Overexpression of OsSAP16 Regulates Photosynthesis and the Expression of a Broad Range of Stress Response Genes in Rice (Oryza sativa L.).
This study set out to identify and characterize transcription factors regulating photosynthesis in rice. Screening populations of rice T-DNA activation lines led to the identification of a T-DNA mutant with an increase in intrinsic water use efficiency (iWUE) under well-watered conditions. Flanking sequence analysis showed that the T-DNA construct was located upstream of LOC_Os07g38240 (OsSAP16) encoding for a stress-associated protein (SAP). A second mutant identified with activation in the same gene exhibited the same phenotype; expression of OsSAP16 was shown to be enhanced in both lines. There were no differences in stomatal development or morphology in either of these mutants, although overexpression of OsSAP16 reduced stomatal conductance. This phenotype limited CO2 uptake and the rate of photosynthesis, which resulted in the accumulation of less biomass in the two mutants. Whole transcriptome analysis showed that overexpression of OsSAP16 led to global changes in gene expression consistent with the function of zinc-finger transcription factors. These results show that the gene is involved in modulating the response of rice to drought stress through regulation of the expression of a set of stress-associated genes.
National Key Laboratory of Crop Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei province, 430070, China.
Fei
F
Wang
C4 Rice Center, International Rice Research Institute, Los Baños, Philippines.
Robert A
RA
Coe
C4 Rice Center, International Rice Research Institute, Los Baños, Philippines.
Shanta
S
Karki
C4 Rice Center, International Rice Research Institute, Los Baños, Philippines.
Samart
S
Wanchana
C4 Rice Center, International Rice Research Institute, Los Baños, Philippines.
Vivek
V
Thakur
Crop and Environmental Science Division, International Rice Research Institute, Los Baños, Philippines.
Amelia
A
Henry
C4 Rice Center, International Rice Research Institute, Los Baños, Philippines.
Hsiang-Chun
HC
Lin
National Key Laboratory of Crop Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei province, 430070, China.
Jianliang
J
Huang
National Key Laboratory of Crop Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei province, 430070, China.
Shaobing
S
Peng
C4 Rice Center, International Rice Research Institute, Los Baños, Philippines.
William Paul
WP
Quick
D018533:Biomass; D002245:Carbon Dioxide / Q000378:metabolism; D020869:Gene Expression Profiling / Q000379:methods; D018506:Gene Expression Regulation, Plant; D063990:Gene Ontology; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D010641:Phenotype; D010788:Photosynthesis / Q000235:genetics* / Q000502:physiology; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D010940:Plant Proteins / Q000145:classification / Q000235:genetics*; D054046:Plant Stomata / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013312:Stress, Physiological / Q000235:genetics*; D014867:Water / Q000378:metabolism
D010940:Plant Proteins; D014867:Water; D002245:Carbon Dioxide