NONMUSCLE TROPOMYOSIN ISOFORMS IN DROSOPHILA: IDENTIFICATION AND MODIFICATIONS

果蝇非肌肉原肌球蛋白异构体：鉴定和修饰

• 批准号: 8363835
• 负责人: R DYCHE MULLINS
• 金额: $ 0.29万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8363835
• 关键词: Actins; Actomyosin; Amino Acid Sequence; Animal Model; Cells; Cytokinesis; Drosophila genus; Drosophila melanogaster; Eukaryota; Filopodia; Funding; Genes; Grant; In Vitro; Life; Mass Spectrum Analysis; Microfilaments; Modification; Muscle Contraction; National Center for Research Resources; Peptide Sequence Determination; Principal Investigator; Protein Isoforms; RNA Splicing; Research; Research Infrastructure; Resources; Role; Source; Structure; Tropomyosin; United States National Institutes of Health; Variant; cell type; cost

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Actin makes different structures throughout cells including a branched actin network at the leading edge of motile cells, parallel actin bundles in filopodia, and actomyosin contractile apparatus during cytokinesis. Tropomyosin participates in many of these structures by controlling access to the actin filament. Much is known about tropomyosin's role in muscle contraction, but much less is understood about its role in nonmuscle cells. It is difficult to study tropomyosin in nonmuscle cells because higher eukaryotes can express up to forty different splice variants from four different genes with up to seven isoforms expressed in any one nonmuscle cell type. This isoform diversity makes it difficult to tease out the contributions of each tropomyosin type. The key to solving the mystery of nonmuscle tropomyosin is finding a simple model organism with a minimal number of nonmuscle tropomyosin isoforms that can be individually studied. Drosophila melanogaster seems to be perfect for this task because only one nonmuscle tropomyosin isoform is known to identify the additional nonmuscle isoform(s) have been inconclusive. We believe the UCSF Mass Spectrometry Facility can help us identify the unknown nonmuscle tropomyosin isoforms. We plan to partially isolate native tropomyosin from Drosophila nonmuscle cells (S2 cells), identify the protein sequence using mass spectrometry, and then characterize the isoforms in vitro an in living S2 cells. These studies will help elucidate the role of tropomyosin isoform diversity in nonmuscle cells.

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 肌动蛋白在整个细胞中形成不同的结构，包括运动细胞前沿的分支肌动蛋白网络，丝状伪足中平行的肌动蛋白束，以及胞质分裂时的肌动蛋白收缩装置。原肌球蛋白通过控制肌动蛋白细丝的通路参与其中的许多结构。人们对原肌球蛋白在肌肉收缩中的作用知之甚少，但对其在非肌肉细胞中的作用却知之甚少。在非肌肉细胞中研究原肌球蛋白是很困难的，因为高等真核生物可以表达来自四个不同基因的多达40个不同的剪接变体，在任何一种非肌肉细胞类型中表达多达七种异构体。这种异构体的多样性使得很难梳理出每种原肌球蛋白类型的贡献。解开非肌肉原肌球蛋白之谜的关键是找到一种简单的模式生物，其非肌肉原肌球蛋白亚型的数量最少，可以单独研究。 果蝇似乎是这项任务的完美人选，因为只有一种已知的非肌肉原肌球蛋白亚型能识别额外的非肌肉亚型(S)，目前尚无定论。我们相信加州大学旧金山分校的质谱学设备可以帮助我们识别未知的非肌肉原肌球蛋白亚型。我们计划从果蝇非肌肉细胞(S2细胞)中部分分离天然原肌球蛋白，用质谱仪鉴定其蛋白质序列，然后在体外和活体S2细胞中鉴定其亚型。这些研究将有助于阐明原肌球蛋白异构体在非肌肉细胞中的作用。