Rice(Oryza sativa)spikelets are a unique inflorescence structure and their development directly determines grain size and yield.Although many genes related to spikelet development have been reported,the molecular mech...Rice(Oryza sativa)spikelets are a unique inflorescence structure and their development directly determines grain size and yield.Although many genes related to spikelet development have been reported,the molecular mechanisms underlying this process have not been fully elucidated.In this study,we identified a new recessive rice mutant,lacking rudimentary glume 1(lrg1).The lrg1 spikelets only formed one rudimentary glume,which,along with the sterile lemmas,was homeotically transformed into lemma-like organs and acquired lemma identity.The transition from the spikelet to the floral meristem was delayed in the lrg1 mutant,resulting in the formation of an ectopic lemma-like organ between the sterile lemma and the terminal floret.In addition,we found that the abnormal lrg1 grain phenotype resulted from the alteration of cell numbers and the hull size.LRG1 encodes a ZOS4-06-C2H2 zinc-finger protein with the typical EAR motifs,and is expressed in all organs and tissues.LRG1 localizes to the nucleus and can interact with the TOPLESS-RELATED PROTEINs(TPRs)to repress the expressions of their downstream target genes.Taken together,our results reveal that LRG1 plays an important role in the regulation of spikelet organ identity and grain size.展开更多
基金supported by the Zhejiang Natural Science Foundation(LY18C130007)the National Natural Science Foundation of China(91735304)+1 种基金the Central Public-interest Scientific Institution Basal Research Fund of China National Rice Research Institute(2017RG001-4)the National Science and Technology Major Project(2016ZX08009003-003-008)。
文摘Rice(Oryza sativa)spikelets are a unique inflorescence structure and their development directly determines grain size and yield.Although many genes related to spikelet development have been reported,the molecular mechanisms underlying this process have not been fully elucidated.In this study,we identified a new recessive rice mutant,lacking rudimentary glume 1(lrg1).The lrg1 spikelets only formed one rudimentary glume,which,along with the sterile lemmas,was homeotically transformed into lemma-like organs and acquired lemma identity.The transition from the spikelet to the floral meristem was delayed in the lrg1 mutant,resulting in the formation of an ectopic lemma-like organ between the sterile lemma and the terminal floret.In addition,we found that the abnormal lrg1 grain phenotype resulted from the alteration of cell numbers and the hull size.LRG1 encodes a ZOS4-06-C2H2 zinc-finger protein with the typical EAR motifs,and is expressed in all organs and tissues.LRG1 localizes to the nucleus and can interact with the TOPLESS-RELATED PROTEINs(TPRs)to repress the expressions of their downstream target genes.Taken together,our results reveal that LRG1 plays an important role in the regulation of spikelet organ identity and grain size.
