Xuefeng Li, Yancheng Xu, Yan Ding+3 more · 2008 · Journal of Huazhong University of Science and Technology. Medical sciences = Hua zhong ke ji da xue xue bao. Yi xue Ying De wen ban = Huazhong keji daxue xuebao. Yixue Yingdewen ban · Springer · added 2026-04-24
This study investigated the association of apolipoprotein A5 (apoA5) gene polymorphism at position -1131T>C with cerebral infarction in patients with type 2 diabetes. A total of 256 type 2 diabetic pa Show more
This study investigated the association of apolipoprotein A5 (apoA5) gene polymorphism at position -1131T>C with cerebral infarction in patients with type 2 diabetes. A total of 256 type 2 diabetic patients without cerebral infarction (T2DM), 220 type 2 diabetic patients with cerebral infarction (T2DMCI) and 340 healthy subjects were recruited from the same region (Hubei province, China). The genotype of apoA5 -1131T[Symbol: see text]C was analyzed by polymerase chain reaction, followed by restriction fragment length polymorphism (PCR-RFLP). Total cholesterol, HDL cholesterol, LDL-cholesterol and triglycerides were quantitatively detected by using standard enzymatic techniques. The results showed that the prevalence of the apoA5 -1131C allele was significantly higher in T2DMCI group than that in control group (42.7% versus 31.2%, P<0.01). The carriers of rare C allele had higher TG levels as compared with carriers of common allele in the three groups (P<0.01). Logistic regression models, which were adjusted for age, gender, blood pressure, BMI, FBS, smoking, LDL-C and HDL-C, revealed that patients carrying the apoA5 -1131C allele and CC homozygotes were at high risk for T2DMCI. It was concluded that the apoA5 -1131C allele variant is an independent genetic risk factor for T2DMCI. Show less
Kui Zhang, Fang Qiu, Lei Li+5 more · 2008 · Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics · added 2026-04-24
To investigate the association of -1131T>C and c.553G>T polymorphisms and their haplotypes in apolipoprotein A5(ApoA5) gene with cereberovascular disease in Chinese. Using polymerase chain reaction-re Show more
To investigate the association of -1131T>C and c.553G>T polymorphisms and their haplotypes in apolipoprotein A5(ApoA5) gene with cereberovascular disease in Chinese. Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), we analyzed two ApoA5 genetic variants in 272 patients with cerebral infarction (CI) and 316 control individuals respectively. The levels of serum lipid profiles were measured with biochemical methodsìand the other clinical characters were obtained by case file investigation. The odds ratio (OR) for CI in -1131CC genotype carriers was 2.10 (95%CI 1.01-4.37). The distribution of T-T and T-G haplotypes had obvious differences between CI patients and control individuals. The OR for CI in C-G and T-G haplotype carriers were 1.34 and 0.71(95% CI 1.02-1.76 and 0.55-0.92) respectively, compared with the others. Furthermore, the major haplotypes had significant differences of serum TG(P< 0.05). The ApoA5 -1131T>C polymorphism may be associated with an increased risk of CI in the Chinese population, but the influence of blood lipids can not be ignored. Show less
Intermittent administration of PTH stimulates bone formation, but the precise mechanisms responsible for PTH responses in osteoblasts are only incompletely understood. Here we show that binding of PTH Show more
Intermittent administration of PTH stimulates bone formation, but the precise mechanisms responsible for PTH responses in osteoblasts are only incompletely understood. Here we show that binding of PTH to its receptor PTH1R induced association of LRP6, a coreceptor of Wnt, with PTH1R. The formation of the ternary complex containing PTH, PTH1R, and LRP6 promoted rapid phosphorylation of LRP6, which resulted in the recruitment of axin to LRP6, and stabilization of beta-catenin. Activation of PKA is essential for PTH-induced beta-catenin stabilization, but not for Wnt signaling. In vivo studies confirmed that PTH treatment led to phosphorylation of LRP6 and an increase in amount of beta-catenin in osteoblasts with a concurrent increase in bone formation in rat. Thus, LRP6 coreceptor is a key element of the PTH signaling that regulates osteoblast activity. Show less
MIP-T3 is a human protein found previously to associate with microtubules and the kinesin-interacting neuronal protein DISC1 (Disrupted-in-Schizophrenia 1), but whose cellular function(s) remains unkn Show more
MIP-T3 is a human protein found previously to associate with microtubules and the kinesin-interacting neuronal protein DISC1 (Disrupted-in-Schizophrenia 1), but whose cellular function(s) remains unknown. Here we demonstrate that the C. elegans MIP-T3 ortholog DYF-11 is an intraflagellar transport (IFT) protein that plays a critical role in assembling functional kinesin motor-IFT particle complexes. We have cloned a loss of function dyf-11 mutant in which several key components of the IFT machinery, including Kinesin-II, as well as IFT subcomplex A and B proteins, fail to enter ciliary axonemes and/or mislocalize, resulting in compromised ciliary structures and sensory functions, and abnormal lipid accumulation. Analyses in different mutant backgrounds further suggest that DYF-11 functions as a novel component of IFT subcomplex B. Consistent with an evolutionarily conserved cilia-associated role, mammalian MIP-T3 localizes to basal bodies and cilia, and zebrafish mipt3 functions synergistically with the Bardet-Biedl syndrome protein Bbs4 to ensure proper gastrulation, a key cilium- and basal body-dependent developmental process. Our findings therefore implicate MIP-T3 in a previously unknown but critical role in cilium biogenesis and further highlight the emerging role of this organelle in vertebrate development. Show less
Biao Luo, Hiu Wing Cheung, Aravind Subramanian+21 more · 2008 · Proceedings of the National Academy of Sciences of the United States of America · National Academy of Sciences · added 2026-04-24
More complete knowledge of the molecular mechanisms underlying cancer will improve prevention, diagnosis and treatment. Efforts such as The Cancer Genome Atlas are systematically characterizing the st Show more
More complete knowledge of the molecular mechanisms underlying cancer will improve prevention, diagnosis and treatment. Efforts such as The Cancer Genome Atlas are systematically characterizing the structural basis of cancer, by identifying the genomic mutations associated with each cancer type. A powerful complementary approach is to systematically characterize the functional basis of cancer, by identifying the genes essential for growth and related phenotypes in different cancer cells. Such information would be particularly valuable for identifying potential drug targets. Here, we report the development of an efficient, robust approach to perform genome-scale pooled shRNA screens for both positive and negative selection and its application to systematically identify cell essential genes in 12 cancer cell lines. By integrating these functional data with comprehensive genetic analyses of primary human tumors, we identified known and putative oncogenes such as EGFR, KRAS, MYC, BCR-ABL, MYB, CRKL, and CDK4 that are essential for cancer cell proliferation and also altered in human cancers. We further used this approach to identify genes involved in the response of cancer cells to tumoricidal agents and found 4 genes required for the response of CML cells to imatinib treatment: PTPN1, NF1, SMARCB1, and SMARCE1, and 5 regulators of the response to FAS activation, FAS, FADD, CASP8, ARID1A and CBX1. Broad application of this highly parallel genetic screening strategy will not only facilitate the rapid identification of genes that drive the malignant state and its response to therapeutics but will also enable the discovery of genes that participate in any biological process. Show less
Histone deacetylase inhibitor (HDACi) has been shown to demethylate the mammalian genome, which further strengthens the concept that DNA methylation and histone modifications interact in regulation of Show more
Histone deacetylase inhibitor (HDACi) has been shown to demethylate the mammalian genome, which further strengthens the concept that DNA methylation and histone modifications interact in regulation of gene expression. Here, we report that an HDAC inhibitor, depsipeptide, exhibited significant demethylating activity on the promoters of several genes, including p16, SALL3, and GATA4 in human lung cancer cell lines H719 and H23, colon cancer cell line HT-29, and pancreatic cancer cell line PANC1. Although expression of DNA methyltransferase 1 (DNMT1) was not affected by depsipeptide, a decrease in binding of DNMT1 to the promoter of these genes played a dominant role in depsipeptide-induced demethylation and reactivation. Depsipeptide also suppressed expression of histone methyltransferases G9A and SUV39H1, which in turn resulted in a decrease of di- and trimethylated H3K9 around these genes' promoter. Furthermore, both loading of heterochromatin-associated protein 1 (HP1alpha and HP1beta) to methylated H3K9 and binding of DNMT1 to these genes' promoter were significantly reduced in depsipeptide-treated cells. Similar DNA demethylation was induced by another HDAC inhibitor, apicidin, but not by trichostatin A. Our data describe a novel mechanism of HDACi-mediated DNA demethylation via suppression of histone methyltransferases and reduced recruitment of HP1 and DNMT1 to the genes' promoter. Show less
Lisa D Urness, Chaoying Li, Xiaofen Wang+1 more · 2008 · Developmental dynamics : an official publication of the American Association of Anatomists · Wiley · added 2026-04-24
The levels of fibroblast growth factor (FGF) signaling play important roles in coordinating development of the mouse inner, middle, and outer ears. Extracellular signal-regulated kinases (ERKs) are am Show more
The levels of fibroblast growth factor (FGF) signaling play important roles in coordinating development of the mouse inner, middle, and outer ears. Extracellular signal-regulated kinases (ERKs) are among the effectors that transduce the FGF signal to the nucleus and other cellular compartments. Attenuation of ERK activity by dephosphorylation is necessary to modulate the magnitude and duration of the FGF signal. Recently, we showed that inactivation of the ERK phosphatase, dual specificity phosphatase 6 (DUSP6), causes partially penetrant postnatal lethality, hearing loss and skeletal malformations. To determine whether other Dusps may function redundantly with Dusp6 during otic development, we surveyed the expression domains of the three ERK-specific DUSP transcripts, Dusp6, Dusp7, and Dusp9, in the embryonic mouse ear. We show that each is expressed in partially overlapping patterns that correspond to regions of active FGF signaling, suggesting combinatorial roles in negative regulation of this pathway during ear development. Show less
Previous studies showed that expression of the novel candidate tumor suppressor gene, DEC1 (Deleted in Esophageal Cancer 1), is reduced in esophageal carcinoma and suppresses cancer cell growth in vit Show more
Previous studies showed that expression of the novel candidate tumor suppressor gene, DEC1 (Deleted in Esophageal Cancer 1), is reduced in esophageal carcinoma and suppresses cancer cell growth in vitro and tumor growth in vivo in nude mice. This study shows that DEC1 gene expression was downregulated in 100% of 16 esophageal squamous cell carcinoma (ESCC) cell lines and 52 and 45%, respectively, of esophageal tumor specimens from Hong Kong and a high-risk ESCC region of Henan, China. Using epitope tagging, the DEC1 protein was localized to both the cytoplasm and nucleus of the cell. In 3D Matrigel culture, no significant difference in colony numbers formed was observed for DEC1 stable transfectants, as compared to vector-alone transfectant controls. However, significantly smaller colony sizes were observed for the DEC1 transfectants. In in vitro cell migration, invasion and soft agar assays of DEC1 transfectants, only the soft agar assay showed statistically significant differences in colony numbers with the vector-alone controls, indicating that DEC1 may be involved in anchorage-independent cell growth. In addition, the global gene expression affected by DEC1 in tumor-suppressive stable transfectants was investigated using cDNA oligonucleotide microarray hybridization. Three candidate genes, TFPI-2, GDF15 and DUSP6, were identified through this approach; they are downregulated in tumor segregants of DEC1 stable transfectants, ESCC cell lines and esophageal tumors and have a potential role in tumor growth and progression. These studies show that DEC1 is involved in esophageal cancer development and help elucidate its functional role in tumor development. Show less
During mouse development, the precursor cells that give rise to the auditory sensory organ, the organ of Corti, are specified prior to embryonic day 14.5 (E14.5). Subsequently, the sensory domain is p Show more
During mouse development, the precursor cells that give rise to the auditory sensory organ, the organ of Corti, are specified prior to embryonic day 14.5 (E14.5). Subsequently, the sensory domain is patterned precisely into one row of inner and three rows of outer sensory hair cells interdigitated with supporting cells. Both the restriction of the sensory domain and the patterning of the sensory mosaic of the organ of Corti involve Notch-mediated lateral inhibition and cellular rearrangement characteristic of convergent extension. This study explores the expression and function of a putative Notch target gene. We report that a putative Notch target gene, hairy-related basic helix-loop-helix (bHLH) transcriptional factor Hey2, is expressed in the cochlear epithelium prior to terminal differentiation. Its expression is subsequently restricted to supporting cells, overlapping with the expression domains of two known Notch target genes, Hairy and enhancer of split homolog genes Hes1 and Hes5. In combination with the loss of Hes1 or Hes5, genetic inactivation of Hey2 leads to increased numbers of mis-patterned inner or outer hair cells, respectively. Surprisingly, the ectopic hair cells in Hey2 mutants are accompanied by ectopic supporting cells. Furthermore, Hey2-/-;Hes1-/- and Hey2-/-;Hes1+/- mutants show a complete penetrance of early embryonic lethality. Our results indicate that Hey2 functions in parallel with Hes1 and Hes5 in patterning the organ of Corti, and interacts genetically with Hes1 for early embryonic development and survival. Our data implicates expansion of the progenitor pool and/or the boundaries of the developing sensory organ to account for patterning defects observed in Hey2 mutants. Show less
Plasma liver-enzyme tests are widely used in the clinic for the diagnosis of liver diseases and for monitoring the response to drug treatment. There is considerable evidence that human genetic variati Show more
Plasma liver-enzyme tests are widely used in the clinic for the diagnosis of liver diseases and for monitoring the response to drug treatment. There is considerable evidence that human genetic variation influences plasma levels of liver enzymes. However, such genetic variation has not been systematically assessed. In the present study, we performed a genome-wide association study of plasma liver-enzyme levels in three populations (total n = 7715) with replication in three additional cohorts (total n = 4704). We identified two loci influencing plasma levels of alanine-aminotransferase (ALT) (CPN1-ERLIN1-CHUK on chromosome 10 and PNPLA3-SAMM50 on chromosome 22), one locus influencing gamma-glutamyl transferase (GGT) levels (HNF1A on chromosome 12), and three loci for alkaline phosphatase (ALP) levels (ALPL on chromosome 1, GPLD1 on chromosome 6, and JMJD1C-REEP3 on chromosome 10). In addition, we confirmed the associations between the GGT1 locus and GGT levels and between the ABO locus and ALP levels. None of the ALP-associated SNPs were associated with other liver tests, suggesting intestine and/or bone specificity. The mechanisms underlying the associations may involve cis- or trans-transcriptional effects (some of the identified variants were associated with mRNA transcription in human liver or lymphoblastoid cells), dysfunction of the encoded proteins (caused by missense variations at the functional domains), or other unknown pathways. These findings may help in the interpretation of liver-enzyme tests and provide candidate genes for liver diseases of viral, metabolic, autoimmune, or toxic origin. The specific associations with ALP levels may point to genes for bone or intestinal diseases. Show less
As a model for both multistep and multipathway carcinogenesis, colorectal neoplastic progression provides paradigms for researching both oncogenes and tumor suppressor genes (TSGs). However, the mecha Show more
As a model for both multistep and multipathway carcinogenesis, colorectal neoplastic progression provides paradigms for researching both oncogenes and tumor suppressor genes (TSGs). However, the mechanism of colorectal cancer (CRC) is not completely understood, and many genes may be involved in the colorectal carcinogenesis. The purpose of this study was to screen for the potential TSGs on chromosome 1q31.1-32.1 in Chinese patients with sporadic colorectal cancer, to explore whether colorectal cancer in the Chinese population has unique genetic alterations and determine whether other putative TSGs exist and contribute to colon carcinogenesis. Six polymorphic microsatellite markers, at a density of approximately one marker in every 1.6 cM, were chosen for refined loss of heterozygosity (LOH) mapping of 1q31.1-32.1. Eighty-three colorectal cancer patients' tumor and normal DNA were analyzed via polymerase chain reaction (PCR) for these microsatellite markers. PCR products were eletrophoresed on an ABI 377 DNA sequencer. Genescan 3.1 and Genotype 2.1 software were used for LOH scanning and analysis. On the basis of refined LOH mapping results, we undertook a microarray-based expression screening to identify tumor association genes in 19 of the CRC cases. The average LOH frequency of 1q31.1-32.1 was 24.41%, with the highest frequency of 36.73% (18/49) at D1S2622, and the lowest of 16.42% (11/67) at D1S412. A minimal region of frequent deletion was located within a 2 cM genomic segment at D1S413-D1S2622. There was no significant association between LOH of any marker in the studied regions and the clinicopathological data (patient sex, age, tumor size, growth pattern, or Dukes stage). On the basis of refined mapping results, we chose 25 genes located in the D1S413-D1S2622 (1q31.3-32.1) region and presented a microarray-based high throughput screening approach in 19 sporadic CRC cases to identify candidate CRC related tumor suppressor genes. This study found 4 significantly down-expressed genes, including CSRP1, LMOD1, PPP1R12B and CFHL3. There was no significant association between expression levels of CFHL3, CSRP1, LMOD1, PPP1R12B and the clinicopathological data. By database searching, CSRP1 was hypothesized to be a colorectal cancer related tumor suppressor gene. Through detailed deletion mapping, we found that the 1q31.3-32.1 region might harbor one or more colorectal cancer related tumor suppressor gene (s). And by microarray-based high-throughput screening of candidate genes located in this region and by subsequent database searching, we present the first evidence that CSRP1 might be involved in the progression of CRC. Show less
Carbohydrate response element-binding protein (ChREBP) is a basic helix-loop-helix/leucine zipper transcription factor that binds to the carbohydrate response element in the promoter of certain lipoge Show more
Carbohydrate response element-binding protein (ChREBP) is a basic helix-loop-helix/leucine zipper transcription factor that binds to the carbohydrate response element in the promoter of certain lipogenic and glycolytic genes. High glucose can activate ChREBP by releasing an intramolecular inhibition within the glucose-sensing module (GSM) that occurs in low glucose. We report here that the glucose response of GSM is mediated by cooperation between five conserved submodules known as Mondo conserved regions (MCRs) I through V within GSM. Deletion of individual MCRs leads to complete (for MCR II, III, and IV) or partial (MCR I) loss of glucose response of ChREBP. MCR IV is necessary and sufficient for inhibiting the transcriptional activity of ChREBP under low glucose. The roles of MCR II and III in glucose response of ChREBP are independent of and distinct from their function in controlling subcellular localization. We further demonstrate that, instead of inhibiting ChREBP activity as would be predicted from its cytoplasmic retentive function, 14-3-3 binding with MCR III is essential for the glucose responsiveness of ChREBP. The interaction between 14-3-3 and ChREBP is constitutive, indicating a permissive role of 14-3-3 in the glucose response of ChREBP. We further uncovered an unconventional 14-3-3 binding motif (residues 116-135) lacking phosphor-serine/threonine within MCR III, a predicted alpha-helix highly conserved in all Mondo proteins. We conclude that individual subdomains in the GSM (MCR I through V) play diverse but crucial roles in cooperation with essential trans-acting cofactors such as 14-3-3 proteins to mediate the glucose response of ChREBP. Show less
Liver X receptor (LXR) is known to promote hepatic lipogenesis by activating the lipogenic transcriptional factor sterol regulatory element-binding protein (Srebp). Pregnane X receptor (PXR), a previo Show more
Liver X receptor (LXR) is known to promote hepatic lipogenesis by activating the lipogenic transcriptional factor sterol regulatory element-binding protein (Srebp). Pregnane X receptor (PXR), a previously known "xenobiotic receptor," could mediate a Srebp-independent lipogenic pathway by activating the free fatty acid uptake transporter Cd36. The goal of this study is to investigate further the role of Cd36 in hepatic steatosis. Wild-type, LXR transgenic, PXR transgenic, and Cd36 null mice were used to study the regulation of Cd36 and other hepatic lipogenic genes and the implication of this regulation in hepatic steatosis. Promoter sequences of Cd36 and peroxisome proliferator-activated receptor (PPAR) gamma were cloned, and their respective regulation by LXR and PXR was investigated by combinations of receptor-DNA binding and reporter gene assays. We showed that genetic (transgene) or pharmacologic (ligands) activation of LXR induced Cd36. Promoter analysis established Cd36 as a novel transcription target of LXRalpha. Moreover, the hepatic steatosis induced by LXR agonists was largely abolished in Cd36 null mice. We also showed that PPARgamma, a positive regulator of Cd36, is a transcriptional target of PXR, suggesting that PXR can regulate Cd36 directly or through its activation of PPARgamma. Interestingly, both LXR-mediated Cd36 regulation and PXR-mediated PPARgamma regulation are liver specific. We conclude that Cd36 is a shared target of LXR, PXR, and PPARgamma. The network of CD36 regulation by LXR, PXR, and PPARgamma establishes this free fatty acid transporter as a common target of orphan nuclear receptors in their mediation of lipid homeostasis. Show less
The PIK3C3 gene has been implicated as a candidate gene for schizophrenia by functional evidence and genetic association studies. A series of previous studies have found susceptibility SNPs in promote Show more
The PIK3C3 gene has been implicated as a candidate gene for schizophrenia by functional evidence and genetic association studies. A series of previous studies have found susceptibility SNPs in promoter region. To further verify its susceptibility to schizophrenia in the Chinese population and the function of the polymorphisms, we performed a case control study in 556 unrelated schizophrenia patients and 563 normal controls as well as an in vitro functional analysis. In our association analysis of-432C-/T, we discovered obvious differences in allele frequency between patients and controls (P=0.017). A T/C haplotype constructed by -432C-/T and -86insC, which are tightly linked with each other (r(2)=1) can significantly weaken promoter's transcriptional activity by 20% (p=0.002 by t-test). Though we cannot exclude the possibility that susceptibility of -432C-/T is caused by its linkage disequilibrium with other causal variants, our results do support PIK3C3 play a significant role in the etiology of schizophrenia. Show less
Voltage-gated cation channels regulate neuronal excitability through selective ion flux. NALCN, a member of a protein family that is structurally related to the alpha1 subunits of voltage-gated sodium Show more
Voltage-gated cation channels regulate neuronal excitability through selective ion flux. NALCN, a member of a protein family that is structurally related to the alpha1 subunits of voltage-gated sodium/calcium channels, was recently shown to regulate the resting membrane potentials by mediating sodium leak and the firing of mouse neurons. We identified a role for the Caenorhabditis elegans NALCN homologues NCA-1 and NCA-2 in the propagation of neuronal activity from cell bodies to synapses. Loss of NCA activities leads to reduced synaptic transmission at neuromuscular junctions and frequent halting in locomotion. In vivo calcium imaging experiments further indicate that while calcium influx in the cell bodies of egg-laying motorneurons is unaffected by altered NCA activity, synaptic calcium transients are significantly reduced in nca loss-of-function mutants and increased in nca gain-of-function mutants. NCA-1 localizes along axons and is enriched at nonsynaptic regions. Its localization and function depend on UNC-79, and UNC-80, a novel conserved protein that is also enriched at nonsynaptic regions. We propose that NCA-1 and UNC-80 regulate neuronal activity at least in part by transmitting depolarization signals to synapses in C. elegans neurons. Show less
Glucose-dependent insulinotropic polypeptide (GIP) stimulates insulin release via interaction with its pancreatic receptor (GIP receptor (GIPR)). GIP also acts as vasoactive protein. To investigate wh Show more
Glucose-dependent insulinotropic polypeptide (GIP) stimulates insulin release via interaction with its pancreatic receptor (GIP receptor (GIPR)). GIP also acts as vasoactive protein. To investigate whether variations in GIP and GIPR genes are associated with risk factors of the metabolic syndrome we sequenced gene regions and identified two coding SNPs (GIP Ser103Gly, GIPR Glu354Gln) and one splice site SNP (GIP rs2291726) in 47 subjects. Interestingly, in silico analyses revealed that splice site SNP rs2291726 results in a truncated protein and classified GIPR variant Glu354Gln as a functional amino acid change. Association analyses were performed in a case-cohort study of incident cardiovascular disease (CVD) nested in the EPIC-Potsdam cohort. No significant associations between incident CVD and GIP Ser103Gly and rs2291726 were found. For GIPR Glu354Gln, we obtained a nominal association of heterozygous minor allele carrier with CVD in a codominant model adjusted for BMI, sex, and age (OR: 0.67, CI: 0.50-0.91, p = 0.01) or additional covariates of CVD (OR: 0.72, CI: 0.52-0.97, p = 0.03). In conclusion, we identified a common splice site mutation (rs2291726) of the GIP gene which results in a truncated protein and provide preliminary evidence for an association of the heterozygous GIPR Glu354Gln genotype with CVD. Show less
To explore the relationship between the expression characteristics of lipid metabolism-related genes in the liver and early atherosclerotic lesions in apolipoprotein E and low density lipoprotein rece Show more
To explore the relationship between the expression characteristics of lipid metabolism-related genes in the liver and early atherosclerotic lesions in apolipoprotein E and low density lipoprotein receptor gene double knockout (apoE(-/-)/LDLR(-/-)) mice. RT-PCR was used to detect the differential expression of lipid metabolism-related genes in the liver of apoE(-/-)/LDLR(-/-) and wild type (WT) mice. Serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) level as well as aortic morphology were also analyzed. Among the 11 lipid metabolism-related genes, apolipoprotein B100 (apoB100) mRNA levels were significantly higher in apoE(-/-)/LDLR(-/-)mice compared with WT mice. At 14 days, 1, 2 and 3 months of age, the level of mRNA expression were 1.55, 1.47, 1.50 and 2.42 folds of those of the age matched WT mice respectively. The fatty acid transporter (FAT/CD36) mRNA expression levels were higher in 14-day and 3-month old mice at 1.30 and 1.35 folds of those of the age matched WT mice, respectively. Apolipoprotein A IV (apoA IV) and Apolipoprotein AV (apoAV) mRNA levels were significantly down-regulated (0.89 fold decrease in 14-day, and 0.90 folds decrease in 3-month, respectively). The mRNA expression levels of apolipoprotein AI (apo AI), apolipoprotein F (apo F), peroxidase proliferator-activated receptor alpha (PPAR-alpha), liver X receptor alpha (LXRalpha), angiopoietin-like protein 3 (ANGPTL3), acyl-coenzymeA oxidase 1 (ACOX1) and carnitine palmitoyl transferase 1 (CPT1) had no significant changes. Serum TC, TG and LDL-C were higher than those of age matched WT mice at 7, 2 and 30 folds, respectively. Furthermore, apoE(-/-)/LDLR(-/-) mice demonstrated typical early atherosclerotic lesions at sinus and root regions of aorta in an age dependent manner. Alterations of the expression of lipid metabolism-related genes in liver play important roles in the development of AS in the apoE(-/-)/LDLR(-/-) mice at early ages. Show less
To investigate the changes of several protein markers in a metastatic colorectal carcinoma model by serum proteomic analysis. The pEGFP-N1 plasmid with enhanced expression of green fluorescence protei Show more
To investigate the changes of several protein markers in a metastatic colorectal carcinoma model by serum proteomic analysis. The pEGFP-N1 plasmid with enhanced expression of green fluorescence protein (EGFP) was transfected into human colon carcinoma cell line SW480 to obtain a stable SW480-EGFP cell line, the SW480-EGFP cells were then injected subcutaneously into nude mice. The harvested tumor cells were implanted orthotopically into the colon of the nude mice. Real-time tumor growth and metastasis formation were visualized by whole-body fluorescent imaging system. Serum samples at different metastatic stages were collected and differential proteomic profiles were investigated by two-dimensional gel electrophoresis (2DE) and matrix-assisted laser absorption/ionization time of flight mass spectrometry (MALDI-TOF MS). The SW480- EGFP cells enabled to express EGFP stably. The rates of subcutaneous and orthotropic tumor formation were 100%. The metastasis rates to local lymph nodes, liver and lung were 100%, 40% and 30%, respectively. Furthermore, 5 differentially expressed proteins were analyzed by serum proteome technologies, including haptoglobin alpha chain, apolipoprotein E, apolipoprotein A-IV, Ig kappa chain V region chain L and transferrin. Visualized metastatic model of colorectal carcinoma was successfully established. Several differentially expressed serum proteins collected at different stages after the occurrence of metastasis were identified. These differentially expressed proteins may be candidate serum biomarkers for diagnosis and therapeutic evaluation of colorectal carcinoma metastasis. Show less
Jie Li, Hong-wei Xu, Xiao-yan Zhu · 2007 · Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics · added 2026-04-24
To investigate the relationship between the polymorphism of apolipoprotein A5 gene (APOA5) -12238 T>C and atherosclerotic cerebral infarction (ACI). Three hundred and forty-one subjects (170 ACI patie Show more
To investigate the relationship between the polymorphism of apolipoprotein A5 gene (APOA5) -12238 T>C and atherosclerotic cerebral infarction (ACI). Three hundred and forty-one subjects (170 ACI patients and 171 healthy controls) were collected to determine the genotypes by using polymerase chain reaction-restriction fragment length polymorphisms. APOA5 allele frequencies of T/C were 0.588/0.412 and 0.424/0.576 in ACI group and control group respectively. There was significant difference in allele and genotype frequencies between ACI group and control group (P < 0.05). The levels of plasma triglyceride in ACI patients with TT genotype were higher than those in patients with CC genotypes (P < 0.05). The relationship is found between the site of APOA5 gene -12238 T>C and ACI. There is a significant correlation between TT genotype of APOA5 and the levels of plasma triglyceride in patients with ACI. Show less
Apolipoprotein A5 (ApoA5) is present in human serum at a very low concentration. We developed a new method to determine ApoA5 concentration in human serum, and to investigate the correlation between s Show more
Apolipoprotein A5 (ApoA5) is present in human serum at a very low concentration. We developed a new method to determine ApoA5 concentration in human serum, and to investigate the correlation between serum ApoA5 and the lipid profiles in healthy subjects, and to analyze whether the correlation was affected by gender. All the subjects (total 92, male 50, female 42) were healthy subjects without any medication. Lipids were measured enzymatically. An ELISA performed by a couple of monoclonal antibodies was used to measure serum ApoA5. The average ApoA5 concentration was 182.7+/-104.7 ng/ml ranging from 5.4 to 455.6 ng/ml. Serum ApoA5 concentration was negatively correlated with TG in female (r=-0.496, P=0.001). In all subjects, ApoA5 concentration was positively correlated to HDL-C (r=0.453, P<0.001). This correlation was more predominant in female (r=0.617, P<0.001) than in male (r=0.289, P=0.042). ApoA5 concentration was negatively correlated to body mass index (BMI) with more significance in female than in male (r=-0.345, P=0.001 for all; r=-0.456, P=0.002 for female; r=-0.198, P=0.167 for male). The serum concentration of ApoA5 was very low. The concentration of ApoA5 was negatively correlated with TG and BMI, but positively correlated with HDL-C. The correlations were affected by gender. 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
To investigate the association between the configurational and compositional changes of nuclear matrix and the differentiation of carcinoma cells. Cells cultured with or without 5 x 10(-3) mmol/L of h Show more
To investigate the association between the configurational and compositional changes of nuclear matrix and the differentiation of carcinoma cells. Cells cultured with or without 5 x 10(-3) mmol/L of hexamethylene bisacetamide (HMBA) on Nickel grids were treated by selective extraction and prepared for whole mount observation under electron microscopy. The samples were examined under transmission electron microscope. Nuclear matrix proteins were selectively extracted and subjected to subcellular proteomics study. The protein expression patterns were analyzed by PDQuest software. Spots of differentially expressed nuclear matrix proteins were excised and subjected to in situ digestion with trypsin. The peptides were analyzed by matrix-assisted laser-desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Data were submitted for database searching using Mascot tool (www.matrixscience.com). The nuclear matrix (NM) and intermediate filament (IF) in SMMC-7721 hepatocarcinoma cells were found relatively sparse and arranged irregularly. The nuclear lamina was non-uniform, and two kinds of filaments were not tightly connected. After induction for differentiation by HMBA, the NM-IF filaments were concentrated and distributed uniformly. The heterogeneous population of filaments, including highly branched ultrathin filaments could also be seen in the regular meshwork. The connection between the two kinds of filaments and the relatively thin, condensed and sharply demarcated lamina composed of intermediate-sized filaments was relatively fastened. Meanwhile, 21 NM proteins changed remarkably during SMMC-7721 cell differentiation. Four proteins, i.e. mutant Pyst1, hypothetical protein, nucleophosmin 1, and LBP were downregulated, whereas four other proteins, eIF6, p44 subunit, beta-tubulin, and SIN3B were upregulated with the last one, SR2/ASF found only in the differentiated SMMC-7721 cells. The induced differentiation of SMMC-7721 cells by HMBA is accompanied by the configurational changes of nuclear matrix-intermediate filament (NM-IF) system and the compositional changes of nuclear matrix protein expression. These changes may be important morphological or functional indications of the cancer cell reversion. 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
Mitogen-activated protein kinase (MAPK) pathways are major mediators of extracellular signals that are transduced to the nucleus. MAPK signaling is attenuated at several levels, and one class of dual- Show more
Mitogen-activated protein kinase (MAPK) pathways are major mediators of extracellular signals that are transduced to the nucleus. MAPK signaling is attenuated at several levels, and one class of dual-specificity phosphatases, the MAPK phosphatases (MKPs), inhibit MAPK signaling by dephosphorylating activated MAPKs. Several of the MKPs are themselves induced by the signaling pathways they regulate, forming negative feedback loops that attenuate the signals. We show here that in mouse embryos, Fibroblast growth factor receptors (FGFRs) are required for transcription of Dusp6, which encodes MKP3, an extracellular signal-regulated kinase (ERK)-specific MKP. Targeted inactivation of Dusp6 increases levels of phosphorylated ERK, as well as the pERK target, Erm, and transcripts initiated from the Dusp6 promoter itself. Finally, the Dusp6 mutant allele causes variably penetrant, dominant postnatal lethality, skeletal dwarfism, coronal craniosynostosis and hearing loss; phenotypes that are also characteristic of mutations that activate FGFRs inappropriately. Taken together, these results show that DUSP6 serves in vivo as a negative feedback regulator of FGFR signaling and suggest that mutations in DUSP6 or related genes are candidates for causing or modifying unexplained cases of FGFR-like syndromes. Show less
To investigate the effects of 2-methoxyestradiol (2-ME) on 2 myeloid leukemia cell lines HL-60 and U937, and to explore its mechanisms. Human myeloid leukemia cells HL-60 and U937 were used. Measureme Show more
To investigate the effects of 2-methoxyestradiol (2-ME) on 2 myeloid leukemia cell lines HL-60 and U937, and to explore its mechanisms. Human myeloid leukemia cells HL-60 and U937 were used. Measurement of mitochondrial membrane potential (Dym) was performed using 5,5',6,6'-Tetrachloro-1,1',3,3'- tetraethylbenzimidazolylcarbocyanine iodide ( JC-1). Apoptosis and cellular nitric oxide (NO) were detected by flow cytometry using Annexin V and NO sensor dye. Superoxide anion was measured with a fluorescent plate reader by dihydroethidium (DHE). Cytotoxicity was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay. 2-ME resulted in viability decrease in a dose-dependent manner. 2-ME treatment also generated reactive oxygen species (ROS), including NO and superoxide anions, which resulted in mitochondria damage. 2-ME-induced apoptosis was correlated with an increase in ROS. The quenching of ROS with N-acetyl-L-cysteine protected leukemia cells from 2-ME cytotoxicity and prevented apoptosis induction by 2-ME. Furthermore, the addition of manumycin, a farnesyltransferase inhibitor, significantly enhanced apoptosis induced by 2-ME. Cellular ROS generation plays an important role in the cytotoxic effect of 2-ME. It is possible to use ROS generation agents, such as manumycin, to enhance the antileukemic effect. The combination strategy needs further in vivo justification and may have potential clinical application. Show less
Meng Zhang, Shi-guo Liu, Fei-feng Li+3 more · 2007 · Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics · added 2026-04-24
To develop a new denaturing high performance liquid chromatograph (DHPLC)-based method to screen patients with EXT gene mutation and to study the gene mutation in three families with multiple exostose Show more
To develop a new denaturing high performance liquid chromatograph (DHPLC)-based method to screen patients with EXT gene mutation and to study the gene mutation in three families with multiple exostoses. All the exons of EXT gene, including the intro-exon boundaries, were amplified by PCR. Linkage analysis and DHPLC screening were carried out to identify the mutations. DNA sequencing was used to confirm the mutations. Two known splice site mutations, IVS2+1 G to A and IVS7+1 G to T, and two SNPs have been detected in EXT2 or EXT1 gene. The transversions of IVS2+1 G to A and IVS7+1 G to T in EXT2 gene are suggested to be the disease-causing mutations and the DHPLC is a high throughout, sensitive, simple, quick, economical method to screen gene mutation in hereditary multiple exostosis. Show less
Wei Li, Zheng-Mao Hu, Zhi-Guo Xie+4 more · 2007 · Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences · added 2026-04-24
To explore the disease associated gene mutation of multiple exostoses by family analysis. Polymerase chain reaction and DNA sequencing were used to detect the mutation hot spot regions of EXT1 and EXT Show more
To explore the disease associated gene mutation of multiple exostoses by family analysis. Polymerase chain reaction and DNA sequencing were used to detect the mutation hot spot regions of EXT1 and EXT2 gene, while restriction fragment length polymorphism was performed to screen the mutation. We found a novel heterozygous mutation c.811T ->C in EXT1 gene of patients, which resulted in the substitution of histidine for tyrosine at codon 271 in this hereditary multiple exostoses family. The mutation was not found in the unaffected family members, nor in the 100 unrelated normal individual, which was unreported before. The novel mutation Y271H is the disease-causing mutation in the hereditary multiple exostoses family. Show less
The basic/helix-loop-helix (bHLH) proteins are important components of the transcriptional regulatory network, controlling a variety of biological processes, especially the development of the central Show more
The basic/helix-loop-helix (bHLH) proteins are important components of the transcriptional regulatory network, controlling a variety of biological processes, especially the development of the central nervous system. Until now, reports describing the regulatory network of the bHLH transcription factor (TF) family have been scarce. In order to understand the regulatory mechanisms of bHLH TFs in mouse brain, we inferred their regulatory network from genome-wide gene expression profiles with the module networks method. A regulatory network comprising 15 important bHLH TFs and 153 target genes was constructed. The network was divided into 28 modules based on expression profiles. A regulatory-motif search shows the complexity and diversity of the network. In addition, 26 cooperative bHLH TF pairs were also detected in the network. This cooperation suggests possible physical interactions or genetic regulation between TFs. Interestingly, some TFs in the network regulate more than one module. A novel cross-repression between Neurod6 and Hey2 was identified, which may control various functions in different brain regions. The presence of TF binding sites (TFBSs) in the promoter regions of their target genes validates more than 70% of TF-target gene pairs of the network. Literature mining provides additional support for five modules. More importantly, the regulatory relationships among selected key components are all validated in mutant mice. Our network is reliable and very informative for understanding the role of bHLH TFs in mouse brain development and function. It provides a framework for future experimental analyses. Show less
APPL1 is an effector of the small GTPase Rab5. Together, they mediate a signal transduction pathway initiated by ligand binding to cell surface receptors. Interaction with Rab5 is confined to the amin Show more
APPL1 is an effector of the small GTPase Rab5. Together, they mediate a signal transduction pathway initiated by ligand binding to cell surface receptors. Interaction with Rab5 is confined to the amino (N)-terminal region of APPL1. We report the crystal structures of human APPL1 N-terminal BAR-PH domain motif. The BAR and PH domains, together with a novel linker helix, form an integrated, crescent-shaped, symmetrical dimer. This BAR-PH interaction is likely conserved in the class of BAR-PH containing proteins. Biochemical analyses indicate two independent Rab-binding sites located at the opposite ends of the dimer, where the PH domain directly interacts with Rab5 and Rab21. Besides structurally supporting the PH domain, the BAR domain also contributes to Rab binding through a small surface region in the vicinity of the PH domain. In stark contrast to the helix-dominated, Rab-binding domains previously reported, APPL1 PH domain employs beta-strands to interact with Rab5. On the Rab5 side, both switch regions are involved in the interaction. Thus we identified a new binding mode between PH domains and small GTPases. 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