title: OsMADS1Represses microRNA172 in Elongation of Palea/Lemma Development in Rice.
abstract: Specification of floral organ identity is critical for the establishment of floral morphology and inflorescence architecture. Although multiple genes are involved in the regulation of floral organogenesis, our understanding of the underlying regulating network is still fragmentary. MADs-box genes are principle members in the ABCDE model that characterized floral organs.OsMADS1specifies the determinacy of spikelet meristem and lemma/palea identity in rice. However, the pathway through whichOsMADS1regulates floral organs remains elusive; here, we identified the microRNA172 (miR172) family as possible regulators downstream ofOsMADS1. Genetic study revealed that overexpression of each miR172 gene resulted in elongated lemma/palea and indeterminacy of the floret, which resemble the phenotype ofosmads1mutant. On the contrary, overexpression of each targetAPETALA2(AP2) genes resulted in shortened palea/lemma. Expression level and specificity of miR172 was greatly influenced byOsMADS1, as revealed by Northern blot analysis andIn situhybridization. Genetically,AP2-3andAP2-2over expression rescued the elongation and inconsistent development of the lemma/palea in OsMADS1RNAi transgenic plants. Our results suggested that in rice,OsMADS1and miR172s/AP2s formed a regulatory network involved in floral organ development, particularly the elongation of the lemma and the palea.
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences Shanghai, China.
authors.forename: Zhengyan
authors.initials: Z
authors.lastname: Dai
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences Shanghai, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences Shanghai, China.
authors.forename: Mulan
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences Shanghai, China.
authors.forename: Xuexia
authors.initials: X
authors.lastname: Miao
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences Shanghai, China.
authors.forename: Zhenying
authors.initials: Z
authors.lastname: Shi
keywords: OsMADS1; determinacy; floral organs; lemma; miR172; palea