Myosin XI Is Required for Actin-Associated Movement of Plastid Stromules

作     者：Senthil Kumar A. Natesan James A. Sullivan John C. Gray 

作者机构：Department of Plant Sciences University of Cambridge Downing Street Cambridge CB2 3EA UK Present address: Sir William Dunn School of Pathology University of Oxford South Parks Road Oxford OX1 3RE UK Present address: School of Biological and Chemical Sciences Queen Mary University of London Mile End Road London E1 4NS UK 

出 版 物：《Molecular Plant》 (分子植物（英文版）)

年 卷 期：2009年第2卷第6期

页      面：1262-1272页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 080802[工学-电力系统及其自动化] 0808[工学-电气工程] 07[理学] 08[工学] 0817[工学-化学工程与技术] 

基　　金：Biotechnology and Biological Sciences Research Council, BBSRC Gates Cambridge Trust 

主　　题：Chloroplast biology cytoskeleton organelle biogenesis/function tobacco. 

摘      要：Stromules are highly dynamic stroma-filled tubules extending from the surface of plastids and occasionally interconnecting individual plastids, allowing the movement of complex biological molecules between the interconnected plastids. Experiments with inhibitors of cytoskeleton assembly have indicated the involvement of an actin-based system in stromule movement. However, the motor protein associated with the system had not been identified. Here, we present direct evidence that myosin XI is involved in the formation and movement of stromules in tobacco leaves. Application of 2,3-butanedione 2-monoxime, an inhibitor of myosin ATPase activity, resulted in the loss of stromules from tobacco leaf epidermal cells. Transient RNA interference of myosin XI in leaves of Nicotiana benthamiana also resulted in the loss of stromules from epidermal cells, without any effect on transcripts for actin or myosin VIII. Transient expression of a GFP- tagged myosin XI tail domain in tobacco leaf epidermal cells showed that the fusion protein localized to the chloroplast envelope, as well as to mitochondria and other organelles. Our findings identify myosin XI as a key protein involved in the formation and movement of stromules.