Study of Resistin gene expression in peripheral blood mononuclear cell and its gene polymorphism in a small range population

INTRODUCTION Recently discovered as an endocrine organ, adi-pose tissue can secrete many cytokines such as Re-sistin, adiponectin and free fatty acids, and receives much attention in the study of insulin resistance and type 2 diabetes mellitus (T2DM). As a peptide hor-mone secreted by adipocyte, Resistin is considered to be the linkage between obesity and insulin resistance (Steppan et al., 2001). Most studies on Resistin in-vestigate adipose tissue. In this experiment we de-tected t…     

运动、氧化应激与DNA损伤和修复

在分子和基因水平上对运动时氧化应激损伤、氧化应激与DNA损伤以及DNA损伤和修复等几方面关系进行探讨,旨在探讨运动疲劳和损伤发生的分子生物学基础,并对未来运动医学研究的发展趋势进行展望。     

miRNA:一种新的基因调控元件

miRNA(microRNA)是一类长约22个核苷酸的小分子非编码RNA。近年来,科学家发现miRNA与基因表达调控密切相关,miRNA可通过与靶mRNA特异性的碱基配对,引起靶mRNA的降解,抑制其翻译,或以其它形式的调节机制抑制靶基因的表达。本文概述了miRNA特点、生物合成过程、功能以及作用机制。     

低氧和运动经AR- IGF- 1 对骨骼肌蛋白质合成的作用

目的:探讨低氧、运动对骨骼肌蛋白质合成的作用.方法:2月龄雄性SD大鼠40只随机分为对照组、低氧组、运动组、低氧运动组,实验28天后取材测试.结果:(1)运动组AR蛋白表达量、AR活性与骨骼肌总蛋白质含量比对照组显著升高;(2)低氧组骨骼肌睾酮含量、AR蛋白表达量、IGF-1mRNA含量以及肌纤维横截面积较对照组显著降低;AR活性、骨骼肌蛋白质含量较对照组显著升高;(3)低氧运动组AR蛋白表达量、AR活性和骨骼肌总蛋白含量比运动组显著下降.结论:(1)运动后进行低氧暴露比单纯运动更能通过AR含量-AR活性水平抑制蛋白质合成;(2)低氧、运动或低氧运动通过睾酮调节AR数量及活性,最终影响骨骼肌蛋白含量;(3)低氧、运动或低氧运动可通过调节AR转录活性影响IGF-1mRNA表达,最终调节骨骼肌蛋白质合成.     

CD44v6mRNA和HSP70mRNA在胃癌中的表达及研究

目的:检测CD44v6mRNA和HSP70mRNA在胃癌组织中的表达,探讨CD44v6mRNA和HSP70mRNA在胃癌发生发展中的作用.方法:利用核酸原位杂交技术对39例胃癌组织进行检测.结果:CD44v6mRNA和HSP70mRNA在胃癌组织表达的阳性率都为61.54%(24/39),CD44v6mRNA和HSP70mRNA在高分化管状腺癌与低分化管状腺癌中的表达都有显著性差异(P＜0.05),但HSP70mRNA在胃癌组织的表达与性别、年龄、浸润深度及淋巴结有无转移都无关(P＞0.05),而CD44v6mRNA与淋巴结有无转移有关(P＜0.05).结论:CD44v6mRNA和HSP70mRNA在胃癌组织都有较高的表达,两者均可作为评估胃癌预后的指标.     

The polyadenylation code: a unified model for the regulation of mRNA alternative polyadenylation

The majority of eukaryotic genes produce multiple mRNA isoforms with distinct 3′ ends through a process called mRNA alternative polyadenylation (APA). Recent studies have demonstrated that APA is dynamically regulated during development and in response to environmental stimuli. A number of mechanisms have been described for APA regulation. In this review, we attempt to integrate all the known mechanisms into a unified model. This model not only explains most of previous results, but also provides testable predictions that will improve our understanding of the mechanistic details of APA regulation. Finally, we briefly discuss the known and putative functions of APA regulation.     

Sequence- and structure-selective mRNA m5C methylation by NSUN6 in animals

mRNA m⁵C, which has recently been implicated in the regulation of mRNA mobility, metabolism and translation, plays important regulatory roles in various biological events. Two types of m⁵C sites are found in mRNAs. Type I m⁵C sites, which contain a downstream G-rich triplet motif and are computationally predicted to be located at the 5^′ end of putative hairpin structures, are methylated by NSUN2. Type II m⁵C sites contain a downstream UCCA motif and are computationally predicted to be located in the loops of putative hairpin structures. However, their biogenesis remains unknown. Here we identified NSUN6, a methyltransferase that is known to methylate C72 of tRNA^Thr and tRNA^Cys, as an mRNA methyltransferase that targets Type II m⁵C sites. Combining the RNA secondary structure prediction, miCLIP, and results from a high-throughput mutagenesis analysis, we determined the RNA sequence and structural features governing the specificity of NSUN6-mediated mRNA methylation. Integrating these features into an NSUN6-RNA structural model, we identified an NSUN6 variant that largely loses tRNA methylation but retains mRNA methylation ability. Finally, we revealed a weak negative correlation between m⁵C methylation and translation efficiency. Our findings uncover that mRNA m⁵C is tightly controlled by an elaborate two-enzyme system, and the protein-RNA structure analysis strategy established may be applied to other RNA modification writers to distinguish the functions of different RNA substrates of a writer protein.     

"后基因组时代"的营养学研究

飞速发展的基因科技,已将我们带入了"后基因组时代",伴随着基因组学、转录组学的迅猛发展,营养学的研究转向了研究营养与基因的相互作用,即营养基因组学.我们每个人自身的基因不同,某种特定的食物不见得对每个人有相同的"好处"或"坏处".要决定健康,关键要看基因和营养二者的相互作用.通过单核苷酸多态性,以及可以快速检测出mRNA水平的高通量基因表达谱,研究者可以更全面,更深入地了解营养与基因表达的关系,帮助指导人们根据自己的"基因要求",合理的搭配营养,实现营养个体化.     

运动训练对脑缺血再灌注大鼠神经保护作用及PPARγmRNA表达的影响研究

目的:观察运动训练对脑缺血大鼠神经保护作用及对PPARγmRNA表达的影响。方法:SD大鼠40只,随机分为安静对照组10只,模型对照组15只,运动训练组15只。对模型对照组和运动训练组建立脑缺血再灌注模型,后对运动训练组进行跑台训练。3周后,分别对三组大鼠神经功能和PPARγmRNA进行检测。结果:运动训练组大鼠神经功能评分显著高于模型对照组,PPARγmRNA表达显著高于模型对照组。结论:运动训练能对脑组织的保护作用可能与PPARγmRNA的表达升高有关。