title: Over-Expression of GmGIa-Regulated Soybean miR172a Confers Early Flowering in Transgenic Arabidopsis thaliana.
abstract: Flowering is a pivotal event in the life cycle of plants. miR172 has been widely confirmed to play critical roles in flowering time control by regulating its target gene expression in Arabidopsis. However, the role of its counterpart in soybean remains largely unclear. In the present study, we found that the gma-miR172a was regulated by a GIGANTEA ortholog, GmGIa, in soybean through miRNA metabolism. The expression analysis revealed that gma-miR172a has a pattern of diurnal rhythm expression and its abundance increased rapidly as plants grew until the initiation of flowering phase in soybean. One target gene of gma-miR172a, Glyma03g33470, was predicted and verified using a modified RLM 5'-RACE (RNA ligase-mediated rapid amplification of 5' cDNA ends) assay. Overexpression of gma-miR172a exhibited an early flowering phenotype and the expression of FT, AP1 and LFY were simultaneously increased in gma-miR172a-transgenic Arabidopsis plants, suggesting that the early flowering phenotype was associated with up-regulation of these genes. The overexpression of the gma-miR172a-resistant version of Glyma03g33470 weakened early flowering phenotype in the toe1 mutant of Arabidopsis. Taken together, our results suggested that gma-miR172a played an important role in GmGIa-mediated flowering by repressing Glyma03g33470, which in turn increased the expression of FT, AP1 and LFY to promote flowering in soybean.
authors.affiliation: Key Laboratory of Soybean Biology in Chinese Education Ministry (Northeastern Key Laboratory of Soybean Biology and Genetics &amp; Breeding in Chinese Ministry of Agriculture), Northeast Agricultural University, Harbin 150030, China. wangtao6559@126.com.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: Key Laboratory of Soybean Biology in Chinese Education Ministry (Northeastern Key Laboratory of Soybean Biology and Genetics &amp; Breeding in Chinese Ministry of Agriculture), Northeast Agricultural University, Harbin 150030, China. sunmingyangphy@163.com.
authors.forename: Ming-Yang
authors.initials: MY
authors.lastname: Sun
authors.affiliation: Key Laboratory of Soybean Biology in Chinese Education Ministry (Northeastern Key Laboratory of Soybean Biology and Genetics &amp; Breeding in Chinese Ministry of Agriculture), Northeast Agricultural University, Harbin 150030, China. cedarwxs@163.com.
authors.forename: Xue-Song
authors.initials: XS
authors.lastname: Wang
authors.affiliation: Key Laboratory of Soybean Biology in Chinese Education Ministry (Northeastern Key Laboratory of Soybean Biology and Genetics &amp; Breeding in Chinese Ministry of Agriculture), Northeast Agricultural University, Harbin 150030, China. wenbinli@neau.edu.cn.
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: Li
authors.affiliation: Key Laboratory of Soybean Biology in Chinese Education Ministry (Northeastern Key Laboratory of Soybean Biology and Genetics &amp; Breeding in Chinese Ministry of Agriculture), Northeast Agricultural University, Harbin 150030, China. yongguangli@neau.edu.cn.
authors.forename: Yong-Guang
authors.initials: YG
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism; D001483:Base Sequence; D002940:Circadian Rhythm / Q000502:physiology; D035264:Flowers / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D030262:Soybean Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism; D013025:Glycine max / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D035683:MicroRNAs; D030262:Soybean Proteins
keywords: Arabidopsis thaliana; flowering; gma-miR172a; soybean (Glycine max L. Merr.)