RAPID ISOLATION OF DIET-RESPONSIVE OBESITY GENES

每个人的体重是由复杂的混合 环境和遗传的影响。人口平均水平可以证明 统计遗传学证明生物学时的环境影响 对肥胖的影响。然而，这些方法不能解释个体 体重的差异，也就是为什么有些人肥胖，有些人不肥胖。 肥胖的个体原因可以通过寻找特定的基因来确定。 具有自然变异(等位基因)，其功能因人而异。许多 肥胖基因已经被发现，但其他基因仍未被发现。这个 首席研究员(PI)的目标是识别体内的肥胖基因，以 了解它们是如何影响体内脂肪积累的，并继续其 体外研究解偶联蛋白(UCPs)的结构和功能 是候选的肥胖基因。为了研究体重调节的基础， Pi将：1)确定导致同源基因小鼠肥胖的基因(S) 模型，2)研究解偶联蛋白的作用机制，3)寻找 同源基因小鼠品系中受饮食调控的新基因。私家侦探和他的 合作者最近证明了C7.H1同源毒株，它 比它的背景株瘦得多，有两条相连的染色体 肥胖基因，尽管与背景基因有99%的相同之处。 他们现在提议生产五个亚基因菌株(供体较小 区域)，以确定每个基因座背后的基因。UCP2和3和TUBBY 是远端轨迹的位置候选者。PI将通过以下方式测试他们的角色 从同源和背景菌株中确定序列并通过 检测信使核糖核酸和蛋白质水平。他们还将使用mRNAs表达 从C7.H1同源和亚同源菌株中鉴定新基因 肥胖候选基因。PI将把他对UCP2-3的研究扩展为 C7.H1同源基因模型候选基因的应用 UCPs的结构/功能研究。解偶联蛋白可能影响机体 通过降低线粒体的效率来增加体重和代谢率 将卡路里转化为三磷酸腺苷。已发布数据，以及本报告中的初步数据 提案表明，UCP受几种配体的调节，例如 维甲酸、核苷酸和脂肪酸。PI将测试质子传输 已建立的和新的候选UCPs在脂质体中的活性并将进行研究 用位置定向自旋标记(SDSL)电子顺磁研究UCP结构 共振(EPR)。这些研究将与现场指导协调 突变来检验关于质子运输机制的假说。

Individual body weights are determined by a complex blending of environmental and genetic influences. Population averages can demonstrate environmental influences while statistical genetics demonstrates biological influences on obesity. However, these methods cannot explain individual differences in body weight, i.e., why some people are obese and some are not. The individual causes for obesity may be determined by finding specific genes with natural variants (alleles) whose function varies among people. Many obesity genes have been identified, but others remain undiscovered. The principal investigator's (PI) goals are to identify obesity genes in vivo, to understand how they influence body fat accumulation, and to continue their in vitro work on the structure and function of uncoupling proteins (UCPs), which are candidate obesity genes. To study the basis for body weight regulation, the PI will: 1) determine the gene(s) that underlies obesity in a congenic mouse model, 2) study the mechanisms for uncoupling protein action, and 3) search for novel genes regulated by diet in congenic mouse strains. The PI and his collaborators have recently demonstrated that the C7.H1 congenic strain, which is significantly leaner than its background strain, has two linked chromosomal obesity loci, despite being 99 percent genetically identical to the background. They now propose to produce five subcongenic strains (with smaller donor regions) to identify the gene that underlies each locus. UCP2 and 3 and tubby are positional candidates for the distal locus. The PI will test their role by determining sequence from the congenic and background strains and by measurement of mRNA and protein levels. They will also use mRNA expression profiles from the C7.H1 congenic and subcongenic strains to identify novel obesity candidate genes. The PI will extend his studies of UCP2-3 as positional candidate genes for the C7.H1 congenic model by the application of structure/function studies of UCPs. Uncoupling proteins may influence body weight and metabolic rate by decreasing the efficacy with which mitochondria convert calories into ATP. Published data, and preliminary data in this proposal, demonstrate that UCPs are regulated by several ligands, such as retinoids, nucleotides, and fatty acids. The PI will test proton transport activity of established and novel candidate UCPs in liposomes and will study UCP structure by Site-Directed Spin Labeling (SDSL) Electron Paramagnetic Resonance (EPR). These studies will be coordinated with site-directed mutagenesis to test the hypotheses about mechanisms for proton transport.