Plant height and tillering are crucial factors determining rice plant architecture and influencing rice grain production. In this study, rnulti-tillering dwarf1 （mtdl）, a stable multi-tiller and dwarf mutant, was sc...Plant height and tillering are crucial factors determining rice plant architecture and influencing rice grain production. In this study, rnulti-tillering dwarf1 （mtdl）, a stable multi-tiller and dwarf mutant, was screened from the ethylmethane sulfonate-treated japonica rice variety Wuyunging7. Compared with the wild type, mtdl mutant exhibited pleiotropic phenotypes, including dwarf- ism, more tillers, brittle culms and delayed heading date. By employing map-based cloning strategy, the gene MTD1 was finally mapped to an approximately 66-kb region on the short arm of chromosome 9. Sequencing results showed that the gene LOCOsO9g02650 （BC12） in mtdl mutant had a single nucleotide substitution （G to A）, which gen- erated a premature translation stop. Over-expressing MTD1/BC12 coding sequ（nce rescued all the phenotypes of mtdl mutants including plant height and tillers, which confirms that BC12 is the mutated gene in mtdl mutant. Quantitative reverse tran,-eription-PCR analysis showed that MTDI/BCI2 could negatively regulate the expression of MONOCULM 1, IDEAL PLANT ARCHITECTURE1 and Tillering and Dwarf 1, and control rice tillering. Remark- ably, a-amylase activity analysis and gibberellic acid （GA） treatment showed that the dwarf phenotype of mtdl mutant was dependent on GA biosynthesis pathway. These results facilitated to further uncover the molecular mechanism of the growth and development in rice.展开更多
基金supported by the National Natural Science Foundation of China (31401464, 31201183)Zhejiang Provincial Natural Science Foundation of China (Y3110194, LY16C130001)+1 种基金China Postdoctoral Science Foundation (2014M561108)the Open Foundation from Zhejiang Provincial Top Key Discipline of Biology (KFJJ2014006)
文摘Plant height and tillering are crucial factors determining rice plant architecture and influencing rice grain production. In this study, rnulti-tillering dwarf1 （mtdl）, a stable multi-tiller and dwarf mutant, was screened from the ethylmethane sulfonate-treated japonica rice variety Wuyunging7. Compared with the wild type, mtdl mutant exhibited pleiotropic phenotypes, including dwarf- ism, more tillers, brittle culms and delayed heading date. By employing map-based cloning strategy, the gene MTD1 was finally mapped to an approximately 66-kb region on the short arm of chromosome 9. Sequencing results showed that the gene LOCOsO9g02650 （BC12） in mtdl mutant had a single nucleotide substitution （G to A）, which gen- erated a premature translation stop. Over-expressing MTD1/BC12 coding sequ（nce rescued all the phenotypes of mtdl mutants including plant height and tillers, which confirms that BC12 is the mutated gene in mtdl mutant. Quantitative reverse tran,-eription-PCR analysis showed that MTDI/BCI2 could negatively regulate the expression of MONOCULM 1, IDEAL PLANT ARCHITECTURE1 and Tillering and Dwarf 1, and control rice tillering. Remark- ably, a-amylase activity analysis and gibberellic acid （GA） treatment showed that the dwarf phenotype of mtdl mutant was dependent on GA biosynthesis pathway. These results facilitated to further uncover the molecular mechanism of the growth and development in rice.
