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PubMed2026

MicroRNA-181a-5p promotes papillary thyroid carcinoma progress via the PTEN/AKT pathway.

The objective of this investigation was to determine the expression profile and latent mechanism of microRNA-181a-5p (miR-181a-5p) in the genesis and progression of papillary thyroid cancer (PTC). MiR-181a-5p was discovered to be upregulated in PTC tissues and cells in this study, as confirmed by RT‒qPCR and The Cancer Genome Atlas database. Notably, in PTC patients, the miR-181a-5p level was linked to tumor size and thyroid capsule invasion. A series of experiments demonstrated that miR-181a-5p upregulation in PTC cells notably enhanced proliferation, motility, and invasion, whereas suppressing miR-181a-5p hindered these functions. Western blotting revealed that miR-181a-5p suppressed PTEN expression, boosting the activation of phosphorylated AKT (P-AKT). According to predictive bioinformatics research and luciferase reporter gene tests, miR-181a-5p may target a specific binding site on the PTEN 3'UTR. To sum up, this study indicated that miR-181a-5p promoted PTC progression through the PTEN/Akt pathway. This investigation reveals a potential mechanism for PTC progression and provides a foundation for clinical therapies.

MicroRNAs↗
PubMed2026

Integrative analysis of the roles and prognostic value of RNA-binding proteins in papillary renal cell carcinoma.

RNA-binding proteins (RBPs) serve essential roles in various cancer types, but their functions in papillary renal cell carcinoma (pRCC) have not been elucidated to date. In our work, differentially expressed RBPs in pRCC were identified after acquisition of RNA-sequencing and clinical data related to pRCC from The Cancer Genome Atlas database(TCGA). Functional enrichment analysis and protein interaction network analysis, along with univariate and multivariate Cox regression analyses, were performed to uncover potential biological effects of the identified RBPs and screen the hub RBPs for pRCC prognosis. We identified 251 up-regulated and 129 down-regulated RBPs, and filtered out seven hub RBPs, namely, SRSF8, CD3EAP, HBS1L, ELAC2, MRPL34, NOP2 and IGF2BP2, for their prognostic relevance. A prognostic risk score model for overall survival of pRCC patients was constructed based on the seven hub RBPs. Further analysis showed that the low-risk group had higher survival rate than the high-risk group in both training and validation cohorts. The predictive accuracy was verified in the Human Protein Atlas database.In addition, we introduced the GSE15641 dataset from the Gene Expression Omnibus (GEO) database for independent external validation, and confirmed the expression levels of HBS1L, MRPL34 and IGF2BP2 through real-time quantitative PCR (RT-qPCR) and Western blotting (WB) using human renal tubular epithelial cell line HK-2 and human papillary renal cell carcinoma cell line Caki-2. In pRCC, CD3EAP was significantly elevated, while ELAC2, IGF2BP2, MRPL34, SRSF8 and HBS1L were significantly reduced. There was no significant difference between tumor and normal tissues in NOP2 expression. Risk score and tumor grade were independent prognostic factors associated with overall survival. In addition, we established a nomogram based on the seven prognostic RBPs to help predict overall survival at 1-3 years. In conclusion, seven differentially expressed hub RBPs were identified as potential prognostic biomarkers for pRCC. Our prognostic model might serve as a support for better treatment decision-making. Our work could provide potential new ideas for diagnosis and research on targeted drugs for pRCC.

Bioinformatics↗
PubMed2006

Knockdown of nuclear Ca2+/calmodulin-dependent protein kinase phosphatase causes developmental abnormalities in zebrafish.

Nuclear Ca2+/calmodulin-dependent protein kinase phosphatase (CaMKP-N) is an enzyme that dephosphorylates and concomitantly downregulates multifunctional Ca2+/calmodulin-dependent protein kinases (CaMKs) in vitro. However, the functional roles of this enzyme in vivo are not well understood. To investigate the biological significance of CaMKP-N during zebrafish embryogenesis, we cloned and characterized zebrafish CaMKP-N (zCaMKP-N). Based on the nucleotide sequences in the zebrafish whole genome shotgun database, we isolated a cDNA clone for zCaMKP-N, which encoded a protein of 633 amino acid residues. Transiently expressed full-length zCaMKP-N in mouse neuroblastoma, Neuro2a cells, was found to be localized in the nucleus. In contrast, the C-terminal truncated mutant lacking RKKRRLDVLPLRR (residues 575-587) had cytoplasmic staining, suggesting that the nuclear localization signal of zCaMKP-N exists in the C-terminal region. Ionomycin treatment of CaMKIV-transfected Neuro2a cells resulted in a marked increase in the phosphorylated form of CaMKIV. However, cotransfection with zCaMKP-N significantly decreased phospho-CaMKIV in ionomycin-stimulated cells. Whole mount in situ hybridization analysis of zebrafish embryos showed that zCaMKP-N is exclusively expressed in the head and neural tube regions. Gene knockdown of zCaMKP-N using morpholino-based antisense oligonucleotides induced significant morphological abnormalities in zebrafish embryos. A number of apoptotic cells were observed in brain and spinal cord of the abnormal embryos. These results suggest that zCaMKP-N plays a crucial role in the early development of zebrafish.

Amino Acid Sequence↗
PubMed2004

Dictyostelium nucleomorphin is a member of the BRCT-domain family of cell cycle checkpoint proteins.

A search of the Dictyostelium genome project database (http://dictybase.org/db/cgi-bin/blast.pl) with nucleomorphin, a protein that regulates the nuclear number, predicted it to be encoded by a larger gene containing a putative breast cancer carboxy-terminus domain (BRCT). Using RT-PCR, Northern and Western blotting we have identified a differentially expressed, 2318 bp cDNA encoding a protein isoform of Dictyostelium NumA with an apparent molecular weight of 70 kDa that we have called NumB. It contains a single amino-terminal BRCT-domain spanning residues 125-201. Starvation of shaking cultures reduces NumA expression by approximately 88+/-5.6%, whereas NumB expression increases approximately 35+/-3.5% from vegetative levels. NumC, a third isoform that is also expressed during development but not growth, remains to be characterized. These findings suggest NumB may be a member of the BRCT-domain containing cell cycle checkpoint proteins.

Amino Acid Sequence↗
PubMed2006

Molecular characterization and localization of Plasmodium falciparum choline kinase.

Generation of phosphocholine by choline kinase is important for phosphatidylcholine biosynthesis via Kennedy pathway and phosphatidylcholine biosynthesis is essential for intraerythrocytic growth of malaria parasite. A putative gene (Gene ID PF14_0020) in chromosome 14, having highest sequence homology with choline kinase, has been identified by BLAST searches from P. falciparum genome sequence database. This gene has been PCR amplified, cloned, over-expressed and characterized. Choline kinase activity of the recombinant protein (PfCK) was validated as it catalyzed the formation of phosphocholine from choline in presence of ATP. The K(m) values for choline and ATP are found to be 145+/-20 microM and 2.5+/-0.3 mM, respectively. PfCK can phosphorylate choline efficiently but not ethanolamine. Southern blotting indicates that PfCK is a single copy gene and it is a cytosolic protein as evidenced by Western immunoblotting and confocal microscopy. A model structure of PfCK was constructed based on the crystal structure of choline kinase of C. elegans to search the structural homology. Consistent with the homology modeling predictions, CD analysis indicates that the alpha and beta content of PfCK are 33% and 14%, respectively. Since choline kinase plays a vital role for growth and multiplication of P. falciparum during intraerythrocytic stages, we can suggest that this well characterized PfCK may be exploited in the screening of new choline kinase inhibitors to evaluate their antimalarial activity.

Adenosine Triphosphate↗
PubMed2004

Direct evidence for cyanide-insensitive quinol oxidase (alternative oxidase) in apicomplexan parasite Cryptosporidium parvum: phylogenetic and therapeutic implications.

Cryptosporidium parvum is a parasitic protozoan that causes the diarrheal disease cryptosporidiosis, for which no satisfactory chemotherapy is currently available. Although the presence of mitochondria in this parasite has been suggested, its respiratory system is poorly understood due to difficulties in performing biochemical analyses. In order to better understand the respiratory chain of C. parvum, we surveyed its genomic DNA database in GenBank and identified a partial sequence encoding cyanide-insensitive alternative oxidase (AOX). Based on this sequence, we cloned C. parvum AOX (CpAOX) cDNA from the phylum apicomplexa for the first time. The deduced amino acid sequence (335 a.a.) of CpAOX contains diiron coordination motifs (-E-, -EXXH-) that are conserved among AOXs. Phylogenetic analysis suggested that CpAOX is a mitochondrial-type AOX, possibly derived from mitochondrial endosymbiont gene transfer. The recombinant enzyme expressed in Escherichia coli showed quinol oxidase activity. This activity was insensitive to cyanide and highly sensitive to ascofuranone, a specific inhibitor of trypanosome AOX.

Amino Acid Sequence↗
PubMed2006

Substrate specificity of Arabidopsis 3-ketoacyl-CoA synthases.

The very long chain fatty acids (VLCFA) incorporated into plant lipids are derived from the iterative addition of C2 units provided by malonyl-CoA to an acyl-CoA by the 3-ketoacyl-CoA synthase (KCS) component of a fatty acid elongase (FAE) complex. Mining of the Arabidopsis genome sequence database revealed 20 genes with homology to seed-specific FAE1 KCS. Eight of the 20 putative KCSs were cloned, expressed in yeast, and isolated as (His)6 fusion proteins. Five of the eight (At1g71160, At1g19440, At1g07720, At5g04530, and At4g34250) had little or no activity with C16 to C20 substrates while three demonstrated activity with C16, C18, and C20 saturated acyl-CoA substrates. At1g01120 KCS (KCS1) and At2g26640 KCS had broad substrate specificities when assayed with saturated and mono-unsaturated C16 to C24 acyl-CoAs while At4g34510 KCS was specific for saturated fatty acyl-CoA substrates.

3-Oxoacyl-(Acyl-Carrier-Protein) Synthase↗
PubMed2004

Using humans to study the physiological evolution of energy metabolism: a tribute to Peter Hochachka.

Comparative physiology traditionally relies on unusual animals to explore the mechanistic basis or evolution of physiological processes. Despite his credentials as a comparative physiologist, much of the recent work by Peter Hochachka relied upon humans as "comparative" models. Technological advances in clinical analyses and expanding databases of genomic diversity have made humans a very "convenient" model to study the evolution of metabolism. For example, a growing number of metabolic diseases have been shown to have a genetic basis. Obesity, type II diabetes, metabolic syndrome X may each have linkages to polymorphisms in genes encoding transcriptional regulators of bioenergetic genes. Genetic polymorphisms and gene families for these important transcription factors inspire questions about the evolution of energy metabolism in other animals. Thus, these biomedical studies provide important direction for researchers interested in exploring the regulatory basis of interspecies variations in bioenergetics.

Biological Evolution↗
PubMed2003

Molecular cloning of a putative Ciona intestinalis cionin receptor, a new member of the CCK/gastrin receptor family.

Cionin, a peptide showing similarities with cholecystokinin and gastrin has been shown to be expressed in the gut and neural ganglion of the protochordate Ciona intestinalis. The present report describes the cloning of a putative cionin receptor (CioR), a new member of the CCK/gastrin family from the gastrointestinal tract of C. intestinalis. mRNA from the stomach of C. intestinalis was isolated using a modified RNA extraction procedure and, subsequently, reverse-transcribed into single-stranded cDNA by means of rapid amplification of 5'- and 3'-cDNA ends (RACE-PCR), followed by full-length PCR amplification. The cloned full-length PCR amplicons contained a short upstream open-reading frame (uORF) coding for a putative 16 amino acid long peptide, followed by a long open reading frame encoding a 526 amino acid putative CioR protein. At the amino acid level, the putative CioR protein shared 35-40% homology with cloned mammalian, chicken, and Xenopus laevis CCK receptors. Phylogenetic analysis revealed that the chicken and X. laevis CCK receptors are orthologues of the mammalian CCK2 receptors whereas CioR protein forms a clade with vertebrate cholecystokinin receptors. Moreover, we found that the CioR cDNA and deduced amino acid sequences were found to correspond to the annotated CCK/gastrin-like receptor gene on Scaffold 117 (C. intestinalis draft genome project, Joint Genome Institute database; http://www.jgi.doe.gov).

Amino Acid Sequence↗
PubMed2004

Multiple gene organization of pufferfish Fugu rubripes tropomyosin isoforms and tissue distribution of their transcripts.

The Japanese pufferfish, torafugu (Fugu rubripes), has a haploid genome of about 400 Mb in size, which has been sequenced to approximately 90% coverage. Here we identified six Fugu tropomyosin (TPM) gene sequences by using the BLASTN program and the sequence of the white croaker TPM1 gene in our collection against the draft assembly of the Fugu genomic sequence database. TPM2, TPM3 and TPM4 genes were identified together with a set of two potentially duplicated genes of TPM1 (TPM1-1 and TPM1-2) as described in our previous report and TPM4 (TPM4-1 and TPM4-2) newly found in this study. The expression patterns of these Fugu TPM genes were determined by reverse transcription polymerase chain reaction (RT-PCR). A phylogenetic tree was constructed using the deduced amino acid sequences, which were encoded by the exons common to all vertebrate TPM genes. This indicated that the Fugu TPM1 and TPM4 genes had resulted from a gene duplication in the fish evolutionary lineage.

Alternative Splicing↗
PubMed2025

Rare pathogenic NR2F2 (COUP-TFII) variants as potential etiological causes in pediatric patients with congenital heart diseases (CHDs).

OBJECTIVES: Congenital heart diseases (CHDs) are complex genetic disorders, and their genetic basis is not yet fully understood. Nuclear receptor subfamily 2 group F member 2 (NR2F2 or COUP-TFII) encodes a transcription factor which is expressed at high levels during mammalian development. Few studies have identified heterozygous and rare variants in the NR2F2 gene in individuals with CHD. This study aimed to evaluate the association between pathogenic genetic alterations in NR2F2 with CHD risk. METHODS: A case-control study was conducted on a group of 135 patients (83 boys and 52 girls) with various types of non-hereditary, isolated CHD who were undergoing open-heart surgery. Additionally, 95 matched healthy children without syndromic or isolated heart abnormalities were selected. RESULTS: Using Sanger sequencing, we identified 5 heterozygous single nucleotide variants in exons 2 and 3 of the NR2F2 gene. These variations were novel and not present in any genomic variation databases. Four of the variations were missense mutations (p.Pro159Arg, p.Ser329Phe, p.Qln338Pro, and p.Tyr348Ser) and one was a synonymous variant (p.G361 = ) in the coding region. Importantly, in silico results indicated that the missense variants had pathogenic effects on protein function. Additionally, the missense variants substantially altered the predicted structure of COUP-TFII. CONCLUSION: The results we obtained not only validate the correlation between NR2F2 mutations and CHDs but also have significant potential for guiding new preventive and therapeutic strategies. This could contribute to the advancement of medical interventions in the fields of cardiology and genetics.

Humans↗
PubMed2004

O-glycosylation in Toxoplasma gondii: identification and analysis of a family of UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases.

The initiation of mucin-type O-glycosylation is catalysed by a family of UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (EC 2.4.1.41). These enzymes are responsible for the transfer of N-acetylgalactosamine from the nucleotide sugar donor, UDP-GalNAc, to the hydroxyl group on specific serine or threonine residues in acceptor proteins. By screening a Toxoplasma gondii cDNA library, three distinct isoforms of the ppGalNAc-T gene family were cloned. Two additional isoforms were identified and partially cloned following analysis of the T. gondii genome sequence database. All of the cloned and identified ppGalNAc-T's are type II membrane proteins that share up to 50% amino acid sequence identity within the conserved catalytic domain. They each contain an N-terminal cytoplasmic domain, a hydrophobic transmembrane domain, and a lumenal domain; the latter consists of stem, catalytic, and lectin-like domains. Moreover, each of this ppGalNAc-T's contains important sequence motifs that are typical for this class of glycosyltransferases. These include a glycosyltransferase 1 motif containing the DXH sequence, a Gal/GalNAc-T motif, and the CLD and QXW sequence motifs located in alpha-, beta-, and gamma-repeats present within the lectin-like domain. The coding regions of T. gondii ppGalNAc-T1, -T2, and -T3 reside in multiple exons ranging in number from 6 to 10. Our results demonstrate that mucin-type O-glycosylation in T. gondii is catalysed by a multimember gene family, which is evolutionarily conserved from single-celled eukaryotes through nematodes and insects up to mammals. Taken together, this information creates the basis for future studies of the function of the ppGalNAc-T gene family in the pathobiology of this apicomplexan parasite.

Amino Acid Sequence↗
PubMed2026

Mature Tertiary Lymphoid Structures in Breast Cancers Are Associated With Antitumor Immunity and Better Prognosis.

Tertiary lymphoid structures (TLSs) are immune cells accumulated in nonlymphoid tissues, with an inner core of B cells encompassed by T cells. The aim of this study was to evaluate the clinical importance of mature TLSs in breast cancer, including their association with immunotherapy response and their role in modulating the tumor immune microenvironment. We analyzed histopathological data of 726 consecutive primary breast cancers and transcriptomic data of 824 breast cancer samples from the publicly available The Cancer Genome Atlas database to estimate the clinical and immunological values of mature TLSs in breast cancer. Additionally, we utilized pretreatment transcriptomic data of 69 patients with breast cancer from the publicly available I-SPY2 clinical trial to investigate the relation between TLS-related gene signatures and patient responses to immune checkpoint inhibitors. The existence of mature TLSs was identified in ⁓5.6% (41/726) of all patients with breast cancer (hormone receptor-positive human epidermal growth factor receptor-2 negative (HR+HER2-): 0.92%; triple-negative breast cancer (TNBC): 14.96%; and human epidermal growth factor receptor-2 positive (HER2+): 10.98%) and was independently associated with improved recurrence-free survival after adjusting for subtypes, tumor-infiltrating lymphocyte levels, and tumor stage after the multivariable Cox regression analysis in our patient cohort. Notably, the presence of mature TLSs was related to immune cell infiltration in our breast cancer patient cohort. In line with these findings, TLS-related gene signatures analyzed through transcriptomic data reliably reflected the existence of mature TLSs and were related to better clinical responses to immune checkpoint inhibitors in patients with breast cancer. In conclusion, our findings show that mature TLS formation is linked with immune cell infiltration, contributes to a favorable prognosis, and may function as a potential complementary biomarker for immunotherapy response in breast cancer.

Humans↗
PubMed2006

Schistosoma mansoni CBP/p300 has a conserved domain structure and interacts functionally with the nuclear receptor SmFtz-F1.

Metazoan species diversification in general and the adaptation of parasites to their life-style in particular are due, not only to the evolution of different structural or metabolic proteins, but also to changes in the expression patterns of the corresponding genes. In order to explore the conservation/divergence of transcriptional regulation in the platyhelminth parasite Schistosoma mansoni, we are studying the structures and functions of transcriptional mediators. CREB-binding protein (CBP) and p300 are closely related transcriptional coactivators that possess histone acetyltransferase (HAT) activity that can modify chromatin to an active relaxed state. They are also thought to link transcription factors to the basic transcriptional machinery and to act as integrators for different regulatory pathways. Here we describe the cloning and functional characterization of S. mansoni CBP. SmCBP1 comprises 2093 amino acids and displays a conserved modular domain structure. The HAT domain was shown to acetylate histones with a marked activity toward H4. Functional studies showed that SmCBP1 could interact physically with the nuclear receptor SmFtz-F1 and also potentiated its transcriptional activity in the CV-1 cell line. Screening of the EST and genomic sequence databases with the SmCBP1 sequence allowed us to characterize a second CBP gene in S. mansoni. SmCBP2 shows a high degree of sequence identity to SmCBP1, particularly in the HAT domain. Phylogenetic studies show that these peptides are more closely related to each other than to either mammalian CBP or p300, suggesting that they derive from a platyhelminth-specific duplication event. Both genes are expressed at all life-cycle stages, but differences in their relative expression and structural variations suggest that they play distinct roles in schistosome gene regulation.

Acetylation↗
PubMed2004

Mouse homolog of KIAA0143 protein: hearing deficit induces specific changes of expression in auditory brainstem neurons.

Hearing deficit induced by mechanical cochlear damage, intense noise or ototoxic drugs produces a variety of structural and functional changes in the inner ear and the auditory brainstem. In the present study, we identified a novel gene that has activity dependent plasticity in the superior olivary complex by using suppression subtractive hybridization. We cloned a gene that encodes mouse homolog of KIAA0143 protein, one derived from a series of unidentified human genes. This gene termed mKIAA0143 shows differential expression of mRNA in the lateral superior olive between mice with hearing deficit and those with normal hearing ability. The mRNA thus obtained encodes a unique membrane-bound protein that consists of 819 amino acids. The gene locus was mapped using genomic DNA databases to the mouse chromosome 15D1. Green fluorescent protein-tagged mKIAA0143 was expressed in COS-1 cells. It was amply seen in the cellular plasma membrane.

Acoustic Stimulation↗
PubMed2004

Expression analysis of the Toll-like receptor and TIR domain adaptor families of zebrafish.

The zebrafish genomic sequence database was analysed for the presence of genes encoding members of the Toll-like receptors (TLR) and interleukin receptors (IL-R) and associated adaptor proteins containing a TIR domain. The resulting predictions show the presence of one or more counterparts for the human TLR1, TLR2, TLR3, TLR4, TLR5, TLR7, TLR8, TLR9, IL-1R and IL-18R genes and one copy of the adaptor genes MyD88, MAL, TRIF and SARM. In contrast to data for the pufferfish Fugu rubripes, zebrafish has two genes that are highly similar to human TLR4. In addition, one fish-specific TLR group can be distinguished that is closely related to the Drosophila melanogaster Toll-9 gene. The sequence of cloned cDNAs for TLR4, TLR2 and MyD88 show the same intron-exon organisation as in the human counterparts. Expression analysis using reverse transcriptase-PCR (RT-PCR) shows that 17 of the predicted zebrafish TLR genes and all the genes encoding adaptor proteins are expressed in the adult stage. A subset of the TLR genes are expressed at higher levels in fish infected with the pathogen Mycobacterium marinum. The induced genes include the homologues of the human TLR1 and TLR2 genes, whose functions are associated with mycobacterial infections, underscoring the suitability of zebrafish as a model for analysis of the vertebrate innate immune system.

Animals↗
PubMed2004

A computational approach to measuring coherence of gene expression in pathways.

This study uses a computational approach to analyze coherence of expression of genes in pathways. Microarray data were analyzed with respect to coherent gene expression in a group of genes defined as a pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Our hypothesis is that genes in the same pathway are more likely to be coordinately regulated than a randomly selected gene set. A correlation coefficient for each pair of genes in a pathway was estimated based on gene expression in normal or tumor samples, and statistically significant correlation coefficients were identified. The coherence indicator was defined as the ratio of the number of gene pairs in the pathway whose correlation coefficients are significant, divided by the total number of gene pairs in the pathway. We defined all genes that appeared in the KEGG pathways as a reference gene set. Our analysis indicated that the mean coherence indicator of pathways is significantly larger than the mean coherence indicator of random gene sets drawn from the reference gene set. Thus, the result supports our hypothesis. The significance of each individual pathway of n genes was evaluated by comparing its coherence indicator with coherence indicators of 1000 random permutation sets of n genes chosen from the reference gene set. We analyzed three data sets: two Affymetrix microarrays and one cDNA microarray. For each of the three data sets, statistically significant pathways were identified among all KEGG pathways. Seven of 96 pathways had a significant coherence indicator in normal tissue and 14 of 96 pathways had a significant coherence indicator in tumor tissue in all three data sets. The increase in the number of pathways with significant coherence indicators may reflect the fact that tumor cells have a higher rate of metabolism than normal cells. Five pathways involved in oxidative phosphorylation, ATP synthesis, protein synthesis, or RNA synthesis were coherent in both normal and tumor tissue, demonstrating that these are essential genes, a high level of expression of which is required regardless of cell type.

Databases, Genetic↗
PubMed2004

Mitochondrial DNA 3644T-->C mutation associated with bipolar disorder.

Mitochondrial dysfunction associated with mutant mitochondrial DNA (mtDNA) has been suggested in bipolar disorder, and comorbidity with neurodegenerative diseases was often noted. We examined the entire sequence of mtDNA in six subjects with bipolar disorder having comorbid somatic symptoms suggestive of mitochondrial disorders and found several uncharacterized homoplasmic nonsynonymous nucleotide substitutions of mtDNA. Of these, 3644C was found in 5 of 199 patients with bipolar disorder but in none of 258 controls (p = 0.015). The association was significant in the extended samples [bipolar disorder, 9/630 (1.43%); controls, 1/734 (0.14%); p = 0.007]. On the other hand, only 5 of 25 family members with this mutation developed bipolar disorder, of which 4 patients with 3644C had comorbid physical symptoms. The 3644T-->C mutation converts amino acid 113, valine, to alanine in the NADH-ubiquinone dehydrogenase subunit I, a subunit of complex I, and 113 valine is well conserved from Drosophila to 61 mammalian species. Using transmitochondrial cybrids, 3644T-->C was shown to decrease mitochondrial membrane potential and complex I activity compared with haplogroup-matched controls. According to human mitochondrial genome polymorphism databases, 3644C was not found in centenarians but was found in 3% of patients with Alzheimer disease and 2% with Parkinson disease. The result of modest functional impairment caused by 3644T-->C suggests that this mutation could increase the risk for bipolar disorder.

Adolescent↗