The palea and lemma are floral organ structures unique to grasses;these structures form the hull and directly affect grain size and quality. However, the molecular mechanisms controlling the development of the hull ar...The palea and lemma are floral organ structures unique to grasses;these structures form the hull and directly affect grain size and quality. However, the molecular mechanisms controlling the development of the hull are not well understood. In this study, we characterized the rice(Oryza sativa) abnormal flower and grain1(afg1) mutant, a new allele of OsMADS6. Similar to previously characterized osmads6 alleles, in the afg1 floret, the palea lost its marginal region and acquired the lemma identity. However, in contrast to other osmads6 alleles, the afg1 mutant showed altered grain size and grain quality, with decreased total starch and amylose contents, and increased protein and soluble sugar contents. The analysis of transcriptional activity suggested that AFG1 is a transcriptional activator and may affect grain size by regulating the expression levels of several genes related to cell expansion and proliferation in the afg1 mutant. These results revealed that AFG1 plays an important role in determining palea identity and affecting grain yield and quality in rice.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The palea and lemma are floral organ structures unique to grasses;these structures form the hull and directly affect grain size and quality. However, the molecular mechanisms controlling the development of the hull are not well understood. In this study, we characterized the rice(Oryza sativa) abnormal flower and grain1(afg1) mutant, a new allele of OsMADS6. Similar to previously characterized osmads6 alleles, in the afg1 floret, the palea lost its marginal region and acquired the lemma identity. However, in contrast to other osmads6 alleles, the afg1 mutant showed altered grain size and grain quality, with decreased total starch and amylose contents, and increased protein and soluble sugar contents. The analysis of transcriptional activity suggested that AFG1 is a transcriptional activator and may affect grain size by regulating the expression levels of several genes related to cell expansion and proliferation in the afg1 mutant. These results revealed that AFG1 plays an important role in determining palea identity and affecting grain yield and quality in rice.
