Visual Cell Pigment Cell Interface and Disc Turnover

视觉细胞色素细胞界面和视盘周转

• 批准号: 8383100
• 负责人: JOSEPH C BESHARSE
• 金额: $ 42.52万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 1979
• 资助国家: 美国
• 起止时间: 1979-09-30 至 2016-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8383100
• 关键词: Address; Alleles; Aspartate; Back; Binding; Blindness; Calcium; Carrier Proteins; Cell model; Cells; Cilia; Complex; Coupled; Detection; Development; Disease; Distal; Dynein ATPase; Ethylnitrosourea; Event; Family; Funding; Grant; Guanylate Cyclase; Image; Image Analysis; Induced Mutation; KRP protein; Kinesin; Lead; Length; Life; Light; Link; Maintenance; Mediating; Membrane; Microtubules; Modeling; Molecular; Molecular Motors; Monitor; Motor; Movement; Mus; Mutate; Mutation; Pathway interactions; Pattern; Phosphorylation; Phosphotransferases; Photoreceptors; Phototransduction; Pigments; Play; Plus End of the Microtubule; Proteins; Regulation; Reporting; Retinal; Retinal Cone; Role; Sensory; Serine; Signal Transduction; System; Tail; Testing; Time; Transgenic Model; Up-Regulation; Vertebral column; Vertebrate Photoreceptors; Visual; Walking; Work; Zebrafish; base; calmodulin-dependent protein kinase II; cell motility; cellular imaging; cilium biogenesis; insight; loss of function; loss of function mutation; macromolecule; member; mutant; neuronal cell body; relating to nervous system; retinal rods; trafficking; voltage gated channel

DESCRIPTION (provided by applicant): Phototransduction in the photoreceptor outer segment (OS), a sensory cilium, is among the best- understood neural signaling systems, but the molecular details and regulation of assembly of the OS remain unclear. During the past grant period we focused on intraflagellar transport (IFT), a conserved pathway mediated by two kinesin 2 family motors, kinesin II and KIF17. Photoreceptors coordinate renewal and turnover of photosensitive discs according to light-dark cycles, and diurnal changes in intracellular calcium regulate the activity of kinases like CaMKII. This proposal is based on our recent finding that that phosphorylation of KIF17 at a conserved serine in its tail domain facilitates its association with IFT machinery. Furthermore, mutation of this serine in the zebrafish sequence to an aspartate results in entry into the OS and increased OS turnover through disc shedding, and KIF17 abundance and phosphorylation state are regulated in a diurnal pattern. These findings lead to the hypothesis that KIF17 mediated IFT is regulated in relationship to OS turnover and influences turnover through regulation of the dynamics of the distal ciliary axoneme at the OS tip. Aim 1 will analyze the KIF17 loss of function mutations in both zebrafish and mice to assess the overall importance of this motor in photoreceptors compared to other cilium types. Aim 2 will use coordinated analysis of OS turnover, axoneme organization and KIF17 dynamics in zebrafish using transgenic models to test the hypothesis a KIF17 regulates the distal axoneme dynamics, which in turn is coupled to OS turnover. Aim 3 will utilize real time imaging in isolated zebrafish photoreceptors to study KIF17 movement in the distal OS segment and its relationship to IFT motility. Completion of these aims will provide insight into fundamental regulatory functions of OS segment assembly that are directly relevant photoreceptor diseases.

描述（由申请人提供）：光感受器外节（OS）（一种感觉纤毛）中的光转导是最了解的神经信号系统之一，但 OS 组装的分子细节和调节仍不清楚。在过去的资助期间，我们重点研究鞭毛内运输（IFT），这是一种由两个驱动蛋白 2 家族马达（驱动蛋白 II 和 KIF17）介导的保守途径。光感受器根据明暗周期协调光敏盘的更新和周转，细胞内钙的昼夜变化调节 CaMKII 等激酶的活性。该提议基于我们最近的发现，即 KIF17 尾部结构域保守丝氨酸的磷酸化促进其与 IFT 机制的关联。此外，斑马鱼序列中的丝氨酸突变为天冬氨酸会导致进入 OS 并通过椎间盘脱落增加 OS 更新，并且 KIF17 丰度和磷酸化状态以昼夜模式进行调节。这些发现得出这样的假设：KIF17 介导的 IFT 受到与 OS 周转相关的调节，并通过调节 OS 尖端远端纤毛轴丝的动态来影响周转。目标 1 将分析斑马鱼和小鼠中的 KIF17 功能丧失突变，以评估与其他纤毛类型相比该运动在光感受器中的总体重要性。目标 2 将使用转基因模型对斑马鱼的 OS 周转、轴丝组织和 KIF17 动态进行协调分析，以检验 KIF17 调节远端轴丝动态的假设，而远端轴丝动态又与 OS 周转相关。目标 3 将利用离体斑马鱼光感受器的实时成像来研究远端 OS 段中的 KIF17 运动及其与 IFT 运动的关系。完成这些目标将有助于深入了解与光感受器疾病直接相关的 OS 片段组装的基本调节功能。