The genetic determinants of severe hypertriglyceridemia (HTG; MIM 144650) in adults are poorly defined. We therefore resequenced 3 candidate genes, namely LPL, APOC2, and APOA5, to search for accumula Show more
The genetic determinants of severe hypertriglyceridemia (HTG; MIM 144650) in adults are poorly defined. We therefore resequenced 3 candidate genes, namely LPL, APOC2, and APOA5, to search for accumulation of missense mutations in patients with severe HTG compared with normolipidemic subjects. We resequenced >2 million base pairs of genomic DNA from 110 nondiabetic patients with severe HTG and determined the prevalence of coding sequence variants compared with 472 age- and sex-matched normolipidemic controls. We found: (1) heterozygous mutations (LPL p.Q-12E >11X, p.D25H, p.W86R, p.G188E, p.I194T and p.P207L; APOC2 p.K19T and IVS2-30G>A) in 10.0% of severe HTG patients compared with 0.2% of controls (carrier odds ratio [OR] 52, 95% confidence interval [CI] 8.6 to 319); and (2) an association of the APOA5 p.S19W missense variant with severe HTG (carrier OR 5.5 95% CI 3.3 to 9.1). Furthermore, either rare mutations or the APOA5 p.S19W variant were found in 41.8% of HTG subjects compared with 8.9% of controls (carrier OR 7.4, 95% CI 4.5 to 12.0). Also, heterozygotes for rare mutations had a significantly reduced plasma triglyceride response to fibrate monotherapy. Both common and rare DNA variants in candidate genes were found in a substantial proportion of severe HTG patients. The findings underscore the value of candidate gene resequencing to understand the genetic contribution in complex lipoprotein and metabolic disorders. Show less
Polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) was used to explore the distribution of apolipoprotein A5 gene -1131T>C and 56C>G polymorphisms in 257 healthy Hubei Han Show more
Polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) was used to explore the distribution of apolipoprotein A5 gene -1131T>C and 56C>G polymorphisms in 257 healthy Hubei Han people. The following results were calculated: the frequency of -1131TT genotype was 50.9%, far more than that of -1131TC and -1131CC genotypes (32.9% and 16.2%, respectively). The number of T allele carriers was higher than that of C carriers, and their respective frequencies were 0.675 and 0.325. There were 56GG and 56GC genotypes, but only 2 individuals in all subjects carried the G allele, the frequency of which was low than 5%. Furthermore, the frequency of genotypes and alleles in apoa5 -1131T>C and 56C>G polymorphisms was clearly different from other races and areas. We conclude that the apoa5 -1131T>C variation should be considered a single nucleotide polymorphism, but the 56C>G variation should be considered as a mutation instead. Show less
Patients with diabetic nephropathy (DN) have increased plasma fasting triglyceride (TG) levels, and most prospective studies report that elevated TG precedes DN. TG-rich lipoprotein particles might pr Show more
Patients with diabetic nephropathy (DN) have increased plasma fasting triglyceride (TG) levels, and most prospective studies report that elevated TG precedes DN. TG-rich lipoprotein particles might promote progression of DN. To test the hypothesis that elevated TG levels contribute to the development of DN, one may examine whether a polymorphism strongly associated with TG levels affects DN risk. The apolipoprotein A5 (apoA5) -1131T-->C polymorphism has a large effect on the TG level, and all three genotypes are relatively common in East Asians. Therefore, we sought to examine the association of this polymorphism with DN. We genotyped the apoA5 -1131T-->C polymorphism in a case-control study involving 367 Chinese Type 2 diabetes patients with DN and 382 without DN, as well as 198 subjects without diabetes. Mean fasting TG levels were higher in CC than in TT carriers by 41%, 54%, and 62% in each of the three subject groups, respectively. However, the genotype distributions did not differ between patients with and without nephropathy (P=.69). Therefore, these results weigh against the hypothesis that high fasting TG per se causes DN. The strong association between TG level and DN may be due to a factor that is usually closely linked to TG level but that is not affected by the apoA5 polymorphism. Show less
The neuronal ceroid lipofuscinoses are pediatric neurodegenerative diseases with common clinical features. Of the nine clinical variants (CLN1-CLN9), six have been genetically identified. Most variant Show more
The neuronal ceroid lipofuscinoses are pediatric neurodegenerative diseases with common clinical features. Of the nine clinical variants (CLN1-CLN9), six have been genetically identified. Most variants manifest cell death and dysregulated sphingolipid metabolism, suggesting the proteins defective in these disorders may interact along one pathway. NCL patient-derived cell lines exhibit cell growth and apoptotic defects that reverse following transfection with the wild-type gene. The membrane-bound proteins CLN3, CLN6, and CLN8 complement each other, as do CLN1 and CLN2 proteins, with respect to growth and apoptosis. The CLN2 protein also corrects growth and apoptosis in CLN3-, CLN6-, and CLN8-deficient cell lines. Neither CLN1-deficient nor CLN2-deficient growth defects are corrected by CLN3, CLN6, and CLN8 proteins. CLN2, CLN3, CLN6, and CLN8 proteins co-immunoprecipitate and co-localize to early and/or recycling endosomes and lipid rafts. Additionally, CLN2p and CLN1p co-immunoprecipitate. The work presented supports interactions between NCL proteins occurring at multiple points along one pathway. Show less
To investigate the expression of PSD-93 mRNA and NR2B mRNA in the brain tissue from the patients with epilepsy so as to explore the possible mechanisms of the pathogenesis of the epilepsy. Fifty-six p Show more
To investigate the expression of PSD-93 mRNA and NR2B mRNA in the brain tissue from the patients with epilepsy so as to explore the possible mechanisms of the pathogenesis of the epilepsy. Fifty-six patients with epilepsy were divided into intractable epilepsy (IE) and non-intractable epilepsy (NIE) groups. cDNA microarrays prepared from the brain tissues obtained from these two groups were scanned and comparison to those from the non-epileptogenic control (C) was made. Expression level of PSD-93mRNA and NR2BmRNA were examined by reverse transcription polymerase chain reaction (GAPDH gene, internal control). Expression ratio (target gene/GAPDH) was used to evaluate each gene relative expression level. The cDNA microarray analysis showed that the expression of PSD-93 mRNA related to the function of NMDAR-NO signal transduction pathway was significantly higher in epilepsy patients than those in the controlled group. The results of RT-PCR were consistent with those of the cDNA microarrays. The relative expression ratio of PSD-93 in patients with non-epileptogenic control, NIE, and IE was 0.159, 0.368, and 0.341, respectively. Correspondingly, that of NR2B was 0.198, 0.738, and 0.903, respectively. The expressions of PSD-93 and NR2B in the NIE and IE were significantly higher than those of control, respectively (P<0.05). However, there was no significantly difference the expression of PSD-93 between NIE and IE. (P>0.05), neither do that of NR2B (P>0.05). The upregulated expressions of PSD-93 mRNA and NR2BmRNA may be involved in the pathogenesis of epilepsy. Show less
Current staging methods are inadequate for predicting the outcome of treatment of non-small-cell lung cancer (NSCLC). We developed a five-gene signature that is closely associated with survival of pat Show more
Current staging methods are inadequate for predicting the outcome of treatment of non-small-cell lung cancer (NSCLC). We developed a five-gene signature that is closely associated with survival of patients with NSCLC. We used computer-generated random numbers to assign 185 frozen specimens for microarray analysis, real-time reverse-transcriptase polymerase chain reaction (RT-PCR) analysis, or both. We studied gene expression in frozen specimens of lung-cancer tissue from 125 randomly selected patients who had undergone surgical resection of NSCLC and evaluated the association between the level of expression and survival. We used risk scores and decision-tree analysis to develop a gene-expression model for the prediction of the outcome of treatment of NSCLC. For validation, we used randomly assigned specimens from 60 other patients. Sixteen genes that correlated with survival among patients with NSCLC were identified by analyzing microarray data and risk scores. We selected five genes (DUSP6, MMD, STAT1, ERBB3, and LCK) for RT-PCR and decision-tree analysis. The five-gene signature was an independent predictor of relapse-free and overall survival. We validated the model with data from an independent cohort of 60 patients with NSCLC and with a set of published microarray data from 86 patients with NSCLC. Our five-gene signature is closely associated with relapse-free and overall survival among patients with NSCLC. Show less
Mark Tarnopolsky, Stuart Phillips, Gianni Parise+6 more · 2007 · The journals of gerontology. Series A, Biological sciences and medical sciences · Oxford University Press · added 2026-04-24
Methodological issues relevant to studies using microarrays and reverse transcription-polymerase chain reaction (RT-PCR) in human aging have rarely been evaluated. Because aging may accentuate biologi Show more
Methodological issues relevant to studies using microarrays and reverse transcription-polymerase chain reaction (RT-PCR) in human aging have rarely been evaluated. Because aging may accentuate biological differences between muscles, we compared transcriptome expression patterns, targeted messenger RNA (mRNA) abundance, strength, and muscle fiber type in the right and left legs of older adults. Muscle biopsies were taken from each Vastus lateralis in eight older (71 +/- 2 years) men, and isometric strength was determined. Samples were analyzed using an Affymetrix gene array, ATPase histochemistry, and RT-PCR for mRNA species involved in metabolism, apoptosis, vascular growth, and antioxidant status. Microarray analysis found that 31 of 5499 genes (0.6%) were significantly different between legs (negative log of the p value [NLOGP] >/= 2.0, but fold < 1.5), with only one gene, jumonji domain containing 1C (JMJD1C), being significantly different by >/= 1.50-fold. None of the mRNA species, or muscle fiber type, size, or strength, was different between legs. These findings are important for the design and analysis of studies using muscle data in older adults. Show less
Demyelinating diseases, such as multiple sclerosis, are characterized by the loss of the myelin sheath around neurons, owing to inflammation and gliosis in the central nervous system (CNS). Current tr Show more
Demyelinating diseases, such as multiple sclerosis, are characterized by the loss of the myelin sheath around neurons, owing to inflammation and gliosis in the central nervous system (CNS). Current treatments therefore target anti-inflammatory mechanisms to impede or slow disease progression. The identification of a means to enhance axon myelination would present new therapeutic approaches to inhibit and possibly reverse disease progression. Previously, LRR and Ig domain-containing, Nogo receptor-interacting protein (LINGO-1) has been identified as an in vitro and in vivo negative regulator of oligodendrocyte differentiation and myelination. Here we show that loss of LINGO-1 function by Lingo1 gene knockout or by treatment with an antibody antagonist of LINGO-1 function leads to functional recovery from experimental autoimmune encephalomyelitis. This is reflected biologically by improved axonal integrity, as confirmed by magnetic resonance diffusion tensor imaging, and by newly formed myelin sheaths, as determined by electron microscopy. Antagonism of LINGO-1 or its pathway is therefore a promising approach for the treatment of demyelinating diseases of the CNS. Show less
It is unclear whether cardiac hypertrophy and hypertrophy-related pathways will be induced by long-term intermittent hypoxia. Thirty-six Sprague-Dawley rats were randomly assigned into three groups: n Show more
It is unclear whether cardiac hypertrophy and hypertrophy-related pathways will be induced by long-term intermittent hypoxia. Thirty-six Sprague-Dawley rats were randomly assigned into three groups: normoxia, and long-term intermittent hypoxia (12% O(2), 8 h per day) for 4 weeks (4WLTIH) or for 8 weeks (8WLTIH). Myocardial morphology, trophic factors and signalling pathways in the three groups were determined by heart weight index, histological analysis, Western blotting and reverse transcriptase-polymerase chain reaction from the excised left ventricle. The ratio of whole heart weight to body weight, the ratio of left ventricular weight to body weight, the gross vertical cross-section of the heart and myocardial morphological changes were increased in the 4WLTIH group and were further augmented in the 8WLTIH group. In the 4WLTIH group, tumour necrosis factor-alpha(TNFalpha), insulin-like growth factor (IGF)-II, phosphorylated p38 mitogen-activated protein kinase (P38), signal transducers and activators of transcription (STAT)-1 and STAT-3 were significantly increased in the cardiac tissues. However, in the 8WLTIH group, in addition to the above factors, interleukin-6, mitogen-activated protein kinase (MEK)5 and extracellular signal-regulated kinase (ERK)5 were significantly increased compared with the normoxia group. We conclude that cardiac hypertrophy associated with TNFalpha and IGF-II was induced by intermittent hypoxia. The longer duration of intermittent hypoxia further activated the eccentric hypertrophy-related pathway, as well as the interleukin 6-related MEK5-ERK5 and STAT-3 pathways, which could result in the development of cardiac dilatation and pathology. Show less
Hypertrophic cardiomyopathy is typically inherited in an autosomal dominant pattern and has a variable age of onset and prognosis. Mutations in the myosin-binding protein C (MYBPC3) gene are one of th Show more
Hypertrophic cardiomyopathy is typically inherited in an autosomal dominant pattern and has a variable age of onset and prognosis. Mutations in the myosin-binding protein C (MYBPC3) gene are one of the most frequent genetic causes of the disease. Patients with MYBPC3 mutations generally have a late onset and a relatively good prognosis. We report here more than 20 Old Order Amish children with severe neonatal hypertrophic cardiomyopathy caused by a novel homozygous splice site mutation in the MYBPC3 gene. The affected children typically presented with signs and symptoms of congestive heart failure during the first 3 weeks of life. Echocardiography revealed hypertrophic non-obstructive cardiomyopathy. These children had a life span averaging 3-4 months. All patients died from heart failure before 1 year of age unless they received a heart transplant. A genome-wide mapping study was performed in three patients. The disease related gene was localized to a 4.6 Mb region on chromosome 11p11.2-p11.12. This homozygous block contained MYBPC3, a previously identified cardiomyopathy related gene. We identified a novel homozygous mutation, c.3330 + 2T > G, in the splice-donor site of MYBPC3 intron 30. The mutation resulted in skipping of the 140-bp exon 30, which led to a frame shift and premature stop codon in exon 31 (p.Asp1064GlyfsX38). We have found a substantial incidence of this phenotype in Old Order Amish communities. It is also concerning that many unidentified heterozygous individuals who are at risk for development of hypertrophic cardiomyopathy do not receive proper medical attention in the communities. Show less
To study the disease-causing gene mutation in Chinese patients with familial hypertrophic cardiomyopathy (FHC) and to analyze the correlation between the genotype and the phenotype. Peripheral blood s Show more
To study the disease-causing gene mutation in Chinese patients with familial hypertrophic cardiomyopathy (FHC) and to analyze the correlation between the genotype and the phenotype. Peripheral blood samples were collected from 40 members from a family affected with FHC, and 120 healthy volunteers. PCR was performed to analyze the exons and flanking introns of the cardiac troponin T gene (TNNT2), beta-myosin heavy chain gene (MYH7), and myosin-binding protein C gene (MYBPC3) and the products were sequenced. The clinical data including symptom, physical examination, echocardiography and electrocardiography were collected. A 14035c > t mutation, which causes a missense mutation (R130C) in exon 10 of TNNT2 gene were identified in 4 family members, including the proband, female, aged 53, with the onset at the age of 30. The 4 persons with the 14035c > t mutation, all FHC patients, presented left ventricular dysfunction with a penetrance of 100%. Two of the patients died of sudden cardiac death during follow-up. No mutation was identified in the MYH7 and MYBPC3 genes. The 14035c > t mutation of TNNT2 gene is the causal mutation of FHC which is associated with malignant phenotype with a penetrance of 100%. It is a reasonable procedure in HCM patients with malignant phenotype to screen mutation in the TNNT2 gene. Show less
To study the disease-causing gene mutation in Chinese patients with hypertrophic cardiomyopathy (HCM) and to analyze the genotype and phenotype correlation. One family (n = 27) affected with HCM were Show more
To study the disease-causing gene mutation in Chinese patients with hypertrophic cardiomyopathy (HCM) and to analyze the genotype and phenotype correlation. One family (n = 27) affected with HCM were chosen for the study. The full encoding exons and flanking sequences of beta-myosin heavy chain gene (MYH7) and cardiac myosin-binding protein C gene (MYBPC3) were amplified with PCR and the products were sequenced. The clinical data including symptom, physical, echocardiography and electrocardiography examinations were collected. We identified a 13261 G > A mutation, which causes a missense mutation (G758D) in exon 23 of MYBPC3 in 9 family members. One mutation carrier suffered from dilated cardiomyopathy (DCM) with asymmetric interventricular septal hypertrophy (14 mm). Another mutation carrier was diagnosed as HCM. The 13261 G > A mutation is associated with a DCM-like HCM and HCM phenotype in this Chinese family affected with HCM. Show less
Directional migration is important in wound healing by epithelial cells. Recent studies have shown that polarity proteins such as mammalian Partitioning-defective 6 (Par6), atypical protein kinase C ( Show more
Directional migration is important in wound healing by epithelial cells. Recent studies have shown that polarity proteins such as mammalian Partitioning-defective 6 (Par6), atypical protein kinase C (aPKC) and mammalian Discs large 1 (Dlg1) are crucial not only for epithelial apico-basal polarity, but also for directional movement. Here, we show that the protein associated with Lin seven 1 (PALS1)-associated tight junction protein (PATJ), another evolutionarily conserved polarity protein, is also required for directional migration by using a wound-induced migration assay. In addition, we found that aPKC and Par3 localize to the leading edge during migration of epithelia and that PATJ regulates their localization. Furthermore, our results show that microtubule-organizing centre orientation is disrupted in PATJ RNA interference (RNAi) MDCKII (Madin-Darby canine kidney II) cells during migration. Together, our data indicate that PATJ controls directional migration by regulating the localization of aPKC and Par3 to the leading edge. The migration defect in PATJ RNAi cells seems to be due to the disorganization of the microtubule network induced by mislocalization of polarity proteins. Show less
Transcription-induced chimerism, a mechanism involving the transcription and intergenic splicing of two consecutive genes, has recently been estimated to account for approximately 5% of the human tran Show more
Transcription-induced chimerism, a mechanism involving the transcription and intergenic splicing of two consecutive genes, has recently been estimated to account for approximately 5% of the human transcriptome. Despite this prevalence, the regulation and function of these fused transcripts remains largely uncharacterised. We identified three novel transcription-induced chimeras resulting from the intergenic splicing of a single RNA transcript incorporating the two neighbouring 3p21.3 tumour suppressor locus genes, RBM6 and RBM5, which encode the RNA Binding Motif protein 6 and RNA Binding Motif protein 5, respectively. Each of the three novel chimeric transcripts lacked exons 3, 6, 20 and 21 of RBM6 and exon 1 of RBM5. Differences between the transcripts were associated with the presence or absence of exon 4, exon 5 and a 17 nucleotide (nt) sequence from intron 10 of RBM6. All three chimeric transcripts incorporated the canonical splice sites from both genes (excluding the 17 nt intron 10 insertion). Differential expression was observed in tumour tissue compared to non-tumour tissue, and amongst tumour types. In breast tumour tissue, chimeric expression was associated with elevated levels of RBM6 and RBM5 mRNA, and increased tumour size. No protein expression was detected by in vitro transcription/translation. These results suggest that RBM6 mRNA experiences altered co-transcriptional gene regulation in certain cancers. The results also suggest that RBM6-RBM5 transcription-induced chimerism might be a process that is linked to the tumour-associated increased transcriptional activity of the RBM6 gene. It appears that none of the transcription-induced chimeras generates a protein product; however, the novel alternative splicing, which affects putative functional domains within exons 3, 6 and 11 of RBM6, does suggest that the generation of these chimeric transcripts has functional relevance. Finally, the association of chimeric expression with breast tumour size suggests that RBM6-RBM5 chimeric expression may be a potential tumour differentiation marker. Show less
Hong-Ying Wang, Li Zhou, Jian-Fang Gui · 2007 · Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology · Elsevier · added 2026-04-24
Previous studies have demonstrated that germinal vesicle of amphibian oocyte contains small nuclear ribonucleoprotein polypeptide C (SNRPC). In this study, a putative member of SNRPC was identified fr Show more
Previous studies have demonstrated that germinal vesicle of amphibian oocyte contains small nuclear ribonucleoprotein polypeptide C (SNRPC). In this study, a putative member of SNRPC was identified from Carassius auratus gibelio oocyte cDNA library. Its full-length cDNA has an open reading frame of 201 nt for encoding a peptide of 66 aa, a short 5'-UTR of 19 nt and a long 3'-UTR of 347 nt including a polyadenylation signal and poly- (A) tail, and the deduced amino acid sequence has 47% identity with the C-terminal of the zebrafish small nuclear ribonucleoprotein polypeptide C. Western blot analysis revealed its oocyte-specific expression. Immunofluorescence localization indicated that its gene product localized to numerous nucleoli within the oocytes and showed dynamic changes with the nucleoli during oocyte maturation. RT-PCR and Western blot analysis further revealed its constant presence in the oocytes and in the embryos until hatching. The data suggested that the newly identified CagOSNRPC might be a nucleolar protein. Show less
Ubiquitination and the degradation of the large subunit of RNA polymerase II, Rpb1, is not only involved in DNA damage-induced arrest but also in other transcription-obstructing events. However, the u Show more
Ubiquitination and the degradation of the large subunit of RNA polymerase II, Rpb1, is not only involved in DNA damage-induced arrest but also in other transcription-obstructing events. However, the ubiquitin ligases responsible for DNA damage-independent processes in mammalian cells remain to be identified. Here, we identified Wwp2, a mouse HECT domain ubiquitin E3 ligase, as a novel ubiquitin ligase of Rpb1. We found that Wwp2 specifically interacted with mouse Rpb1 and targeted it for ubiquitination both in vitro and in vivo. Interestingly, the interaction with and ubiquitination of Rpb1 was dependent neither on its phosphorylation state nor on DNA damage. However, the enzymatic activity of Wwp2 was absolutely required for its ubiquitin modification of Rpb1. Furthermore, our study indicates that the interaction between Wwp2 and Rpb1 was mediated through WW domain of Wwp2 and C-terminal domain of Rpb1, respectively. Strikingly, downregulation of Wwp2 expression compromised Rpb1 ubiquitination and elevated its intracellular steady-state protein level significantly. Importantly, we identified six lysine residues in the C-terminal domain of Rpb1 as ubiquitin acceptor sites mediated by Wwp2. These results indicate that Wwp2 plays an important role in regulating expression of Rpb1 in normal physiological conditions. Show less
Quantitative and qualitative differences in intralumenal bile acids may affect cholesterol absorption and metabolism. To test this hypothesis, 2 cross-over outpatient studies were conducted in adults Show more
Quantitative and qualitative differences in intralumenal bile acids may affect cholesterol absorption and metabolism. To test this hypothesis, 2 cross-over outpatient studies were conducted in adults with apo-A IV 1/1 or apo-E 3/3 genotypes. Study 1 included 11 subjects 24 to 37 years of age, taking 15 mg/kg/day chenodeoxycholic acid (CDCA) or no bile acid for 20 days while being fed a controlled diet. Study 2 included 9 adults 25 to 38 years of age, taking 15 mg/kg/day deoxycholic acid (DCA) or no bile acid, following the same experimental design and procedures as study 1. CDCA had no effect on plasma lipid concentrations, whereas DCA decreased (P < 0.05) plasma high-density lipoprotein (HDL)-cholesterol and tended to decrease (P = 0.15) low-density lipoprotein (LDL)-cholesterol. CDCA treatment enriched (P < 0.0001) bile with CDCA and increased cholesterol concentration in micelles, whereas meal-stimulated bile acid concentrations were decreased. DCA treatment enriched (P < 0.0001) bile with DCA and tended to increase intralumenal cholesterol solubilized in micelles (P = 0.06). No changes were found in cholesterol absorption, free cholesterol fractional synthetic rate (FSR), or 3-hydroxy-3 methylglutaryl (HMG) CoA reductase and LDL receptor messenger ribonucleic acid (mRNA) levels after CDCA treatment. DCA supplementation tended to decrease cholesterol absorption and reciprocally increase FSR and HMG CoA reductase and LDL receptor mRNA levels. Results of these 2 studies suggest that the solubilization of cholesterol in the intestinal micelles is not a rate-limiting step for its absorption. Show less
It has been shown that adenovirus-mediated overexpression of human ApoAV (hApoAV) in C57BL/6 mice results in decreased plasma triglyceride (TG) and total cholesterol (TC) levels with a major reduction Show more
It has been shown that adenovirus-mediated overexpression of human ApoAV (hApoAV) in C57BL/6 mice results in decreased plasma triglyceride (TG) and total cholesterol (TC) levels with a major reduction occurring in the HDL fraction. In order to study the effect of ApoAV on hypercholesterolemic mice, an adenoviral vector expressing hApoAV was constructed and injected into ApoE deficient mice. High levels of hApoAV mRNA in the liver and ApoAV proteins in the liver and plasma were detected. The treatment reduced plasma TG levels by 50% and 75%, and TC levels by 45% and 58% at day 3 and 7, respectively, after treatment as compared with a control group treated with Ad-hAP (human alkaline phosphatase). Plasma HDL-C levels remained unaltered, which were different from normolipidemic mice. These findings suggest that ApoAV might serve as a therapeutic agent for hyperlipidemic disorder. Show less
Haplotype-based association analysis has been recognized as a tool with high resolution and potentially great power for identifying modest etiological effects of genes. However, in practice, its effic Show more
Haplotype-based association analysis has been recognized as a tool with high resolution and potentially great power for identifying modest etiological effects of genes. However, in practice, its efficacy has not been as successfully reproduced as expected in theory. One primary cause is that such analysis tends to require a large number of parameters to capture the abundant haplotype varieties, and many of those are expended on rare haplotypes for which studies would have insufficient power to detect association even if it existed. To concentrate statistical power on more-relevant inferences, in this study, we developed a regression-based approach using clustered haplotypes to assess haplotype-phenotype association. Specifically, we generalized the probabilistic clustering methods of Tzeng to the generalized linear model (GLM) framework established by Schaid et al. The proposed method uses unphased genotypes and incorporates both phase uncertainty and clustering uncertainty. Its GLM framework allows adjustment of covariates and can model qualitative and quantitative traits. It can also evaluate the overall haplotype association or the individual haplotype effects. We applied the proposed approach to study the association between hypertriglyceridemia and the apolipoprotein A5 gene. Through simulation studies, we assessed the performance of the proposed approach and demonstrate its validity and power in testing for haplotype-trait association. Show less
Recently, a T/C polymorphism of the promoter region of the APOA5 gene at position -1131 and a G/T polymorphism at position 553 were found to be associated with increased levels of plasma triglyceride. Show more
Recently, a T/C polymorphism of the promoter region of the APOA5 gene at position -1131 and a G/T polymorphism at position 553 were found to be associated with increased levels of plasma triglyceride. Triglyceride plays a role in coronary artery disease (CAD), so this case-control study tested for a possible link between these two APOA5 polymorphisms, their common haplotypes and the risk of CAD. The subjects included 211 CAD patients and 677 unrelated controls. A significantly higher level of triglycerides and a lower level of high-density lipoprotein cholesterol (HDL-C) were noted for carriers with -1131C than for non-carriers (P<0.001 and 0.013, respectively) among controls. Plasma triglyceride levels were significantly higher (P=0.014) in controls with genotypes that contained the c.553T allele than in homozygotes for the G allele. Subjects homozygous for the wild-type haplotype had significantly lower triglyceride levels and higher HDL-C levels than subjects with all other haplotype pairs. The -1131C homozygous carriers and c.553T heterozygous carriers were found more frequently in 211 patients with CAD than in the 317 age/sex-matched controls (P=0.008 and 0.023, respectively) in univariate analysis. The significant association between c.553T allele carriers with CAD remained in multivariate regression analysis (OR, 1.79; CI, 1.07-3.00; P=0.028), after adjustments were made for other risk factors. Notably, haplotype analysis further verified that the APOA5 -1131C and c.553T bi-loci haplotype was significantly overpresented in CAD, as compared to the controls. These results indicate that the variants of APOA5 gene modulate plasma triglyceride and may use them to predict CAD susceptibility in Taiwanese Chinese. Show less
Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. In DN patients, triglyceride (TG) level is elevated and lipoprotein lipase (LPL) activity, which hydrolyzes TG, is decreased. Show more
Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. In DN patients, triglyceride (TG) level is elevated and lipoprotein lipase (LPL) activity, which hydrolyzes TG, is decreased. The LPL S447X and apolipoprotein E (APOE) exon 4 polymorphisms affect TG levels, and the APOC3 -455T>C polymorphism affects LPL activity. Our aim was to examine the association of these polymorphisms with nephropathy in type 2 diabetes. We examined these polymorphisms in a case-control study of type 2 diabetic patients including 374 with DN and 392 without DN. LPL 447X-containing genotypes (447X+) were significantly decreased in DN patients [18.6 vs 25.6%, odds ratio (OR) = 0.66, p = 0.02], as were APOE epsilon3/epsilon3 genotypes (64.8 vs 73.1%, OR = 0.68, p = 0.01). In addition, combinations of genotypes [APOE epsilon3/epsilon3 and LPL 447X+ (OR = 0.56), APOC3 CC and LPL 447X+ (OR = 0.31), APOE epsilon3/epsilon3 and APOC3 CC (OR = 0.61] were protective for DN compared with the most common combination of the respective polymorphisms. Our findings suggest the importance of interactions among lipid genes in modulating the risk of DN. Show less
Both G1 and mitotic cyclins have been implicated in regulating Candida albicans filamentous growth. We have investigated the functions of Grr1 whose orthologue in Saccharomyces cerevisiae is known to Show more
Both G1 and mitotic cyclins have been implicated in regulating Candida albicans filamentous growth. We have investigated the functions of Grr1 whose orthologue in Saccharomyces cerevisiae is known to mediate ubiquitin-dependent degradation of the G1 cyclins Cln1 and Cln2. Here, we report that deleting C. albicans GRR1 causes significant stabilization of two G1 cyclins Ccn1 and Cln3 and pseudohyphal growth. grr1Delta cells are highly heterogeneous in length and many of them fail to separate after cytokinesis. Interestingly, some isolated rod-like G1 cells of similar sizes are present in the grr1Delta culture. Time-lapse microscopy revealed that the rod-shaped G1 cells first grew exclusively in width before budding and then the bud grew exclusively by apical extension until after cytokinesis, yielding rod-like daughter cells. Consistently, actin patches persistently localize to the bud tip until around the time of cytokinesis. Despite the pseudohyphal phenotype, grr1Delta cells respond normally to hyphal induction. Hyperphosphorylated Cln3 isoforms accumulate in grr1Delta cells, indicating that Grr1 selectively mediates their degradation in wild-type cells. grr1Delta pseudohyphal growth requires neither Hgc1 nor Swel, two important regulators of cell morphogenesis. Furthermore, the cellular level of Hof1, a protein having a role in cytokinesis, is also significantly increased in grr1Delta cells. Show less
Martyn J James, Elina Järvinen, Xiu-Ping Wang+1 more · 2006 · Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research · added 2026-04-24
We compared gene expression profiles between Runx2 null mutant mice and their wildtype littermates. Most Runx2-dependent genes in bones were different from those in teeth, implying that the target gen Show more
We compared gene expression profiles between Runx2 null mutant mice and their wildtype littermates. Most Runx2-dependent genes in bones were different from those in teeth, implying that the target genes of Runx2 are tissue-dependent. In vitro experiments determined that Runx2 is a part of the FGF and BMP signaling pathways in tooth and bone development, respectively. Runx2 (Cbfa1) is expressed in the neural crest-derived mesenchyme of developing bone and tooth. Runx2 homozygous null mice lack bone through a failure in osteoblast differentiation and have arrested tooth development at the late bud stage. The aim of this study was to discover and compare the identities and the roles of Runx2 target genes in bone and tooth development. Wildtype and Runx2-/- tissue was collected from mouse embryos, and gene expression was compared by Affymetrix microarray analysis and radioactive in situ hybridization of embryonic tissue sections (E12-E14). Induction of target genes by growth factors in bone and tooth tissue was studied using in vitro experiments, including a novel method involving hanging-drop cultures and RT-PCR. Thirteen bone and four tooth genes were identified that are Runx2-dependent. The identities of these genes do not significantly overlap between bone and tooth, indicating tissue specificity of several genes regulated by Runx2. Genes downregulated in bone development in Runx2 null mutants were Bambi, Bmp4, Bono1, Dkk1, Fgf receptor1, Gli1, Lef1, Patched, Prostaglandin F receptor1, Tcf1, Tgfbeta1, Wnt10a, and Wnt10b. Several of these genes were induced by BMPs in bone tissue in a Runx2-independent manner. Genes downregulated in tooth development were Dkk1, Dusp6, Enpp1, and Igfbp3. These genes were all induced by fibroblast growth factors (FGFs) in dental tissue. FGF-induction of Dkk1 was completely dependent on Runx2 function. The contrasting identities and distinctive mechanisms that stimulate the expression of Runx2-dependent genes in bone and tooth development imply that the developmental roles of Runx2 in these separate tissues are different. In tooth development, Dkk1 may be a direct transcriptional target of Runx2. Bone genes were stimulated by BMP4 before the formation of the ossification center, suggesting that BMPs may mediate the early epithelial-mesenchymal interactions involved in bone formation. Show less
LINGO-1 is a CNS-specific protein and a functional component of the NgR1/p75/LINGO-1 and NgR1/TAJ(TROY)/LINGO-1 signaling complexes that mediate inhibition of axonal outgrowth. These receptor complexe Show more
LINGO-1 is a CNS-specific protein and a functional component of the NgR1/p75/LINGO-1 and NgR1/TAJ(TROY)/LINGO-1 signaling complexes that mediate inhibition of axonal outgrowth. These receptor complexes mediate the axonal growth inhibitory effects of Nogo, myelin-associated glycoprotein (MAG) and oligodendrocyte-myelin glycoprotein (OMgp) via RhoA activation. Soluble LINGO-1 (LINGO-1-Fc), which acts as an antagonist of these pathways by blocking LINGO-1 binding to NgR1, was administered to rats after dorsal or lateral hemisection of the spinal cord. LINGO-1-Fc treatment significantly improved functional recovery, promoted axonal sprouting and decreased RhoA activation and increased oligodendrocyte and neuronal survival after either rubrospinal or corticospinal tract transection. These experiments demonstrate an important role for LINGO-1 in modulating axonal outgrowth in vivo and that treatment with LINGO-1-Fc can significantly enhance recovery after spinal cord injury. Show less
Extracellular signal-regulated protein kinase (ERK) 5 is a mitogen-activated protein kinase (MAPK) that is activated by dual phosphorylation via a unique MAPK/ERK kinase 5, MEK5. The physiological imp Show more
Extracellular signal-regulated protein kinase (ERK) 5 is a mitogen-activated protein kinase (MAPK) that is activated by dual phosphorylation via a unique MAPK/ERK kinase 5, MEK5. The physiological importance of this signaling cascade is underscored by the early embryonic death caused by the targeted deletion of the erk5 or the mek5 genes in mice. Here, we have found that ERK5 is required for mediating the survival of fibroblasts under basal conditions and in response to sorbitol treatment. Increased Fas ligand (FasL) expression acts as a positive feedback loop to enhance apoptosis of ERK5- or MEK5-deficient cells under conditions of osmotic stress. Compared to wild-type cells, erk5-/- and mek5-/- fibroblasts treated with sorbitol display a reduced protein kinase B (PKB) activity associated with increased Forkhead box O3a (Foxo3a) activity. Based on these results, we conclude that the ERK5 signaling pathway promotes cell survival by downregulating FasL expression via a mechanism that implicates PKB-dependent inhibition of Foxo3a downstream of phosphoinositide 3 kinase. Show less
In Akita and OVE26 mice, two genetic models of type 1 diabetes, diabetic nephropathy is characterized by mesangial expansion and loss of podocytes, resulting in glomerulosclerosis and proteinuria, and Show more
In Akita and OVE26 mice, two genetic models of type 1 diabetes, diabetic nephropathy is characterized by mesangial expansion and loss of podocytes, resulting in glomerulosclerosis and proteinuria, and is associated with increased expression of profibrotic growth factors, proinflammatory cytokines, and increased oxidative stress. We have also found significant increases in renal triglyceride and cholesterol content. The increase in renal triglyceride content is associated with 1) increased expression of sterol regulatory element-binding protein (SREBP)-1c and carbohydrate response element-binding protein (ChREBP), which collectively results in increased fatty acid synthesis, 2) decreased expression of peroxisome proliferator-activated receptor (PPAR)-alpha and -delta, which results in decreased fatty acid oxidation, and 3) decreased expression of farnesoid X receptor (FXR) and small heterodimer partner (SHP). The increase in cholesterol content is associated with 1) increased expression of SREBP-2 and 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase, which results in increased cholesterol synthesis, and 2) decreased expression of liver X receptor (LXR)-alpha, LXR-beta, and ATP-binding cassette transporter-1, which results in decreased cholesterol efflux. Our results indicate that in type 1 diabetes, there is altered renal lipid metabolism favoring net accumulation of triglycerides and cholesterol, which are driven by increases in SREBP-1, ChREBP, and SREBP-2 and decreases in FXR, LXR-alpha, and LXR-beta, which may also play a role in the increased expression of profibrotic growth hormones, proinflammatory cytokines, and oxidative stress. Show less
Fatty acid elongases and desaturases play an important role in hepatic and whole body lipid composition. We examined the role that key transcription factors played in the control of hepatic elongase a Show more
Fatty acid elongases and desaturases play an important role in hepatic and whole body lipid composition. We examined the role that key transcription factors played in the control of hepatic elongase and desaturase expression. Studies with peroxisome proliferator-activated receptor alpha (PPARalpha)-deficient mice establish that PPARalpha was required for WY14643-mediated induction of fatty acid elongase-5 (Elovl-5), Elovl-6, and all three desaturases [Delta(5) desaturase (Delta(5)D), Delta(6)D, and Delta(9)D]. Increased nuclear sterol-regulatory element binding protein-1 (SREBP-1) correlated with enhanced expression of Elovl-6, Delta(5)D, Delta(6)D, and Delta(9)D. Only Delta(9)D was also regulated independently by liver X receptor (LXR) agonist. Glucose induction of l-type pyruvate kinase, Delta(9)D, and Elovl-6 expression required the carbohydrate-regulatory element binding protein/MAX-like factor X (ChREBP/MLX) heterodimer. Suppression of Elovl-6 and Delta(9)D expression in livers of streptozotocin-induced diabetic rats and high fat-fed glucose-intolerant mice correlated with low levels of nuclear SREBP-1. In leptin-deficient obese mice (Lep(ob/ob)), increased SREBP-1 and MLX nuclear content correlated with the induction of Elovl-5, Elovl-6, and Delta(9)D expression and the massive accumulation of monounsaturated fatty acids (18:1,n-7 and 18:1,n-9) in neutral lipids. Diabetes- and obesity-induced changes in hepatic lipid composition correlated with changes in elongase and desaturase expression. In conclusion, these studies establish a role for PPARalpha, LXR, SREBP-1, ChREBP, and MLX in the control of hepatic fatty acid elongase and desaturase expression and lipid composition. Show less
To detect the disease-causing gene mutation of hypertrophic cardiomyopathy (HCM) in a Chinese family and to analyze the correlation of the genotype and the phenotype. One family affected with HCM was Show more
To detect the disease-causing gene mutation of hypertrophic cardiomyopathy (HCM) in a Chinese family and to analyze the correlation of the genotype and the phenotype. One family affected with HCM was studied. The clinical data including symptom, physical examination, echocardiography and electrocardiography were collected. The full encoding exons and flanking sequences of beta-myosin heavy chain gene (MYH7) and cardiac myosin-binding protein C gene (MYBPC3) were amplified with PCR and the products were sequenced. A G8887A mutation, which is an acceptor splicing site of intron 15 (IVS15-1G > A) in MYBPC3 (gi: Y10129) was identified in 6 out of 11 family members. Three mutation carriers developed HCM at 48 - 75 years old with mild chest pain, chest distress and asymmetric septal hypertrophy (13 - 14 mm) and remaining mutation carriers are free of HCM. No mutation was identified in MYH7 gene. HCM caused by the IVS15-1G > A mutation is a benign phenotype. It is helpful to screen MYBPC3 gene mutation in late-onset HCM patients with mild symptoms. Show less
The recently discovered apolipoprotein A5 ( APOA5 ) gene has been shown to be important in determining plasma triglyceride levels, a major cardiovascular disease risk factor. We searched for possible Show more
The recently discovered apolipoprotein A5 ( APOA5 ) gene has been shown to be important in determining plasma triglyceride levels, a major cardiovascular disease risk factor. We searched for possible associations of the APOA5 gene polymorphisms S19W and -1131T>C with coronary heart disease (CHD) in a Chinese population. A total of 483 Chinese CHD patients and 502 control non-CHD subjects were genotyped by polymerase chain reaction-restriction fragment length polymorphism for these 2 single nucleotide polymorphisms. We found that the minor allele 19W was observed only in CHD patients and not in controls, with allelic frequencies of 0.047 and 0.000, respectively ( P < .000001), and the minor allele -1131C was significantly higher in CHD patients than in controls (0.391 vs 0.299, P < .0001). These results suggest that both the S19W and -1131T>C variations in the APOA5 gene are associated with the CHD and appear to be 2 genetic risk factors for CHD susceptibility in Chinese. Moreover, we found that triglyceride levels were significantly higher in -1131C carriers than in -1131T subjects of the control group and that high-density-lipoprotein cholesterol was decreased in -1131C carriers among CHD patients. Show less
Triglyceride-rich lipoprotein particles may promote the progression of diabetic nephropathy. Patients with diabetic nephropathy have increased plasma triglycerides and reduced activity of hepatic lipa Show more
Triglyceride-rich lipoprotein particles may promote the progression of diabetic nephropathy. Patients with diabetic nephropathy have increased plasma triglycerides and reduced activity of hepatic lipase (HL), which hydrolyzes triglycerides. We hypothesized that the HL -514C-->T polymorphism, which reduces HL expression, and its interactions with polymorphisms in apolipoprotein (apo) E and apoC3 increase the risk of diabetic nephropathy. In a case-control study involving 374 Chinese type 2 diabetic patients with and 392 without diabetic nephropathy, we genotyped the HL -514C-->T, apoE exon 4, and apoC3 -482C-->T polymorphisms. HL -514T-containing genotypes (T+) were associated with diabetic nephropathy (OR = 1.7, P = 0.0009). Adjustment by multiple logistic regression for hypertension, triglycerides, sex, non-HDL cholesterol, BMI, smoking, and alcohol intake did not diminish the association (OR = 1.8, P = 0.003). The association between HL T+ genotypes and diabetic nephropathy appeared stronger in diabetic patients with apoC3 -482 non-TT genotypes (OR = 1.9, P = 0.003) or apoE epsilon2 or epsilon4 alleles (OR = 2.2, P = 0.005). Subjects with HL TT exhibited trends toward increased triglyceride and non-HDL cholesterol levels compared with CC carriers. HL T+ genotypes might increase the risk of developing diabetic nephropathy by slowing clearance of triglyceride-rich remnant lipoproteins. In concert with other risk factors (e.g., hyperglycemia), lipid abnormalities may damage the kidneys and endothelium, where reduced binding sites for lipases may precipitate a vicious cycle of dyslipidemia, proteinuria, and nephropathy. Show less