A GENETIC ANALYSIS OF MINIBRAIN KINASE IN C. ELEGANS

线虫小脑激酶的遗传分析

• 批准号: 6209924
• 负责人: WILLIAM B RAICH
• 金额: $ 3.24万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6209924
• 关键词: Caenorhabditis elegans; Downs syndrome; gene targeting; isozymes; neurogenetics; phenotype; protein kinase

The goal of this research proposal is to identify molecular pathways involving minibrain kinase (mnbK), both in normal neuronal function and in the cognitive defects of Down syndrome. Studies of partial trisomy of chromosome 21 suggest that a considerable portion of the Down syndrome phenotype result from a 2-Mb region at the 21g22.2 region; mnbK localizes to this genomic region. Overexpression of mnbK in mice causes severe defects in learning and memory, strongly implicating mnbK in the cognitive defects of Down syndrome. Currently, the substrates and regulators of mnbK are unknown. To elucidate this pathway, the Caenorhabditis elegans mnbK homologues mbk-1 and mbk-2, will be investigated. I propose to characterize the expression and subcellular localization of the mbk gene products, generate null alleles via chemical mutagenesis coupled with population PCR, and simulate the Down condition by overexpressing the wildtype and activated gene products. As a tool for determing the focus of MBK activity, the tetracycline-dependent transactivator system will be adapted to C. elegans, a system that permits temporally and spatially regulated gene expression. Candidate genes will be tested to determine if they belong to a mbk pathway, and pilot suppressor and/or enhancer screens will be performed to identify upstream and downstream components in an unbiased manner.

这项研究的目的是确定涉及minibrain激酶（mnbK）的分子通路，无论是在正常的神经元功能和唐氏综合征的认知缺陷。对21号染色体部分三体的研究表明，相当一部分唐氏综合征表型是由21g22.2区域的2-Mb区域引起的; mnbK定位于该基因组区域。mnbK在小鼠中的过度表达导致学习和记忆的严重缺陷，强烈暗示mnbK在唐氏综合征的认知缺陷中。目前，mnbK的底物和调节剂是未知的。为了阐明这一途径，将研究秀丽隐杆线虫mnbK同系物mbk-1和mbk-2。 我建议的MBK基因产物的表达和亚细胞定位的特点，通过化学诱变加上人口PCR产生无效等位基因，并通过过表达的野生型和激活的基因产物模拟下的条件。四环素依赖的反式激活因子系统作为确定MBK活性中心的工具，将适用于C. elegans，一个允许时间和空间调控基因表达的系统。将测试候选基因以确定它们是否属于mbk途径，并且将进行先导抑制子和/或增强子筛选以无偏的方式鉴定上游和下游组分。