Identification And Protokaryotic Expression Of PBZ1and Mutant Screening Of Dongxiang Wild Rice

Dongxiang wild rice is the most north of wild rice in the world with strong cold resistance which can survive winter. It is the unique and precious wild rice resources of China with lots of excellent biological properties such as high ability of tillering, drought and disease resistance; Screening mutant of Dongxiang wild rice for illustrating molecular mechanisms of beneficial traits and identification of the favorable genes are of great significance in understanding mechanisms of environment stresses such cold-, drought-, and salt-stress and development of new high-quality rice variety.In this study, the full-length cDN A library of Dongxiang wild rice was constructed by the SMART technology. The PBZ1gene with477bp was cloned and identified from the cDNA Library, which encodes158amino-acid protein with a molecular weight of22kD. Bioinformatics analysis revealed that the PBZ1gene and protein from Dongxiang wild rice showed more than99%homology with those of cultivated rices.The whole PBZ1gene was amplified by PCR, and ligated with pET28a(+) to construct the recombinant plasmid of pET28a(+)-PBZ1. The recombinant PBZ1protein was expressed in E.coli BL21induced by IPTG. The SDS-PAGE detection showed that the recombinant PBZ1protein was expressed successfully. In the former study, PBZ1is a kind of pathogen related protein, which plays a key role in responses to disease resistance and abiotic stress in rice. This study laid the foundation for the further research about the function of PBZ1protein.In our study, The mutants of Dongxiang wild rice were screened by treating with1%EMS in stage of seed germinating. Two of262Mo generation plants showed obvious mutant phenotypes. Compared with those of the wild type, the mutants had erect plant, fewer tillering, shorter awn, thicker stalk. The genes of TAC1and PROG1were cloned from wild type and mutants, but the amino acid sequences of the two genes are identical, revealing that the two proteins sequences were not related to mutant phenotypes. This study provided basic materials and also laid the foundation for the further research about the molecular mechanism in controlling rice traits.