Identification of Thermo-Sensitive Chloroplast Development Gene <i>TSCD5</i> Required for Rice Chloroplast Development under High Temperature
Shenglong Yang,
Guonan Fang,
Banpu Ruan,
Anpeng Zhang,
Yun Zhou,
Guangji Ye,
Wang Su,
Heng Guo,
Jian Wang,
Zhenyu Gao
Affiliations
Shenglong Yang
Key Laboratory of Qinghai-Tibet Plateau Biotechnology Ministry of Education, Qinghai Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
Guonan Fang
Key Laboratory of Qinghai-Tibet Plateau Biotechnology Ministry of Education, Qinghai Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
Banpu Ruan
China National Rice Research Institute, Hangzhou 310006, China
Anpeng Zhang
China National Rice Research Institute, Hangzhou 310006, China
Yun Zhou
Key Laboratory of Qinghai-Tibet Plateau Biotechnology Ministry of Education, Qinghai Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
Guangji Ye
Key Laboratory of Qinghai-Tibet Plateau Biotechnology Ministry of Education, Qinghai Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
Wang Su
Key Laboratory of Qinghai-Tibet Plateau Biotechnology Ministry of Education, Qinghai Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
Heng Guo
Key Laboratory of Qinghai-Tibet Plateau Biotechnology Ministry of Education, Qinghai Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
Jian Wang
Key Laboratory of Qinghai-Tibet Plateau Biotechnology Ministry of Education, Qinghai Academy of Agriculture and Forestry Sciences, Qinghai University, Xining 810016, China
Zhenyu Gao
China National Rice Research Institute, Hangzhou 310006, China
Chloroplasts are critical organelles for photosynthesis and play significant roles in plant growth and metabolism. High temperature is one of abiotic stresses affecting the growth and development of plants, involving chlorophyll biosynthesis and chloroplast development. It is well known that the methyl erythritol 4-phosphate (MEP) pathway is vital to photosynthesis and plant growth, and 1-deoxy-D-xylulose-5-phosphate synthase (DXS) is the enzyme that catalyze the first step of the MEP pathway. Although DXS has been widely studied in microbes and plants, no DXS gene has been identified in rice. Here, a novel thermo-sensitive chlorophyll-deficient 5 (tscd5) mutant was isolated in rice with decreased chlorophyll contents, impaired chloroplasts, and albino leaves at high temperature (35 °C). Fine mapping and DNA sequencing of TSCD5 found a missense mutation (G to A) in the sixth exon of LOC_Os05g33840 in tscd5. The TSCD5 gene encodes a 1-deoxy-D-xylulose-5-phosphate synthase 1 (OsDXS1) localized in chloroplast. Complementation tests and overexpression assay demonstrated that the mutation in LOC_Os05g33840 caused the tscd5 phenotype. qRT-PCR of TSCD5 showed it was constitutively expressed in all tissues, and its transcript amounts were reduced in tscd5 under high temperature. Here, TSCD5 is verified to be crucial to chloroplast development under high temperature in rice, which may facilitate the elucidation of the molecular mechanisms which underlie acclimation to high temperature stress in plants.
