Molecular Mapping Of A Dense Panicle Mutant And Isolate Of Young Panicle Specific Expression Promoters In Rice (Oryza Sativa L.)

Rice (Oryza sativa L.) is one of the most commonly cultivated cereal crops in the world. High-yield breeding has been attracted more and more attentions for decades. Rice is also a significant model for plant genomics study due to its small genome size and relatively short growth-period. In this study, a gene for the panicle mutant was mapped through map-based cloning and 2 specific promoters were isolated from young panicle in rice. The main results are summarized in follows:A dense panicle mutant was obtained after tissue-cultivation from a japonica rice variety Zhonghua 11. As showing dense panicle, the mutant was designated as dp1 (dense panicle 1). Genetic analysis indicated that the mutant is controlled by a semi-dominante gene. A genetic linkage map was constructed using a F2 mapping population derived from a cross between the dp1 mutant and an indica variety Longtefu B. The mutant gene was primarily mapped on chromosome 2, and finally located on a 19kb region between the STS markers STS98 and STS117, where only one ORFs was predicted based on Rice Genome Annotation (http://rice.plantbiology.msu.edu/index.shtml). The cloning of DP1 gene will help to better understanding of the molecular mechanism of panicle architecture and the application of marker-assistant selection in rice breeding.A total of 20 candidate young panicle specific genes were identified from the analyses of rice expressive database inserted their promoters into pCAMBIA1391Z vector and then transformed to callus of Zhonghua 11. Tissues from the transgenic plants obtained for each promoter were stained with GUS at the mature stage to analyze the expression patterns of candidate promoters. Two young panicle specific promoters named as PS01 and PS13 were identified. The analyses for regulative elements of the promoters were conducted from transfering the promoters into pGW vector constructed by GateWay technology into callus of Zhonghua 11.