摘要
Green-revertible albino is a novel type of chlorophyll deficiency in rice （Oryza sativa L.）, which is helpful for further research in chlorophyll synthesis and chloroplast development to illuminate their molecular mechanism. In the previous study, we had reported a single recessive gene, gra（t）, controlling this trait on the long arm of chromosome 2. In this paper, we mapped the gra（t） gene using 1,936 recessive individuals with albino phenotype in the F2 population derived from the cross between themo-photoperiod-sensitive genic male-sterile （T/PGMS） line Pei＇ai 64S and the spontaneous mutant Qiufeng M. Eventually, it was located to a confined region of 42.4 kb flanked by two microsatellite markers RM2-97 and RM13553. Based on the annotation results of RiceGAAS system, 11 open reading frames （ORFs） were predicted in this region. Among them, ORF6 was the most possible gene related to chloroplast development, which encoded the chloroplast protein synthesis elongation factor Tu in rice. Therefore, we designated it as the candidate gene of gra（t）. Sequence analysis indicated that only one base substitution C to T occurred in the coding region, which caused a missense mutation （Thr to Ile） in gra（t） mutant. These results are very valuable for further study on gra（t） gene.
Green-revertible albino is a novel type of chlorophyll deficiency in rice （Oryza sativa L.）, which is helpful for further research in chlorophyll synthesis and chloroplast development to illuminate their molecular mechanism. In the previous study, we had reported a single recessive gene, gra（t）, controlling this trait on the long arm of chromosome 2. In this paper, we mapped the gra（t） gene using 1,936 recessive individuals with albino phenotype in the F2 population derived from the cross between themo-photoperiod-sensitive genic male-sterile （T/PGMS） line Pei＇ai 64S and the spontaneous mutant Qiufeng M. Eventually, it was located to a confined region of 42.4 kb flanked by two microsatellite markers RM2-97 and RM13553. Based on the annotation results of RiceGAAS system, 11 open reading frames （ORFs） were predicted in this region. Among them, ORF6 was the most possible gene related to chloroplast development, which encoded the chloroplast protein synthesis elongation factor Tu in rice. Therefore, we designated it as the candidate gene of gra（t）. Sequence analysis indicated that only one base substitution C to T occurred in the coding region, which caused a missense mutation （Thr to Ile） in gra（t） mutant. These results are very valuable for further study on gra（t） gene.
基金
supported by the National High-tech Research and Development Program of China (863 Program) (No. 2006AA100101)
the National Science and Technology Support Program (No. 2006BAD01A01-5)
Special Program for Rice Scientific Research of Ministry of Agriculture (No. nyhyzx 07-001-006)
Super Rice Breeding and Demonstration Program of Ministry of Agriculture, and Jiangsu Selfinnovation Fund for Agricultural Science and Technology (No. CX[08]603).
