Constructing a Conditional Kalirin Null Mouse

构建有条件的 Kalirin 空小鼠

• 批准号: 6954668
• 负责人: RICHARD E MAINS
• 金额: $ 14.5万
• 依托单位: UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-30 至 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6954668
• 关键词: alleles; confocal scanning microscopy; developmental neurobiology; gene targeting; genetically modified animals; guanine nucleotide binding protein; hippocampus; laboratory mouse; mutant; nervous system; neural plasticity; nucleus accumbens; polymerase chain reaction; protein isoforms; protein quantitation /detection; protein structure function

DESCRIPTION (provided by applicant): Kalirin is a large, multidomain Rho GDP/GTP exchange factor (GEF) of the Dbl family found almost exclusively in the nervous system. Based on genetic studies in invertebrates and analysis of genes involved in X-linked mental retardation, Kalirin is expected to play a role in axonal pathfinding and synapse formation. Our studies in rat hippocampal, cortical and sympathetic neurons showed that Kalirin plays a role in axon initiation and outgrowth, dendritic growth, and spine formation and maintenance. Kalirin has two GEF domains with specificity for different Rho family GTPases and a potential kinase domain. In addition to these catalytic domains, it has interactor domains for a variety of proteins. Kalirin expression in the nucleus accumbens and striatum is stimulated by chronic administration of cocaine, with no change in cortical Kalirin levels; Kalirin is also increased following electroconvulsive shock stimulation. The exploratory studies proposed are based on our observations that antisense-mediated elimination of Kalirin expression in organotypic slices and dissociated hippocampal neurons leads first to a reduction in linear spine density followed by simplification of the dendritic tree. Aim 1 is to generate mutant mice that will facilitate studies of neuronal development and plasticity in multiple systems. In order to avoid embryonic or early postnatal lethality, and to allow generation of tissue-specific and developmentally regulated elimination of expression, two mouse lines will be created as floxed alleles. Both will be provided to all qualified investigators without restrictions. One allele will produce the Kalirin-7 null. Kalirin-7 is the most prevalent isoform in the adult brain, with a single Rho GEF domain, terminating with a unique PDZ binding motif. Kalirin-7 appears late in development and is localized to dendritic spines. The second allele will produce the total Kalidn knockout. Both will be bred with available tissue-specific and drug-inducible Cre recombinase mice. Aim 2 will examine the biochemical, histological, and developmental consequences of tissue-specific Kalirin conditional knockouts.

描述（由申请人提供）： Kalirin 是 Dbl 家族的一种大型多域 Rho GDP/GTP 交换因子 (GEF)，几乎只存在于神经系统中。基于无脊椎动物的遗传学研究和 X 连锁智力低下相关基因的分析，Kalirin 有望在轴突寻路和突触形成中发挥作用。我们对大鼠海马、皮质和交感神经元的研究表明，Kalirin 在轴突起始和生长、树突生长以及脊柱形成和维持中发挥作用。 Kalirin 具有两个对不同 Rho 家族 GTPases 具有特异性的 GEF 结构域和一个潜在的激酶结构域。除了这些催化结构域之外，它还具有多种蛋白质的相互作用结构域。长期服用可卡因会刺激伏隔核和纹状体中的 Kalirin 表达，但皮质 Kalirin 水平没有变化；电休克刺激后 Kalirin 也会增加。所提出的探索性研究基于我们的观察，即反义介导的消除器官切片和分离的海马神经元中 Kalirin 表达首先导致线性脊柱密度降低，然后是树突树的简化。目标 1 是培育突变小鼠，以促进多个系统中神经元发育和可塑性的研究。为了避免胚胎或出生后早期致死，并允许产生组织特异性和发育调节的表达消除，将创建两个小鼠品系作为 floxed 等位基因。两者都将不受限制地提供给所有合格的研究人员。一个等位基因将产生 Kalirin-7 无效。 Kalirin-7 是成人大脑中最常见的亚型，具有单个 Rho GEF 结构域，以独特的 PDZ 结合基序终止。 Kalirin-7 出现在发育后期，并且定位于树突棘。第二个等位基因将产生完全 Kalidn 敲除。两者都将用现有的组织特异性和药物诱导的 Cre 重组酶小鼠进行培育。目标 2 将检查组织特异性 Kalirin 条件性敲除的生化、组织学和发育后果。