title: Lever arm extension of myosin VI is unnecessary for the adjacent binding state.
abstract: Myosin VI is a processive myosin that has a unique stepping motion, which includes three kinds of steps: a large forward step, a small forward step and a backward step. Recently, we proposed the parallel lever arms model to explain the adjacent binding state, which is necessary for the unique motion. In this model, both lever arms are directed the same direction. However, experimental evidence has not refuted the possibility that the adjacent binding state emerges from myosin VI folding its lever arm extension (LAE). To clarify this issue, we constructed a myosin VI/V chimera that replaces the myosin VI LAE with the IQ3-6 domains of the myosin V lever arm, which cannot fold, and performed single molecule imaging. Our chimera showed the same stepping patterns as myosin VI, indicating the LAE is not responsible for the adjacent binding state.
authors: Graduate School of Frontier Biosciences, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan; Quantitative Biology Center (QBiC), RIKEN, Furuedai, Suita, Osaka 565-0874, Japan.
authors: Keigo
authors: K
authors: Ikezaki
authors: Graduate School of Frontier Biosciences, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Tomotaka
authors: T
authors: Komori
authors: Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors: Yoshiyuki
authors: Y
authors: Arai
authors: Graduate School of Frontier Biosciences, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan; Quantitative Biology Center (QBiC), RIKEN, Furuedai, Suita, Osaka 565-0874, Japan; Center for Information and Neural Networks (CiNet), Yamadaoka, Suita, Osaka 565-0871, Japan; WPI, Immunology Frontier Research Center, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Toshio
authors: T
authors: Yanagida
keywords: genetic engineering; molecular functions; molecular motors; molecular structures; single molecule imaging