Functional Analysis Of OsSCL30b With Multiple Stress Responses And Cloning Of OsCP12 In Rice

Rice is one of the main food crops for human beings.It is widely planted in cultivated land all over the world.At present,China has been a big consumer of rice.In recent years.Various abiotic stresses,such as low temperature,drought and high salt,affect rice throughout its growth period,determining its yield and quality,and eventually bringing serious economic and social crisis.In the long-term evolution process,rice has been equipped with various strategies to quickly sense and respond to external environmental fluctuations.Therefore,it is especially important to study and use the adaptability of rice to respond to external stresses,improve the resistance of rice to stress,and cultivate new rice varieties with strong tolerance.It is particularly important to ensure grain yield under adverse circumstances.In our laboratory,a multi-stress-induced Os SCL30 b rice shear factor protein was cloned.Then,using yeast two-hybrid technology,Os SCL30 b was selected as a bait protein from a rice c DNA library and an OsCP12Calvin cycle regulatory protein interacting with it was cloned.The main findings are as follows:1.The OsSCL30b(Os12g38430)is located on chromosome 12 of Nihonbori,with a c DNA size of 1250 bp,no introns,and a CDS of 792 bp.It encodes a protein consisting of 263 amino acid residues.The predicted molecular weight of the protein is approximately 30.19 k D,and the isoelectric point is about 10.9.Analysis of the protein domain revealed that the N-terminus contained an RNA recognition motif domain and the C-terminus was a serine/arginine(S/R)-rich repeat.The promoter region contains cis-acting elements such as LTR,ABRE,TGA-element,TGACG-motif and CGTCA-motif,SP1.2.The subcellular localization results directly observed from rice root cells showed that Os SCL30 b was localized on the nucleus.The results of rice seedling tolerance test and recovery test showed that the overexpression of Os SCL30 b attenuated the low temperature,drought and salt resistance of transgenic rice.The grain length of Os SCL30 b overexpressing transgenic rice is greater than Nipponbare,and the grain width,grain thickness,number of tillers and plant height are all smaller than Nipponbare.3.The Os CP12(Os03g19380)gene is located on rice chromosome 3 of Nihonbori,with a c DNA size of 622 bp,no introns,and a CDS of 396 bp.It encodes a protein consisting of 131 amino acid residues.The predicted molecular weight is 13.90 k D,and the isoelectric point is about 4.65.Analysis of the protein domain revealed a CP12 domain at the C-terminus.The promoter of this gene contains cis-regulatory elements such as ABRE,TCA-element,TGA-element,TGACG-motif,and GCTCA-motif.4.The results of quantitative qRT-PCR showed that OsCP12was positively regulated by low temperature,high temperature and drought,and negatively regulated by salt and ABA.Among them,drought had the greatest effect on the expression of Os CP12.GUS activity test results showed that OsCP12expression was detected in roots,stems,leaves,ears and anthers.The results of rice seedling tolerance test and recovery test showed that the overexpression of OsCP12enhanced the low temperature resistance of transgenic rice.