Regulation of Myosin V Interaction with Cargo

肌球蛋白 V 与货物相互作用的调节

• 批准号: 8496065
• 负责人: Lois S Weisman
• 金额: $ 38.07万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8496065
• 关键词: Actins; Adaptor Signaling Protein; Affect; Animals; Behavior; Binding; Binding Sites; Cell division; Cell physiology; Complex; Cytomegalovirus Infections; Defect; Deposition; Destinations; Diarrhea; Dimerization; Disease; Dominant-Negative Mutation; Employee Strikes; Eukaryota; Fluorescence; Genes; Goals; Golgi Apparatus; Griscelli Syndrome; Hallmark Cell; Human; In Vitro; Individual; Intracellular Transport; Lead; Life; Link; Location; MLPH gene; MYO5A gene; Measures; Melanosomes; Microtubules; Morphology; Motor; Movement; Mutation; Myosin ATPase; Myosin Type V; Neurologic; Organelles; Peptides; Pharmaceutical Preparations; Phosphorylation Site; Phosphotransferases; Physiology; Pigmentation physiologic function; Play; Point Mutation; Positioning Attribute; Protein Binding; Proteins; Regulation; Resolution; Role; Saccharomyces cerevisiae; Secretory Vesicles; Sirolimus; Site; Specific qualifier value; Structure; Surface; Tacrolimus Binding Proteins; Tail; Testing; Time; To specify; Vacuole; Vesicle; Yeasts; base; cell type; cellular microvillus; design; dimer; human disease; in vivo; infancy; insight; monomer; mutant; nervous system disorder; novel; organelle movement; public health relevance; rab GTP-Binding Proteins; small molecule

DESCRIPTION (provided by applicant): Organelle movement is a hallmark of cell division and cellular differentiation. In every cell-type, the localization, number and morphology of each type of organelle is modified to achieve specific cellular functions. Long-range movement of organelles occurs on microtubules, while positioning of organelles at their final destination relies on actin-based motors. Myosin V motors play a critical role in actin based movement in all eukaryotes, and disruption of myosin V function causes disease in humans. For example, partial defects in myosin Va based transport cause Griscelli's syndrome, characterized by neurological and pigmentation defects. Partial defects in myosin Vb cause microvillus inclusion disease, characterized by infantile, life threatening diarrhea. Currently there are no effective drug-based treatments for either disease. Determination of how myosin V based transport is achieved may provide important new insights into treating theseetach from cargoes at the correct time and place. The globular tail domain (GTD) of myosin V attaches to its cargoes through organelle-specific adaptor proteins. Regulation of the GTD and adaptor proteins contributes to specifying cargo attachment. We determined a high-resolution structure of the GTD of Myo2, a Saccharomyces cerevisiae myosin V motor, and identified two distinct cargo binding regions; one required for binding to the yeast vacuole, the other required for binding to secretory vesicles. We found that the vacuole binding site interacts with a novel protein, Vac17. The secretory vesicle binding site attaches directly to a Rab GTPase. Importantly, we found that the Rab GTPase binding site is conserved in human myosin Va and myosin Vb. Thus, our studies in yeast revealed the Rab GTPase binding site on human myosin V motors. The general conservation of the cargo binding domains of yeast Myo2 and human myosin Va and Vb, and the fact that Rab GTPases act directly to attach carns. Our major goals are to: 1) Determine whether the binding of an individual Myo2 adaptor protein enhances or inhibits binding of other adaptor proteins. 2) Identify and characterize proteins that regulate the attachment of Rab GTPases to the GTD of Myo2. 3) Determine mechanisms that regulate the detachment of myosin V from cargoes.

描述（由申请人提供）：细胞器运动是细胞分裂和细胞分化的标志。在每个细胞类型中，每种细胞器的定位，数和形态都经过修改以实现特定的细胞功能。细胞器的远程运动发生在微管上，而细胞器在最终目的地的定位依赖于基于肌动蛋白的电动机。肌球蛋白V电动机在所有真核生物的基于肌动蛋白的运动中起着至关重要的作用，并且肌球蛋白V功能的破坏会导致人类疾病。例如，基于肌球蛋白的转运的部分缺陷导致Griscelli综合征，其特征是神经系统和色素沉着缺陷。肌球蛋白VB的部分缺陷会引起微伏属疾病，其特征是婴儿腹泻。目前，尚无对任何一种疾病的有效基于药物的治疗方法。确定如何实现基于肌球蛋白V的运输可能会在正确的时间和地点从货物中处理这些eThetach的重要新见解。肌球蛋白V的球状尾部结构域（GTD）通过细胞器特异性衔接蛋白连接到其货物上。 GTD和衔接蛋白的调节有助于指定货物附着。我们确定了Myo2的GTD的高分辨率结构，酿酒酵母肌球蛋白V运动，并确定了两个不同的货物结合区。一种与酵母液泡结合所需的，另一个与分泌囊泡结合所需。我们发现液泡结合位点与新型蛋白质Vac17相互作用。分泌囊泡结合位点直接附着在RAB GTPase上。重要的是，我们发现RAB GTPase结合位点在人肌球蛋白VA和肌球蛋白VB中保守。因此，我们在酵母中的研究揭示了人肌球蛋白V电机上的RAB GTPase结合位点。酵母肌2和人肌球蛋白VA和VB的货物结合结构域的一般保护以及Rab GTPases直接作用以附加Carns的事实。我们的主要目标是：1）确定单个MyO2适配器蛋白的结合是否增强或抑制其他衔接蛋白的结合。 2）识别和表征调节RAB GTPases附着在Myo2的GTD上的蛋白质。 3）确定调节肌球蛋白V与货物的脱离的机制。