Positional cloning of obesity genes from congenic mice

位置克隆-通过定位肥胖性状和基因共同出现来识别肥胖基因 一个特定的染色体区域，为发现新的肥胖基因和制造 对导致肥胖的机制的新见解。老鼠已经被用来首次鉴定更多的 人类的肥胖基因比任何其他模型都要多。这项提议的目标是使用位置克隆方法来 鉴定小鼠同源品系中的肥胖基因。同基因的小鼠品系与背景相同 除供体菌株的染色体区域外的菌株。同源基因和同源基因的表型差异 背景是由于供体菌株的等位基因具有与背景菌株不同的功能效应。 为这一提议做出贡献的两个实验室已经鉴定出几个小鼠同源品系 小鼠2号染色体上与人类同源区域的肥胖表型的统计学意义 在20号染色体上，已经定位了几个肥胖数量性状基因座。我们的一般假设是 同源基因供体区域中的一个或多个基因或转录本影响肥胖。我们的具体工作 假设肥胖背后的基因/转录本可以在大多数先天基因中识别出来。我们建议 七个具体目标。我们将：确定饮食、性别和年龄对肥胖的影响 1)，通过培育更小的同源基因来识别包含肥胖基因的最小染色体基因座 保留肥胖表型的供体区域(目标2)，寻找差异表达的供体区域基因 使用八种肥胖组织RNA的全基因组微阵列(目标3)，对选定的供体区域进行序列测定 基因(目标4)，确定差异表达基因的mRNA水平的顺式或反式控制(目标5)， 根据Aims3-5的结果(目标6)，生产过表达10个候选基因的转基因小鼠 并确定可能影响肥胖的microRNAs或其他转录的非编码基因(目标7)。《长河》 学期的结果是，我们将至少识别出一个新的、强大的和看似合理的肥胖基因。

Positional cloning - the identification of obesity genes by co-incidence of mapped obesity traits andgenes to a specific chromosomal region, provides a powerful method to discover novel obesity genes and to make novel insights into the mechanisms causing obesity. Mice have been used for the first identification of more human obesity genes than any other model. The goal of this proposal is to use positional cloning methods to identify obesity genes in mouse congenic strains. Congenic mouse strains are identical to a background strain except for a chromosomal region from a donor strain. Phenotype differences between congenic and background are due to alleles of the donor strain with functional effects different from the background strain. The two laboratories contributing to this proposal have identified several mouse congenic strains with statistically significant phenotypes for obesity on mouse chromosome 2 in a region homologous to human chromosome 20, where several obesity quantitative trait loci have been mapped. Our general hypothesis is that one or more genes or transcripts in the congenic donor regions influences obesity. Our specific working hypothesis is that genes/transcripts underlying obesity can be identified for most congenics. We propose seven Specific Aims. We will: determine diet, sex and age effects on obesity in the founding congenics (Aim 1), identify minimal chromosomal loci containing obesity genes by breeding congenics with ever smaller donor regions that retain obesity phenotypes (Aim 2), find differentially expressed donor region genes with whole genome microarrays using RNAfrom eight obesity tissues (Aim 3), sequence selected donor region genes (Aim 4), determine cis or trans control of mRNA levels for differentially expressed genes (Aim 5), produce transgenic mice overexpressing ten candidate genes prioritized by the results of Aims3-5 (Aim 6) and identify microRNAs or other transcribed non-coding genes that may influence obesity (Aim 7). The long term outcome is that we will identify at least one novel and strong and plausible obesity gene.