THRUMIN1 is a light-regulated actin-bundling protein involved in chloroplast motility

摘要: Chloroplast movement in response to changing light conditions optimizes photosynthetic absorption. This repositioning is stimulated by blue perceived via the phototropin photoreceptors and transduced actin cytoskeleton. Some actin-based motility systems use filament reorganizations rather than myosin-based translocations. Recent research favors hypothesis that chloroplast driven reorganization at plasma membrane, but no proteins affecting movements have been shown associate with both membrane filaments vivo. Here we identified THRUMIN1 as a critical link between photoreceptor activity actin-dependent movements. bundles filamentous vitro, it localizes displays light- phototropin-dependent localization microfilaments These results suggest phototropin-induced bundling important for movement. A mammalian homolog of THRUMIN1, GRXCR1, has implicated auditory responses hair cell stereocilla development regulator architecture. Studies will help elucidate function this family eukaryotic proteins.