Ethanol Withdwawal QTL and Candidate Genes

乙醇戒断QTL和候选基因

• 批准号: 6928367
• 负责人: KARI J BUCK
• 金额: $ 7.62万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6928367
• 关键词: Ethanol; Withdwawal; QTL; Candidate; Genes

DESCRIPTION (provided by applicant): Quantitative trait loci (QTLs) are chromosomal regions containing genes that influence a complex trait such as alcohol (ethanol) withdrawal severity. We have mapped several QTLs that jointly have a major influence on the severity of alcohol withdrawal in populations derived from the C57BL/6Jo(B6) and DBA/2J (D2) inbred mouse strains. The three largest QTLs (all LOD > 5, p < 2x10 -6) are on distal chromosome 1, mid chromosome 4, and proximal chromosome 11. Based on mouse-human homology, the human counterparts of the three mouse QTLs map to human chromosomes lq22-32, 9p24-23, and 5q31-35, respectively. During the current period of AAl1114, we have identified Kcnj9, Mpdz, and Gabrg2 as promising candidate genes for the mouse chromosome 1, 4 and 11 QTLs, respectively. These promising candidate genes map within the QTL interval and show genotype-dependent differences in gene expression and/or coding sequence (structural differences) that may underlie the QTL. Kcnj9 encodes GIRK3, a member of the G-protein-activated inwardly rectifying potassium channel family. Mpdz encodes a multiple PDZ domain protein. Gabrg2 encodes the GABAA receptor gamma 2 subunit. For the gene(s) underlying a QTL, genotype-dependent (allelic) differences in gene expression and/or coding sequence must be functionally relevant at the protein level, e.g., affect protein expression and/or functional activity. The proposed work will use innovative genetic animal models to test the hypothesis that genotype-dependent differences in these promising candidate genes are functionally relevant at the protein level and influence alcohol withdrawal severity. Using congenic strains to isolate each of the three QTLs against a uniform (inbred) genetic background, and transgenic animal models, we propose to continue toward identification and eventual proof of the genes that underlie each QTL. To accomplish this, we propose the following. (1) Promising candidate genes will be tested for differences between the congenic strain and background strain in their protein product expression using Western blot analysis. (2) Promising candidate genes will be tested for differences between the congenic strain and background strain in the functional activity of their protein products. (3) Kcnj9 (GIRK3) knockout and their wild-type littermates will be behaviorally tested for alcohol withdrawal severity. (4) Conventional and conditional Gabrg2 knockdown mice (i.e., heterozygotes derived from gamma 2 subunit knockout mice) and their wild-type littermates will be behaviorally tested for alcohol withdrawal severity

描述（由申请人提供）：定量性状基因座（QTL）是染色体区域，其中包含影响复杂性状的基因，例如酒精（乙醇）戒断严重程度。我们已经绘制了几个QTL，这些QTL对源自C57BL/6JO（B6）和DBA/2J（D2）近交小鼠菌株的种群中酒精的严重程度产生了重大影响。三个最大的QTL（所有LOD> 5，p <2x10 -6）在远端染色体上，中部染色体4和近端染色体11。基于小鼠 - 人类同源性，三种小鼠QTLS的人类QTLS映射到人类QTLS映射到人类染色体染色体LQ22-22-32，9p22-9p24-23，9p24-23，and 5q31-1-31-1-31-1-31-1-31-1-31-31-31-35 q.31--x.35 q.31--xy。在当前AAL1114期间，我们分别将KCNJ9，MPDZ和GABRG2确定为小鼠1、4和11 QTL的有前途的候选基因。这些有前途的候选基因在QTL间隔内映射，并显示基因表达和/或编码序列（结构差异）的基因型依赖性差异，这些序列可能是QTL的基础。 KCNJ9编码GIRK3，这是G蛋白激活的内部整流钾通道家族的成员。 MPDZ编码多个PDZ域蛋白。 GABRG2编码GABAA受体伽马2亚基。对于基因QTL的基因，基因型依赖性（等位基因）在基因表达和/或编码序列上的差异必须在蛋白质水平上具有功能相关，例如影响蛋白质表达和/或功能活性。拟议的工作将使用创新的遗传动物模型来检验以下假设：这些有前途的候选基因中基因型依赖性差异在蛋白质水平上具有功能相关并影响酒精戒断的严重程度。使用先天性菌株将三个QTL中的每个QTL隔离到均匀（近交）遗传背景和转基因动物模型中，我们建议继续朝着鉴定和最终证明每个QTL的基因的证明。为此，我们提出以下内容。 （1）使用Western印迹分析，将测试有前途的候选基因在其蛋白产物表达中的先天性应变与背景菌株之间的差异。 （2）将测试有希望的候选基因在其蛋白质产物功能活性中的先天性菌株和背景菌株之间的差异。 （3）KCNJ9（GIRK3）敲除及其野生型同窝工人将在行为上测试戒酒严重程度。 （4）常规和有条件的GABRG2敲低小鼠（即，源自伽玛2亚基敲除小鼠的杂合子）及其野生型同窝仔，以行为测试酒精戒断严重程度