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.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的主要研究者可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 肌动蛋白在整个细胞中形成不同的结构，包括运动细胞前缘的分支肌动蛋白网络、丝状伪足中的平行肌动蛋白束以及胞质分裂期间的肌动球蛋白收缩装置。 原肌球蛋白通过控制肌动蛋白丝的通路参与许多这些结构。 人们对原肌球蛋白在肌肉收缩中的作用了解甚多，但对其在非肌肉细胞中的作用了解甚少。 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种不同基因的多达四十种不同的剪接变体，并且在任何一种非肌肉细胞类型中表达多达七种亚型。 这种异构体的多样性使得很难弄清楚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型生物体，其具有最少数量的可单独研究的非肌肉原肌球蛋白亚型。 黑腹果蝇似乎非常适合这项任务，因为已知只有一种非肌肉原肌球蛋白亚型可以识别其他非肌肉亚型，但尚无定论。 我们相信加州大学旧金山分校质谱设备可以帮助我们鉴定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，使用质谱法鉴定蛋白质序列，然后在体外和活体 S2 细胞中表征亚型。 这些研究将有助于阐明原肌球蛋白亚型多样性在非肌肉细胞中的作用。