Yangxuan Liu1,2, Ting Pan1,2, Yuying Tang1,2, Yong Zhuang1,2, Zhijian Liu1,2, Penghui Li1,2, Hui Li1,2,3, Weizao Huang1,2, Shengbin Tu1,2, Guangjun Ren4, Tao Wang1,2, Songhu Wang5,6,7,8. 1. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China. 2. University of Chinese Academy of Sciences, Beijing, 100049, China. 3. Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw, 05282, Myanmar. 4. Crop Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, 610066, People's Republic of China. 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China. wangsh1@cib.ac.cn. 6. University of Chinese Academy of Sciences, Beijing, 100049, China. wangsh1@cib.ac.cn. 7. Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw, 05282, Myanmar. wangsh1@cib.ac.cn. 8. School of Horticulture, Anhui Agricultural University, Hefei, 230036, China. wangsh1@cib.ac.cn.
Abstract
BACKGROUND: Light provides the energy for photosynthesis and determines plant morphogenesis and development. Low light compromises photosynthetic efficiency and leads to crop yield loss. It remains unknown how rice responds to low light stress at a proteomic level. RESULTS: In this study, the quantitative proteomic analysis with isobaric tags for relative and absolute quantitation (iTRAQ) was used and 1221 differentially expressed proteins (DEPs) were identified from wild type rice plants grown in control or low light condition (17% light intensity of control), respectively. Bioinformatic analysis of DEPs indicated low light remarkably affects the abundance of chloroplastic proteins. Specifically, the proteins involved in carbon fixation (Calvin cycle), electron transport, and ATPase complex are severely downregulated under low light. Furthermore, overexpression of the downregulated gene encoding rice β subunit of glyceraldehyde-3-phosphate dehydrogenase (OsGAPB), an enzyme in Calvin cycle, significantly increased the CO2 assimilation rate, chlorophyll content and fresh weight under low light conditions but have no obvious effect on rice growth and development under control light. CONCLUSION: Our results revealed that low light stress on vegetative stage of rice inhibits photosynthesis possibly by decreasing the photosynthetic proteins and OsGAPB gene is a good candidate for manipulating rice tolerance to low light stress.
BACKGROUND: Light provides the energy for photosynthesis and determines plant morphogenesis and development. Low light compromises photosynthetic efficiency and leads to crop yield loss. It remains unknown how rice responds to low light stress at a proteomic level. RESULTS: In this study, the quantitative proteomic analysis with isobaric tags for relative and absolute quantitation (iTRAQ) was used and 1221 differentially expressed proteins (DEPs) were identified from wild type rice plants grown in control or low light condition (17% light intensity of control), respectively. Bioinformatic analysis of DEPs indicated low light remarkably affects the abundance of chloroplastic proteins. Specifically, the proteins involved in carbon fixation (Calvin cycle), electron transport, and ATPase complex are severely downregulated under low light. Furthermore, overexpression of the downregulated gene encoding rice β subunit of glyceraldehyde-3-phosphate dehydrogenase (OsGAPB), an enzyme in Calvin cycle, significantly increased the CO2 assimilation rate, chlorophyll content and fresh weight under low light conditions but have no obvious effect on rice growth and development under control light. CONCLUSION: Our results revealed that low light stress on vegetative stage of rice inhibits photosynthesis possibly by decreasing the photosynthetic proteins and OsGAPB gene is a good candidate for manipulating rice tolerance to low light stress.