沉默MARCH2通过ATF4-CHOP-TRIB3-AKT-MTOR轴调控结肠癌细胞自噬

目的探讨结肠癌细胞中MARCH2调控自噬的机制。方法采用RNA干扰技术和Western blot法检测沉默MARCH2的结肠癌细胞中内质网应激相关蛋白水平、TRIB3蛋白水平、AKT-MTOR信号通路及自噬水平的相关性。结果沉默MARCH2的结肠癌HCT116细胞中AKT-MTOR信号减弱,TRIB3、CHOP和ATG12-ATG5结合物蛋白水平升高。沉默CHOP会引起TRIB3的蛋白水平降低;敲减TRIB3引起AKT-MTOR信号有所回升;敲减ATF4导致CHOP和TRIB3蛋白水平降低,AKT-MTOR信号回升,ATG12-ATG5结合物水平降低。结论沉默MARCH2可能通过上调CHOP,从而升高TRIB3,导致AKT-MTOR抑制,最终促进自噬发生。ATF4-CHOP-TRIB3-AKT-MTOR轴在沉默MARCH2诱导自噬发生过程中起非常重要的作用。     

TRIB3参与血管动脉粥样硬化机制的探讨

正常内皮细胞功能的障碍首先表现为细胞信号蛋白表达的改变或缺陷,引起相应细胞的生物学功能降低,从而加速相关疾病的发生与进展.TRIB3是肥胖、糖尿病和动脉粥样硬化等代谢性疾病的关键枢纽蛋白,通过胰岛素抵抗、内质网应激、脂质代谢等一系列途径,加速血管动脉粥样硬化的形成与进展.因此,本文旨在探讨TRIB3如何调控机体中血脂水平、血糖代谢、血管活性,加速血管动脉粥样硬化形成的机制所在.     

怀牛膝对2型糖尿病大鼠肝脏IDE基因mRNA表达的影响

目的研究怀牛膝（Achyranthes bidentata Blume,BL）水煎剂对2型糖尿病大鼠肝脏胰岛素酶（insulin-degrading enzyme,IDE）基因mRNA表达的影响.方法随机选取以不同剂量怀牛膝水煎剂灌胃的2型糖尿病大鼠每组10只,以生理盐水灌胃的2型糖尿病大鼠及正常对照组大鼠各10只,用RT-PCR法测定大鼠肝脏胰岛素酶基因mRNA的表达.结果2型糖尿病大鼠模型组IDE基因mRNA的表达高于正常组（P＜0.05）.怀牛膝治疗组各组IDE基因mRNA的表达均低于2型糖尿病大鼠模型组（P＜0.05）,并且与正常对照组相比无显著性差异（P＞0.05）.结论怀牛膝水煎剂通过抑制肝胰岛素酶基因mRNA的表达.     

MTNR1B基因多态性与2型糖尿病

2型糖尿病是一种与多基因、多因素相关联的具有明显遗传异质性的疾病.全基因组关联分析显示MTNR1B基因变异与胰岛素分泌、葡萄糖水平以及2型糖尿病发病有显著相关性.MTNR1B基因是2型糖尿病重要的易感基因之一,其变异可能通过减少β细胞胰岛素分泌,从而增加2型糖尿病的易感性.     

MTNR1B基因多态性与2型糖尿病

2型糖尿病是一种与多基因、多因素相关联的具有明显遗传异质性的疾病.全基因组关联分析显示MTNR1B基因变异与胰岛素分泌、葡萄糖水平以及2型糖尿病发病有显著相关性.MTNR1B基因是2型糖尿病重要的易感基因之一,其变异可能通过减少β细胞胰岛素分泌,从而增加2型糖尿病的易感性.     

2型糖尿病、肥胖、骨质疏松相关基因被发现

1 2型糖尿病基因位点再被证实:2 0 0 1年中国医科院方福德教授首次定位中国人2型糖尿病遗传易感基因UrotensinⅡ基因与2型糖尿病相关。同年北大人民医院研究人员证实UrotensinⅡ(尾加压素)基因中一个单核苷酸多态性位点(SNP)rs2 2 86 4 8(代码)与2型糖尿病有关。(健康报,2 0 0 2 - 7- 9)2 人类肥胖新基因被发现:英国科学家最近发现,在人体第10号染色体上的GAD2 基因与食欲食量过剩肥胖有关,并在儿童遗传因素分析中得到预测。(健康报,2 0 0 3- 11- 3)3 骨质疏松症基因发现:冰岛科学家最近报道,在2 0号染色体一个区域上一个BMP2的相关基…     

神经源分化因子基因多态性与2型糖尿病的关联性研究

目的　探讨神经源分化因子 (neurogenic differentiation factor 1,Neuro D)基因多态性与 2型糖尿病发生的关联性。方法　运用错配聚合酶链反应 -限制性片段长度多态性方法检测了中国湖北地区汉族 32 4例 2型糖尿病 (其中以发病年龄 40岁为界 ,分为早发及晚发两组 )及 12 4名正常对照者 ,Neuro D基因第 45位密码子碱基变异 (GCC→ ACC)。结果　 Neuro D基因在所测人群中未发现有纯合变异者。在早发 2型糖尿病组 ,其 AT基因型频率为 2 6 .8% ,与正常对照组 (10 .5 % )及晚发 2型糖尿病组 (11.6 % )比较 ,差异有显著性 (分别为χ2 =7.85 ,P=0 .0 0 5 ;χ2 =8.81,P=0 .0 0 3) ;Thr45等位基因频率在早发 2型糖尿病组及正常对照组、晚发 2型糖尿病组分别为 13.4%、5 .2 %和 5 .8% ,差异亦有显著性 (χ2 =7.15 ,P=0 .0 0 8;χ2 =8.13,P=0 .0 0 4) ;晚发 2型糖尿病组与正常对照组比较 ,Ala45 Thr基因型频率 (11.6 % vs10 .5 % ,P>0 .0 5 )及等位基因频率 (5 .8% vs 5 .2 % ,P>0 .0 5 )差异不明显 ,Thr45等位基因与早发 2型糖尿病发生相关 (OR=2 .5 2 ,95 % CI:1.42～ 4.49) ;基因型为 AT型的 2型糖尿病患者其空腹血浆 C肽水平较 AA型患者低 ,差异有显著性 (P<0 .0 5 )。结论　 Neuro D基因多态性与早发 2型糖尿     

TRIB1与癌症相关性的研究进展

TRIB1是果蝇Tribbles蛋白的一个同源蛋白.在人体内,TRIB1缺乏催化结构域,因此无激酶活性,但可作为支架蛋白,参与蛋白与蛋白之间的相互作用.TRIB1已被证实在多种癌症中发挥作用,包括急性髓细胞白血病、前列腺癌、卵巢癌、结直肠癌等.此文就TRIB1的功能与特点以及在癌症方面的研究进展加以综述.     

固醇调节元件结合蛋白1c基因多态性rs2297508、rs11868035与甘肃汉族、东乡族人群2型糖尿病的相关性

目的 探讨固醇调节元件结合蛋白1c(sterol regulatory element binding protein-lc,SREBP-lc)基因多态性rs2297508、rs11868035在甘肃汉族、东乡族人群中的分布及其与2型糖尿病(type 2diabetes mellitus,T2DM)的相关性.方法 选择汉族2型糖尿病患者342例以及正常对照343人,东乡族2型糖尿病患者218例以及正常对照238人,采用聚合酶链反应-变性高效液相色谱法检测SREBP-1c基因型,采用氧化酶法或放免法测定血糖、胰岛素及血脂水平.采用卡方检验进行统计学分析.结果 SREBP-lc基因多态位点rs2297508、rs11868035在汉族和东乡族正常对照者中的基因型和等位基因频率分布差异无统计学意义(P＞0.05).上述位点在汉族、东乡族人群2型糖尿病患者C等位基因和CC基因型频率均明显高于对照组,差异均有统计学意义(P＜0.01).在汉族对照组中,rs2297508的C等位基因携带者的低密度脂蛋白胆固醇水平明显高于GG者,其差异有统计学意义(P＜o.05).在东乡族对照组中,CC基因型的低密度脂蛋白胆固醇水平明显高于GG者,其差异有统计学意义(P＜0.05).结论 SREBP-lc基因多态性rs2297508、rs11868035在甘肃汉族和东乡族人群中均与2型糖尿病发病存在关联.C等位基因可能是罹患2型糖尿病的危险因素之一.上述多态性在汉族和东乡族人群中的分布并无差异.SREBP-le基因多态性rs2297508可能与低密度脂蛋白胆固醇升高有关.     

2型糖尿病的易感基因研究进展

2型糖尿病是一种多基因遗传的复杂疾病,基因型一表型之间关系错综复杂,迄今仍然未能确定2型糖尿病的致病基因.本文主要阐述近年来2型糖尿病易感基因主要研究成果.     

Heterozygosity for MICA5.0/MICA5.1 and HLA-DR3-DQ2/DR4-DQ8 are independent genetic risk factors for latent autoimmune diabetes in adults

Major histocompatibility complex class I chain-related gene A (MICA) encodes polymorphic, stress-inducible antigens recognized by gammadelta T cells within the intestinal epithelium. MICA microsatellite polymorphism has been implicated to be related to different autoimmune diseases. Ninety-eight patients with type 1 diabetes (median age, 35 years; range, 9-89 years and 51 patients with latent autoimmune diabetes (LADA; median age, 48 years; range, 19-79 years) were compared with 113 healthy control patients (median age, 35 years; range, 19-65 years) to study the importance of MICA-microsatellite polymorphism and HLA-DR-DQ as genetic risk factors for diabetes. The different factors were compared univariately and by logistic regression analysis. In the logistic regression model, heterozygosity for MICA5.0/5.1 was a significant risk factor for LADA (odds ratio [OR] = 12; 95% confidence interval [95%CI], 2.5-59) as well as heterozygosity for HLA-DR3-DQ2/DR4-DQ8 (OR = 15; 95%CI, 2.7-84). None of the MICA polymorphisms were related to type 1 diabetes. Heterozygosity for HLA-DR3-DQ2/DR4-DQ8 was a risk factor for type 1 diabetes (OR = 14; 95%CI, 2.9-66) as well as DR4-DQ8/x (OR = 2.8; 95%CI, 1.4-5.9). HLA-DR15-DQ6 was protective for type 1 diabetes (OR = 0.12; 95%CI, 0.015-0.96). We concluded that both heterozygosity for MICA5.0/5.1 and HLA-DR3-DQ2/DR4-DQ8 are separate risk factors for LADA, but that heterozygosity for HLA-DR3-DQ2/DR4-DQ8 and DR4-DQ8 alone are most important for type 1 diabetes.     

Protection from renal fibrosis,putative role of TRIB3 gene silencing

Background

Renal fibrosis is thought to be the common pathway in most cases of chronic kidney disease. Recently, TRIB3 was found to play an important role in progression of cardiac fibrosis in an insulin-resistant state. We investigated whether TRIB3 might participate in the pathogenesis of renal fibrosis in insulin-resistant rats.

Methods

We randomly separated 40 male Sprague–Dawley into 4 groups for treatment (n = 10 each): control and high-fat diet (HFD) with TRIB3 siRNA adenovirus transfection, vehicle transfection or HFD alone. Insulin resistance markers were measured. Renal tissues were stained with hematoxylin and eosin, Masson's trichrome and periodic acid-Schiff.

Results

Rats with HFD showed insulin resistance and TRIB3 overexpression. Upregulated TRIB3 expression could induce renal fibrosis accompanied by increased phosphorylation of extracellular signal-regulated kinase (ERK). Also, TRIB3 siRNA knockdown could ameliorate renal fibrosis, which was accompanied by decreased phosphorylation of ERK.

Conclusions

TRIB3 gene silencing can attenuate renal fibrosis for beneficial effect on the development of renal fibrosis in chronic kidney disease in rat.     

Analysis of IL4R haplotypes in predisposition to multiple sclerosis

We have investigated the association of multiple sclerosis (MS) with polymorphisms in the IL4R gene in 332 single-case MS families. IL4R encodes a subunit of the interleukin-4 receptor, a molecule important for T-cell development and differentiation, and is a gene shown to be associated with immune-related diseases such as asthma and type I diabetes. By genotyping two promoter and eight coding IL4R SNPs and identifying haplotypes (complex alleles) in the MS families, stratified for HLA genotype, we have observed evidence of the association of the IL4R gene to MS. In particular, we have identified a specific susceptibility haplotype, and observe that the risk is conferred primarily to individuals not carrying the high MS-risk HLA DR2 (DRB1(*)1501-DQB1(*)0602) haplotype (nominal P=0.009). These findings suggest a potentially important role for the IL4R gene in predisposition to MS, and provide further evidence of its relevance as a candidate gene for immune-related diseases.     

TRB3 Q84R基因多态性与不同表型多囊卵巢综合征的相关性

目的探讨TRB3 Q84R基因多态性与不同表型多囊卵巢综合征（Ⅰ型：O＋H＋P;Ⅱ型：O＋H;Ⅲ型：H＋P;Ⅳ型：O＋P）的相关性。方法采用聚合酶链反应-限制性片段长度多态性（polymerase chain reaction-restriction frag-ment length polymorphism,PCR-RFLP）方法检测TRB3 Q84R的基因多态性。结果 TRB3 Q84R基因型频率分布在Ⅰ型P-COS组（O＋H＋P）与对照组之间有显著性差异（P〈0.05）;其余PCOS表型与对照组之间基因型频率分布无显著性差异（P〉0.05）。结论 TRB3 Q84R基因多态性与Ⅰ型PCOS相关。     

Mutation spectrum of phenylketonuria in Iranian population

Identification of molecular basis of phenylketonuria (PKU) in Iran has been accomplished through the analysis of 248 unrelated chromosomes from 124 Iranian classic PKU subjects. Phenylalanine hydroxylase (PAH) gene mutations were analyzed through a combined approach in which p.S67P, p.R252W, p.R261Q, p.R261X, p.L333F, IVS10-11G>A, IVS11+1G>C, p.L364del, p.R408Q and p.R408W mutations were first screened by PCR of PAH gene exons 3, 7, 10, 11 and 12, followed by digestion with the appropriate digestion enzymes. Subsequently SSCP analysis for exons 2, 6, 7 and 11 of the PAH gene and finally, sequencing of 13 PAH gene exons have been used to study uncharacterized PKU chromosomes. 26 different mutations were found. The predominant mutation in this population sample was IVS10-11G>A, with a frequency of 24.6%. Nine mutations (IVS10-11G>A, p.R261Q, p.P281L, IVS11+1G>C, p.K363>NFS, p.R243X, IVS2+5G>C, p.R261X and p.R252W) represent almost 84% of all PKU chromosomes studied. IVS10-11G>A mutation is the major PKU-causing mutation throughout the Mediterranean region. The finding of the high prevalence of this mutation in Iranian population is consistent with the historical and geographical links between Iranian and Mediterranean populations.     

Molecular scanning of the human sorbin and SH3-domain-containing-1 (SORBS1) gene: positive association of the T228A polymorphism with obesity and type 2 diabetes

In the mouse, the SH3P12 or the c-Cbl-associated protein (CAP) has been shown as an important signaling molecule in insulin-stimulated glucose uptake. The human homolog for the sorbin and SH3-domain-containing-1 gene, termed SORBS1, might play a role in human disorders with insulin resistance. To explore the genetic role of SORBS1 in human obesity and type 2 diabetes, we investigated the nucleotide polymorphisms in the SORBS1 gene with molecular scanning. After scanning for a total of 13,136 bp in each of 40 chromosomes, we have identified 14 single nucleotide polymorphisms (SNPs) in the human SORBS1 gene. Among them, two SNPs affected amino acid coding (R74W and T228A), four occurred within exons but did not affect amino acid coding, and the remaining eight occurred within introns, which were located outside of the consensus region of the splicing mechanism. Further studies in 202 non-obese, 113 obese and 455 subjects with type 2 diabetes revealed that the A-allele of the T228A polymorphism in exon 7 exerted a protective role for both obesity [relative risk 0.466; 95% confidence interval (95% CI) 0.265-0.821] and diabetes (relative risk 0.668; 95% CI 0.472-0.945). Neither allele of the R74W polymorphism was associated with either obesity or diabetes. In conclusion, our results suggest that the A228 allele of the T228A polymorphism of the SORBS1 gene is a protective factor for both obesity and diabetes, and also imply that the SORBS1 gene plays an important role in the pathogenesis of human disorders with insulin resistance.     

A type 2 diabetes-associated polymorphic ARE motif affecting expression of PPP1R3 is involved in RNA-protein interactions.

We have previously described a polymorphism in the 3' untranslated region (UTR) of the PPP1R3 gene that encodes the muscle-specific glycogen-targeting regulatory PP1 subunit. This polymorphism alters the distance between two putative mRNA-destabilizing ATTTA (AUUUA) motifs and is distinguished by a 10-nucleotide (allele ARE1) vs a 2-nucleotide interval (allele ARE2). ARE2 is associated with insulin resistance as well as increased prevalence of type 2 diabetes in the Pima Indians, and correlates with reduced expression of this subunit in vivo, causing a 10-fold half-life reduction of reporter mRNA in NIH3T3 cells. Gel shift assays, Northwestern blotting, and RNA-protein UV crosslinking revealed three proteins (43, 80, and 139 kDa) binding to the polymorphic ARE region in these cells. The interactions are sequence specific, and can be suppressed by an unlabeled competitor in a dose-dependent manner. The less stable ARE2 allele shows at least 2-fold higher relative protein binding, indicating that the polymorphic ARE region has a mRNA-destabilizing role. We suggest that the increased protein binding to ARE2 contributes to a faster degradation of PPP1R3 mRNA carrying this allele, and the resulting lower concentration of the protein contributes to insulin resistance, thus increasing the risk for development of type 2 diabetes.     

神经元钙传感蛋白R102Q突变体的动力学构象特征

背景：神经元钙传感蛋白参与多种生理功能,在大脑皮质不同脑区都有很高的分布。在自闭症患者基因测序中识别出神经元钙传感蛋白第102个氨基酸精氨酸ARG102突变成谷氨酰胺Glu102(R102Q)。实验研究显示,R102Q突变对神经元钙传感蛋白局部区域影响很大,发生本质性的构象改变。 目的：确定神经元钙传感蛋白单一氨基酸R102Q突变引起结构构象动力学变化的具体原因。 方法：采用计算机分子动力学模拟的方法,进行6个独立的、模拟时间是450 ns的全原子动力学模拟。 结果与结论：①神经元钙传感蛋白R102Q突变对蛋白整体结构影响不大,在整个模拟过程中都没有进行大的构象重组,但导致螺旋改变,结构更加稳定。②R102Q突变导致盐桥网络发生改变,一方面降低了L2的柔性,使其更加稳定;另一方面改变L3在疏水口袋中的位置,使其在疏水口袋中更加舒展。结果表明,螺旋在蛋白结构稳定中起到一定的作用,盐桥改变也是蛋白动力学变化的重要原因。这项研究可能从分子的层面和结构的视角,为与R102Q突变有关的蛋白质功能缺失提供理论参考。  中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

CACNA1A R1347Q: a frequent recurrent mutation in hemiplegic migraine

Of the 18 missense mutations in the CACNA1A gene, which are associated with familial hemiplegic migraine type 1 (FHM1), only mutations S218L, R583Q and T666M were identified in more than two independent families. Including the four novel families presented here, of which two represent de novo cases, the R1347Q mutation has now been identified in six families. A genotype-phenotype comparison of R1347Q mutation carriers revealed a wide clinical spectrum ranging from (trauma triggered) hemiplegic migraine with and without ataxia, loss of consciousness and epilepsy. R1347Q is the third most frequent mutation in hemiplegic migraine patients and should therefore be screened with priority for confirmation of clinical diagnosis. This study clearly demonstrates that the availability of multiple families better reflects the full clinical spectrum associated with FHM1 mutations.