Phototropin-and photosynthesis-dependent mitochondrial positioning in Arabidopsis thaliana mesophyll cells^FA  

作　　者：Md Sayeedul Islam Toan Van Nguyen Wataru Sakamoto Shingo Takagi 

机构地区：[1]Department of Biological Sciences,Graduate School of Science,Osaka University,Machikaneyama-cho 1-1,Toyonaka,Osaka 560-0043,Japan [2]Agricultural Genetics Institute,National Key Laboratory for Plant Cell Biotechnology,Pham Van Dong road,Bac Tu Liem district,Ha Noi,Vietnam [3]Institute of Plant Science and Resources,Okayama University,Kurashiki,Okayama 710-0046,Japan

出　　处：《Journal of Integrative Plant Biology》2020年第9期1352-1371,共20页植物学报（英文版）

摘　　要：Mitochondria are frequently observed in the vicinity of chloroplasts in photosynthesizing cells, and this association is considered necessary for their metabolic in-teractions. We previously reported that, in leaf palisade cel s of Arabidopsis thaliana, mitochondria exhibit blue-light-dependent redistribution together with chloroplasts, which conduct accumulation and avoidance responses under the control of blue-light receptor phototropins. In this study, precise motility analyses by fluorescent micro-scopy revealed that the individual mitochondria in palisade cel s, labeled with green fluorescent protein, exhibit typical stop-and-go movement. When exposed to blue light, the velocity of moving mitochondria increased in 30 min, whereas after 4 h, the frequency of stoppage of mi-tochondrial movement markedly increased. Using different mutant plants, we concluded that the presence of both phototropin1 and phototropin2 is necessary for the early acceleration of mitochondrial movement. On the contrary, the late enhancement of stoppage of mitochondrial movement occurs only in the presence of phototropin2 and only when intact photosynthesis takes place. A plasma-membrane ghost assay suggested that the stopped mi-tochondria are firmly adhered to chloroplasts. These re-sults indicate that the physical interaction between mi-tochondria and chloroplasts is cooperatively mediated by phototropin2- and photosynthesis-dependent signals. The present study might add novel regulatory mechanism for light-dependent plant organel e interactions.

关 键 词：tropin ARABIDOPSIS MOVEMENT 

分 类 号：Q945.11[生物学—植物学]