify early perturbations induced by the mutation by studying expression levels of 1824 genes at 0, 5, 10 and 18 hours after induction, using adaptor-tagged competitive PCR (ATAC-PCR). At these time points, the cells show no appreciable death or mitochondrial impairment and very low inclusion levels. A total of 126 genes, including 69 known genes, exhibited statistically significant alterations in the HD-74Q cell lines but no changes in the HD-23Q lines. We tested 11 of these genes for their abilities to modulate polyglutamine-induced cell death in transiently transfected cell models. Five genes [glucose transporter 1 (Glut1), phosphofructokinase muscle isozyme (Pfkm), prostate glutathione-S -transferase 2 (Gstm2), RNA-binding motif protein 3 (Rbm3) and KRAB-A interacting protein 1 (Krip-1)] significantly suppressed cell death in both neuronal precursor and non-neuronal cell lines, suggesting that these transcriptional changes were relevant to polyglutamine pathology. The efficient recovery of functionally relevant genes supports the utility of gene expression profiling for discovering pathways related to pathogenesis, and the importance of analyzing molecular events in the early stages of disease.

Also flagged:Major psychiatric disordersserotonin transporterSLC6A4pathogenesispsychiatric disordersbipolar disorder type I
Journal Article 2002-09-01 ✓ 2 Snippets Dimitrova A, Georgieva L, Nikolov I, Poriazova N, Krastev S, Toncheva D, Owen MJ, Kirov G.
In-Text Gene Mentions

…The serotonin transporter (5-HTT) is a suitable…

…polymorphism in the5-HTTgene does not…

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The serotonin transporter (5-HTT) is a suitable candidate gene to test for involvement in the pathogenesis of major psychiatric disorders. We used the method of family-based controls to test for association between disease and a variable number tandem repeat (VNTR) in intron 2 of the gene, which has received support for involvement in the pathogenesis of several psychiatric disorders. We analysed 413 proband-parent trios of Bulgarian origin: 266 had a schizophrenic proband, 103 had a bipolar proband and 44 had a schizoaffective proband. The results were analysed using the extended transmission disequilibrium test. Possible effects of different alleles on certain clinical variables were examined by correlation analysis. Three alleles were detected: STin2.9, STin2.10 and STin2.12. None of the three diagnostic samples showed preferential transmission of alleles that reached conventional levels of statistical significance. We could not confirm previous results that STin2.12 allele increases susceptibility to bipolar disorder type I. The rare STin2.9 showed a non-significant trend for preferential transmission in the sample as a whole: 18 transmitted versus 11 non-transmitted (P = 0.2). The VNTR polymorphism in the 5-HTT gene does not appear to be a major risk factor for increasing susceptibility to major psychiatric disorders.

Also flagged:CaspaseHuntington's diseaseHDantibodiesamino acidpolyglutamine
Journal Article 2002-09-01 ✓ 5 Snippets Wellington CL, Ellerby LM, Gutekunst CA, Rogers D, Warby S, Graham RK, Loubser O, van Raamsdonk J, Singaraja R, Yang YZ, Gafni J, Bredesen D, Hersch SM, Leavitt BR, Roy S, Nicholson DW, Hayden MR.
In-Text Gene Mentions

Caspase cleavage of mutant huntingtin precedes neurodegeneration in Huntington's disease.

Furthermore, htt fragments were detected most abundantly in cortical projection neurons, suggesting that accumulation of expanded htt fragments in these neurons may lead to corticostriatal dysfunction as an early event in the pathogenesis of HD.

Cleaved htt is also seen in wild-type and HD transgenic mouse brains before the onset of neurodegeneration.

Huntington's disease (HD) results from polyglutamine expansion in huntingtin (htt), a protein with several consensus caspase cleavage sites.

However, in HD, cleavage of mutant htt would release N-terminal fragments with the potential for increased toxicity and accumulation caused by the presence of the expanded polyglutamine tract.

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Huntington's disease (HD) results from polyglutamine expansion in huntingtin (htt), a protein with several consensus caspase cleavage sites. Despite the identification of htt fragments in the brain, it has not been shown conclusively that htt is cleaved by caspases in vivo. Furthermore, no study has addressed when htt cleavage occurs with respect to the onset of neurodegeneration. Using antibodies that detect only caspase-cleaved htt, we demonstrate that htt is cleaved in vivo specifically at the caspase consensus site at amino acid 552. We detect caspase-cleaved htt in control human brain as well as in HD brains with early grade neuropathology, including one homozygote. Cleaved htt is also seen in wild-type and HD transgenic mouse brains before the onset of neurodegeneration. These results suggest that caspase cleavage of htt may be a normal physiological event. However, in HD, cleavage of mutant htt would release N-terminal fragments with the potential for increased toxicity and accumulation caused by the presence of the expanded polyglutamine tract. Furthermore, htt fragments were detected most abundantly in cortical projection neurons, suggesting that accumulation of expanded htt fragments in these neurons may lead to corticostriatal dysfunction as an early event in the pathogenesis of HD.

Also flagged:cyclin-dependent kinase 5p35p39Cdk5neuronal migrationsynaptogenesis
Journal Article 2002-09-01 ✓ 1 Snippet Dhavan R, Greer PL, Morabito MA, Orlando LR, Tsai LH.
In-Text Gene Mentions

Densin-180

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Cyclin-dependent kinase 5 (Cdk5) is a critical regulator of neuronal migration in the developing CNS, and recent studies have revealed a role for Cdk5 in synaptogenesis and regulation of synaptic transmission. Deregulation of Cdk5 has been linked to the pathology of neurodegenerative diseases such as Alzheimer's disease. Activation of Cdk5 requires its association with a regulatory subunit, and two Cdk5 activators, p35 and p39, have been identified. To gain further insight into the functions of Cdk5, we identified proteins that interact with p39 in a yeast two-hybrid screen. In this study we report that alpha-actinin-1 and the alpha-subunit of Ca2+/calmodulin-dependent protein kinase II (CaMKIIalpha), two proteins localized at the postsynaptic density, interact with Cdk5 via their association with p35 and p39. CaMKIIalpha and alpha-actinin-1 bind to distinct regions of p35 and p39 and also can interact with each other. The association of CaMKIIalpha and alpha-actinin-1 to the Cdk5 activators, as well as to each other, is stimulated by calcium. Further, the activation of glutamate receptors increases the association of p35 and p39 with CaMKIIalpha, and the inhibition of CaMKII activation diminishes this effect. The glutamate-mediated increase in association of p35 and CaMKIIalpha is mediated in large part by NMDA receptors, suggesting that cross talk between the Cdk5 and CaMKII signal transduction pathways may be a component of the complex molecular mechanisms contributing to synaptic plasticity, memory, and learning.

Also flagged:tyrosinecytoplasmicneuronal migration disorderlissencephalyphosphotyrosineL1 cell adhesion molecule
Journal Article 2002-09-01 ✓ 1 Snippet Kizhatil K, Wu YX, Sen A, Bennett V.
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DCC

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Doublecortin is a cytoplasmic protein mutated in the neuronal migration disorder X-linked lissencephaly. This study describes a novel activity of doublecortin in recognition of the FIGQY-phosphotyrosine motif present in the cytoplasmic domain of the L1 cell adhesion molecule neurofascin. Phospho-FIGQY-neurofascin (186 kDa) coimmunoprecipitated with doublecortin from detergent extracts of embryonic brain membranes, and this doublecortin-phospho-FIGQY neurofascin complex was disassociated by a synthetic phospho-FIGQY neurofascin peptide but not by a dephospho-FIGQY peptide. Doublecortin specifically recognized the phospho-FIGQY tyrosine in the context of a synthetic phospho-FIGQY neurofascin peptide and in phospho-FIGQY neurofascin isolated from cells treated with pervanadate. Mutations of doublecortin causing lissencephaly (R59H, D62N, and G253D) abolished binding to the phospho-FIGQY peptide and to phospho-FIGQY neurofascin. Finally, phospho-FIGQY neurofascin and doublecortin colocalize in developing axon tracts and in zones enriched in migrating neurons in the embryonic cerebral cortex. In the adult rostral migratory stream, doublecortin colocalizes in migrating neurons with a phospho-FIGQY bearing L1 CAM different from neurofascin. The finding that doublecortin associates with FIGQY-phosphorylated neurofascin provides the first connection of doublecortin with the plasma membrane and could be important for a function of doublecortin in directing neuronal migration.

Also flagged:Metalloproteasesgrowth conesgrowth conemetalloproteaseaxonsaxon
Journal Article 2002-09-01 ✓ 2 Snippets Webber CA, Hocking JC, Yong VW, Stange CL, McFarlane S.
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DCC

DCC receptors

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Axonal growth cones read cues in their environment that guide them to their target. Metalloproteases have been implicated in vitro in modulating the interaction of these cues with receptors in the growth cone. To determine whether metalloprotease function is important in the guidance of vertebrate axons in vivo, we applied hydroxamate-based metalloprotease inhibitors to Xenopus retinal ganglion cell (RGC) axons as they extended through the optic tract. In the presence of two different inhibitors, 0.5-20 microm N-[(2R)-2(hydroxamideocarbonylmethyl)-4-methylpantanoyl]-l-tryptophan methylamide and batimastat, RGC axons made similar dose-dependent guidance errors. Most axons failed to make the expected caudal turn in the diencephalon and continued straight, growing aberrantly toward and across the dorsal midline. As a result, few RGC axons innervated their midbrain target, the optic tectum. Similarly, if the inhibitors were applied after the axons made the turn, many failed to grow into the optic tectum and instead turned to grow along its anterior border. Interestingly, in many instances pathfinding defects were observed in the absence of problems with axon extension, although outgrowth was impaired at the higher doses of the inhibitors. These data provide compelling in vivo evidence that metalloproteases are important for both axon guidance and extension in the developing visual system.

Also flagged:Huntington's diseaseHDlocomotionenkephalinHuntingtinparaformaldehyde
Journal Article 2002-09-01 No Snippets Menalled LB, Sison JD, Wu Y, Olivieri M, Li XJ, Li H, Zeitlin S, Chesselet MF.
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Huntington's disease (HD) is characterized by a progressive loss of neurons in the striatum and cerebral cortex and is caused by a CAG repeat expansion in the gene encoding huntingtin. Mice with the mutation inserted into their own huntingtin gene (knock-in mice) are, genetically, the best models of the human disease. Here we show for the first time that knock-in mice with 94 CAG repeats develop a robust and early motor phenotype at 2 months of age, characterized by increased rearing at night. This initial increase in repetitive movements was followed by decreased locomotion at 4 and 6 months, despite a normal life span. The decrease in striatal enkephalin mRNA that is known to occur at 4 months was not present at 2 months, when increased rearing was observed. Both the hyperactive and hypoactive phases of motor dysfunction preceded the detection of nuclear microaggregates of mutated huntingtin in striatal neurons. Nuclear microaggregates, defined as small huntingtin-positive punctas detected by light microscopy, were very rare at 4 months but became widely distributed in striatal neurons at 6 months. Nuclear inclusions did not appear until 18 months. When present, nuclear microaggregates predominated in the striosomal compartment of the striatum, providing a possible explanation for the different neuronal vulnerability of striatal compartments observed in humans. The early motor phenotype observed in the knock-in mouse is reminiscent of repetitive movements often observed in early HD and provides a novel opportunity to assess the ability of therapies to prevent the initial effects of the mutation in vivo.

Also flagged:nitric oxide synthaseHuntington's diseaseHDneurodegenerative disorderpolyglutamineNitric oxide
Journal Article 2002-09-01 ✓ 3 Snippets Pérez-Severiano F, Escalante B, Vergara P, Ríos C, Segovia J.
In-Text Gene Mentions

Huntington's disease (HD) is an autosomal hereditary neurodegenerative disorder caused by an abnormal expansion of the CAG repeats that code for a polyglutamine tract in a novel protein called huntingtin (htt).

…protein called huntingtin (htt).…

…a human mutatedhttexon 1 with…

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Huntington's disease (HD) is an autosomal hereditary neurodegenerative disorder caused by an abnormal expansion of the CAG repeats that code for a polyglutamine tract in a novel protein called huntingtin (htt). Both patients and experimental animals exhibit oxidative damage in specific areas of the brain, particularly the striatum. Nitric oxide (NO) is involved in many different physiological processes, and under pathological conditions it may promote oxidative damage through the formation of the highly reactive metabolite peroxynitrite; however, it may also play a role protecting cells from oxidative damage. We previously showed a correlation between the progression of the neurological phenotype and striatal oxidative damage in a line of transgenic mice, R6/1, which expresses a human mutated htt exon 1 with 116 CAG repeats. The purpose of the present work was to explore the participation of NO in the progressive oxidative damage that occurs in the striata of R6/1 mice. We analyzed the role of NO by measuring the activity of nitric oxide synthase (NOS) in the striata of transgenic and control mice at different ages. There was no difference in NOS activity between transgenic and wild-type mice at 11 weeks of age. In contrast, 19-week-old transgenic mice showed a significant increase in NOS activity, compared with same age controls. By 35 weeks of age, there was a decrease in NOS activity in transgenic mice when compared with wild-type controls. NOS protein expression was also determined in 11-, 19- and 35-week-old transgenic mice and wild-type littermates. Our results show increased neuronal NOS expression in 19-week-old transgenic mice, followed by a decreased level in 35-week-old mice, compared with controls, a phenomenon that parallels the changes in NOS enzyme activity. The present results suggest that NO is involved in the process leading to striatal oxidative damage and that it is associated with the onset of the progressive neurological phenotype in mice transgenic for the HD mutation.

Also flagged:CD30viral infectionssmallpoxCD30Linflammatory responsesType 1 Cytokine
Journal Article 2002-09-01 ✓ 2 Snippets Saraiva M, Smith P, Fallon PG, Alcami A.
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…of mice withtype 1 granulomas1 granulomas caused…

…the spleens oftype 1 granuloma1 granuloma–sensitized mice…

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CD30 is up-regulated in several human diseases and viral infections but its role in immune regulation is poorly understood. Here, we report the expression of a functional soluble CD30 homologue, viral CD30 (vCD30), encoded by ectromelia (mousepox) virus, a poxvirus that causes a severe disease related to human smallpox. We show that vCD30 is a 12-kD secreted protein that not only binds CD30L with high affinity and prevents its interaction with CD30, but it also induces reverse signaling in cells expressing CD30L. vCD30 blocked the generation of interferon gamma-producing cells in vitro and was a potent inhibitor of T helper cell (Th)1- but not Th2-mediated inflammation in vivo. The finding of a CD30 homologue encoded by ectromelia virus suggests a role for CD30 in antiviral defense. Characterization of the immunological properties of vCD30 has uncovered a role of CD30-CD30L interactions in the generation of inflammatory responses.

Also flagged:inflammatory responseultrafiltrationmethylprednisoloneCytokinesTNFalphaIL-6
Journal Article 2002-09-01 ✓ 1 Snippet Chew MS, Brix-Christensen V, Ravn HB, Brandslund I, Ditlevsen E, Pedersen J, Hjortholm K, Hansen OK, Tønnesen E, Hjortdal VE.
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…(F1 + 2,ATIII) were measured pre-,…

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Modified ultrafiltration (MUF) is often used in conjunction with paediatric cardiac surgery with cardiopulmonary bypass (CPB) and is thought to improve clinical outcome. It is unclear whether these improvements (if any) are due to the removal of inflammatory mediators. In this prospective study, 18 children aged 12-24 months undergoing uncomplicated cardiac surgery with methylprednisolone added in the pump prime were randomized to receive CPB with (n = 10) and without (n = 8) MUF. Cytokines (TNFalpha, IL-6, IL-1beta, IL-10, IL-1ra), complement split products (C3d, C4d) and coagulation system activation (F1 + 2, ATIII) were measured pre-, peri- and up to 48 h postoperatively. For clinical outcome, the alveolar-arterial oxygen (A-a) gradient, transfusion requirement, drain loss, mean blood pressure and requirement for inotropic support were registered up to 24 h postoperatively. Our results show an improvement in postoperative oxygenation as well as a tendency towards decreased drain loss and improved haemodynamics in the MUF group. There were no intergroup differences detectable for TNFalpha, IL-1beta, IL-1ra, complement and coagulation markers. We conclude that MUF in itself does not significantly influence TNFalpha, IL-1beta, IL-1ra and the complement and coagulation profiles in children undergoing cardiac surgery with CPB. Despite this, there was some evidence for improved clinical outcome. Our results do not support that MUF improves postoperative organ function by modulation of the measured markers of inflammation.

Also flagged:hepatic veno-occlusive diseaseacute lymphoblastic leukemiaALLheparinprostaglandin E1ursodeoxycholic acid
Journal Article 2002-09-01 ✓ 1 Snippet Kim ID, Egawa H, Marui Y, Kaihara S, Haga H, Lin YW, Kudoh K, Kiuchi T, Uemoto S, Tanaka K.
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…neither defibrotide norantithrombin-IIIimproved the hepatic…

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An 11-month-old boy with acute lymphoblastic leukemia (ALL) underwent umbilical cord blood transplantation (CBT) from an unrelated donor after a first complete remission. Despite the prophylactic use of low molecular weight heparin, prostaglandin E1 and ursodeoxycholic acid, hepatic veno-occlusive disease (VOD) occurred on the 29th day after CBT. Furthermore, neither defibrotide nor antithrombin-III improved the hepatic coma and coagulopathy due to the hepatic VOD. On the 42nd day after CBT, he underwent living related liver transplantation (LRLT) with a left lateral segment graft from his father. He received tacrolimus for the prevention of rejection and graft-vs.-host disease (GVHD) and also received aggressive antifungal and antiviral prophylaxis. Although he showed signs of acute rejection on postoperative days 5 and 10, the postoperative course was uneventful in general. At present, 17 months after LRLT, the patient shows stable liver function and no signs of either GVHD or a relapse of ALL. In conclusion, LRLT can be seen as a feasible option for the treatment of a hepatic VOD after CBT, though aggressive prophylaxis for infection and the anticipation of acute rejection are of importance.

Also flagged:tryptophan hydroxylase5-HT1A receptorbindingHuntington's diseaseHDserotonin
Journal Article 2002-09-01 ✓ 1 Snippet Yohrling IV GJ, Jiang GC, DeJohn MM, Robertson DJ, Vrana KE, Cha JH.
In-Text Gene Mentions

The pathogenic mechanisms of the mutant huntingtin protein that cause Huntington's disease (HD) are unknown.

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The pathogenic mechanisms of the mutant huntingtin protein that cause Huntington's disease (HD) are unknown. Previous studies have reported significant decreases in the levels of serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the brains of the R6/2 transgenic mouse model of HD. In an attempt to elucidate the cause of these neurochemical perturbations in HD, the protein levels and enzymatic activity of tryptophan hydroxylase (TPH), the rate-limiting enzyme in 5-HT biosynthesis, were determined. Enzyme activity was measured in brainstem homogenates from 4-, 8-, and 12-week-old R6/2 mice and compared with aged-matched wild-type control mice. We observed a 62% decrease in brainstem TPH activity (p = 0.009) in 4-week-old R6/2 mice, well before the onset of behavioral symptoms. In addition, significant decreases in TPH activity were also observed at 8 and 12 weeks of age (61%, p = 0.02 and 86%, p = 0.005, respectively). In the 12-week-old-mice, no change in immunoreactive TPH was observed. In vitro binding showed that TPH does not bind to exon 1 of huntingtin in a polyglutamine-dependent manner. Specifically, glutathione-S-transferase huntingtin exon 1 proteins with 20, 32 or 53 polyglutamines did not interact with radiolabeled tryptophan hydroxylase. Therefore, the inhibition of TPH activity does not appear to result from a direct huntingtin/TPH interaction. Receptor binding analyses for the 5-HT1A receptor in 12-week-old R6/2 mice revealed significant reductions in 8-OH-[3H]DPAT binding in several hippocampal and cortical regions. These results demonstrate that the serotonergic system in the R6/2 mice is severely disrupted in both presymptomatic and symptomatic mice. The presymptomatic inhibition of TPH activity in the R6/2 mice may help explain the functional consequences of HD and provide insights into new targets for pharmacotherapy.

Also flagged:estrogen receptorprogesterone receptordextranbreast cancersERestradiol
Journal Article 2002-09-01 ✓ 5 Snippets Morimoto K, Hasuma T, Koh M, Ohtani S, Kinoshita H.
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breast cancers were studied to investigate the consistency and correlations between dextran charcoal assay (DCC) and enzyme immunoassay (EIA) for estrogen receptor

breast cancers were studied to investigate the consistency and correlations between dextran charcoal assay (DCC) and enzyme immunoassay (EIA) for estrogen receptor (ER) and progesterone receptor

…for consistency ofDCCand EIA, for…

…patients for bothDCCand EIA.…

…found for bothDCCand EIA.…

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Six hundred and eighty-eight breast specimens including 442 breast cancers were studied to investigate the consistency and correlations between dextran charcoal assay (DCC) and enzyme immunoassay (EIA) for estrogen receptor (ER) and progesterone receptor (PgR). In DCC, ER was quantitated with competition of 16 alpha-125I-estradiol and diethyl stilbesterol, and PgR with 3H-R5020 and R5020. In EIA, kit from Abbott was used in ER and PgR quantitation. The mean age of the patients was 52 years and the mean age of patients with benign lesions was 39 years. The consistency rate was 95% for ER, and 83% for PgR, while the consistency coefficient kappa was 0.90 and 0.66, respectively. For the specimens in which the number of binding sites was calculated in both DCC (x) and EIA (y), the correlation coefficient was 0.787 and the linear regression formula was y = 0.5x + 58. For PgR, the correlation coefficient kappa was 0.612 and the regression formula was y = 2.6x + 91. In multiple regression analysis for consistency of DCC and EIA, for ER, there was an inconsistent trend for positive PgR and a consistent trend for patients in their fifties. For PgR, the trend was inconsistent for benign lesions and positive ER. In comparison with the efficacy of endocrine treatment, no responder was found in ER negative patients for both DCC and EIA. In PgR-negative patients a responder was found for both DCC and EIA. By Western blot analysis, anti-ER antibody provided in the ER.EIA kit showed affinity only for ER alpha and not for beta. In conclusion, in terms of the treatment efficacy for both ER and PgR, the current use of ER with EIA instead of DCC seems to give equivalent result, and old DCC data can be converted into the regression formula. However, PgR calculated by EIA was not equivalent with that of DCC.

Also flagged:Phosphorylationlinker histone H1chromatinGFPH1binding
Journal Article 2002-09-01 ✓ 3 Snippets Dou Y, Bowen J, Liu Y, Gorovsky MA.
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…effects ascribed tolinker histoneshistones were based…

…is that thelinker histoneshistones of unicellular…

…COOH-terminal tail) oflinker histoneshistones in multicellular…

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In Tetrahymena cells, phosphorylation of linker histone H1 regulates transcription of specific genes. Phosphorylation acts by creating a localized negative charge patch and phenocopies the loss of H1 from chromatin, suggesting that it affects transcription by regulating the dissociation of H1 from chromatin. To test this hypothesis, we used FRAP of GFP-tagged H1 to analyze the effects of mutations that either eliminate or mimic phosphorylation on the binding of H1 to chromatin both in vivo and in vitro. We demonstrate that phosphorylation can increase the rate of dissociation of H1 from chromatin, providing a mechanism by which it can affect H1 function in vivo. We also demonstrate a previously undescribed ATP-dependent process that has a global effect on the dynamic binding of linker histone to chromatin.

Also flagged:Hereditary haemochromatosisironhaemochromatosis
Journal Article 2002-09-01 ✓ 4 Snippets Larsen LE, Ellervik C, Appleyard M, Nordestgaard BG, Birgens H, Tybjaerg-Hansen A.
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In Northern Europe, 85-90% of patients with haemochromatosis are homozygous for the C282Y mutation in the HFE gene.

…[Prevalence ofhemochromatosis-associated mutations in the…

…mutations in thehemochromatosisgene in the…

…mutation in theHFEgene.…

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<h4>Introduction</h4>Hereditary haemochromatosis is an autosomal recessive condition characterised by systemic iron overload. In Northern Europe, 85-90% of patients with haemochromatosis are homozygous for the C282Y mutation in the HFE gene. In the present study, we determined the prevalence of the haemochromatosis-associated mutations, C282Y and H63D, in the Danish general population.<h4>Material and methods</h4>We genotyped 9174 individuals from a random sample of the Danish general population (The Copenhagen City Heart Study), stratified by gender and age in 10-year age groups, for the presence of C282Y and H63D.<h4>Results</h4>In The Copenhagen City Heart Study, 0.25% (95% confidence interval: 0.16-0.38%) were homozygous for C282Y, 1.4% (1.2-1.7%) were compound heterozygous for C282Y/H63D, and 9.2% (8.6-9.9%) were heterozygous for C282Y alone. Accordingly, the allele frequencies of C282Y and H63D in the Danish population were 5.6% (5.3-5.9%) and 12.7% (12.2-13.2%). All in all, more than 10% of the Danish population are either homozygous or heterozygous for C282Y, whereas about 24% are either homozygous or heterozygous for H63D.<h4>Conclusion</h4>A prevalence of 0.25% homozygotes and > 10% heterozygotes for C282Y makes hereditary haemochromatosis the potentially most common inherited disorder in Denmark. However, in new studies from USA of the association between genotype and disease in unselected populations the penetrance is very low. On this background, population screening for the presence of these mutations is not advisable.

Also flagged:Sox5L-SOX5SoxSry-type HMG boxtranscription factorsbinding
Journal Article 2002-09-01 ✓ 5 Snippets Ikeda T, Zhang J, Chano T, Mabuchi A, Fukuda A, Kawaguchi H, Nakamura K, Ikegawa S.
In-Text Gene Mentions

The predicted L-SOX5 protein shares 97% amino acid identity with its mouse counterpart and 59% identity with human SOX6.

Sox5 and Sox6 belong to the group D subfamily, which is characterized by conserved N-terminal domains including a leucine-zipper, a coiled-coil domain and a Q-box.

…Sox5 andSox6belong to the…

…and interacts withSox6; together, these two…

…identity with humanSOX6.…

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The Sox (Sry-type HMG box) group of transcription factors, which is defined by a high-mobility group (HMG) DNA-binding domain, is categorized into six subfamilies. Sox5 and Sox6 belong to the group D subfamily, which is characterized by conserved N-terminal domains including a leucine-zipper, a coiled-coil domain and a Q-box. Group D Sox genes are expressed as long and short transcripts that exhibit differential expression patterns. In mouse, the long form of Sox5, L-Sox5, is co-expressed and interacts with Sox6; together, these two proteins appear to play a key role in chondrogenesis and myogenesis. In humans, however, only the short form of Sox5 has previously been identified. To gain insight into Sox5 function, we have identified and characterized human L-SOX5. The human L-SOX5 cDNA encodes a 763-amino-acid protein that is 416 residues longer than the short form and contains all of the characteristic motifs of group D Sox proteins. The predicted L-SOX5 protein shares 97% amino acid identity with its mouse counterpart and 59% identity with human SOX6. The L-SOX5 gene contains 18 exons and shows similar genomic structure to SOX6. We have identified two transcription start sites in L-SOX5 and multiple alternatively spliced mRNA variants that are distinct from the short form. Unlike the short form, which shows testis-specific expression, L-SOX5 is expressed in multiple tissues. Like SOX6, L-SOX5 shows strong expression in chondrocytes and striated muscles, indicating a likely role in human cartilage and muscle development.

Also flagged:copperelectron transferoxygenbindingCeruloplasminmulticopper oxidase
Journal Article 2002-09-01 No Snippets Bielli P, Calabrese L.
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Specialised copper sites have been recruited during evolution to provide long-range electron transfer reactivity and oxygen binding and activation in proteins destined to cope with oxygen reactivity in different organisms. Ceruloplasmin is an ancient multicopper dase evolved to insure a safe handling of oxygen in some metabolic pathways of vertebrates. The presently available knowledge of its structure provides a glimpse of its plasticity, revealing a multitude of binding sites that point to an elaborate mechanism of multifunctional activity. Ceruloplasmin represents an example of a 'moonlighting' protein that overcomes the one gene-one structure-one function concept to follow the changes of the organism in its physiological and pathological conditions.

Also flagged:Huntington's diseaseHDdementiacharacteropathypolymerasepolyacrylamide
Journal Article 2002-09-01 No Snippets Zielonka D, de Mezer M, Niezgoda A, Reperowicz K, Krzyzosiak W, Kozubski W.
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Huntington's disease (HD) is a neurological condition of progressive course that results from abnormally increased number of CAG repeats within IT-15 gene, coding for huntington. The main symptoms consist of choraetic movements, dementia, and characteropathy. The aim of the present study was to search for possible correlation between the age of the onset of HD, time from the onset, clinical status of the patients, and CAG repeats number. Ten patients were studied altogether. Modified UHDRS (MUHDRS) was applied for the estimation of patients' clinical status. The number of CAG repeats in examination of the IT-15 gene was determined by polymerase chain reaction (PCR) and separation of radioisotope labelled PCR product against DNA size marker in polyacrylamide gel. A negative significant correlation was found between the CAG repeats number and the disease onset age (r = -0.67; p < 0.05) and MUHDRS score (r = 0.75; p < 0.05), as well. Negative significant correlation between time from the onset and MUHDRS score (r = -0.95; p < 0.05) and negative correlation between summarised: time from the onset and CAG number on the one site and MUHDRS on the other (p = -0.91) were found, as well. Our findings indicate an interdependence between CAG repeats number within the IT-15 gene, the course of the disease and the clinical status of HD patients.

Also flagged:Anxietybehavioralpeptidesmood disordersadenocorticotropic hormonenucleus
Journal Article 2002-09-01 ✓ 1 Snippet Steimer T.
In-Text Gene Mentions

In contrast, 5-HT1B receptor knockout mice were found to be more aggressive, more reactive, and less anxious than their wild-type counterparts, suggesting that this receptor may also modulate 5-HT action on defense mechanisms.93 Serotonin transporter (5-HTT) knockout mice (5-HTT-/-) have also been produced, and shown to display elevated anxiety in various behavioral tests, and an increased stress response (adenocorticotropic hormone [ACTH] secretion) following a mild stress, which was also observed to a lesser degree in the 5-HTT+/- heterozygotes.94

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Anxiety is a psychological, physiological, and behavioral state induced in animals and humans by a threat to well-being or survival, either actual or potential. It is characterized by increased arousal, expectancy, autonomic and neuroendocrine activation, and specific behavior patterns. The function of these changes is to facilitate coping with an adverse or unexpected situation. Pathological anxiety interferes with the ability to cope successfully with life challenges. Vulnerability to psychopathology appears to be a consequence of predisposing factors (or traits), which result from numerous gene-environment interactions during development (particularly during the perinatal period) and experience (life events), in this review, the biology of fear and anxiety will be examined from systemic (brain-behavior relationships, neuronal circuitry, and functional neuroanatomy) and cellular/molecular (neurotransmitters, hormones, and other biochemical factors) points of view, with particular reference to animal models. These models have been instrumental in establishing the biological correlates of fear and anxiety, although the recent development of noninvasive investigation methods in humans, such as the various neuroimaging techniques, certainly opens new avenues of research in this field. Our current knowledge of the biological bases of fear and anxiety is already impressive, and further progress toward models or theories integrating contributions from the medical, biological, and psychological sciences can be expected.

Are there anxious genes?

Also flagged:Anxietypsychiatric disordersserotonin (5-hydroxytryptamine, 5-HT) transportergene expressionpanic disorderPD
Journal Article 2002-09-01 ✓ 5 Snippets Morris-Rosendahl DJ.
In-Text Gene Mentions

These results were very recently extended and confirmed by the same group in an independent group of bipolar disorder families.15 In the same recent issue of the American Journal of Psychiatry, Rotondo and colleagues16 conducted a casecontrol association study of the genetic polymorphisms of three monoamine neurotransmitter system candidate genes, catechol-O-methyltransferase (COMT), serotonin (5-hydroxytryptamine or 5-HT) transporter (5-HTT), and tryptophan hydroxylase (TPH), in patients with bipolar disorder with and without lifetime PD.

Extensive genetic studies of the 5-HTT gene have revealed how variation in gene expression can be correlated with anxiety phenotypes.

Mood, anxiety, emotion, and cognition are modulated by the serotonergic midbrain raphe system, and a dysregulation of 5-HTT expression might be important in the course of these disorders.28 Transporter-facilitated uptake of 5-HT has been implicated in anxiety in human and animal models and is the site of action of widely used uptakeinhibiting antidepressant and antianxiety drugs.

Extensive genetic studies of the serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) gene have revealed how variation in gene expression can be correlated with anxiety phenotypes.

…ryptamine, 5-HT) transporter (5-HTT) gene have revealed…

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Anxiety comprises many clinical descriptions and phenotypes. A genetic predisposition to anxiety is undoubted; however, the nature and extent of that contribution is still unclear. Methods for the genetic analysis of such complex disorders is briefly reviewed, followed by a discussion of the comorbidity of anxiety with other psychiatric disorders and their possible common genetic etiology. Extensive genetic studies of the serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) gene have revealed how variation in gene expression can be correlated with anxiety phenotypes. Complete genome-wide linkage scans for panic disorder (PD) susceptibility genes have suggested a locus on chromosome arm 7p, and association studies have highlighted many candidate genes. A highly significant association between phobias, panic disorder, and a duplication at chromosomal region 15q24-26 is one of the most exciting findings to date. Emerging molecular genetic technologies and the use of increasingly sophisticated animal models of anxiety provide great promise for the future of the field.