title: GmFLD, a soybean homolog of the autonomous pathway gene FLOWERING LOCUS D, promotes flowering in Arabidopsis thaliana.
abstract: BACKGROUND
  Flowering at an appropriate time is crucial for seed maturity and reproductive success in all flowering plants. Soybean (Glycine max) is a typical short day plant, and both photoperiod and autonomous pathway genes exist in soybean genome. However, little is known about the functions of soybean autonomous pathway genes. In this article, we examined the functions of a soybean homolog of the autonomous pathway gene FLOWERING LOCUS D (FLD), GmFLD in the flowering transition of A. thaliana.
  
  
  RESULTS
  In soybean, GmFLD is highly expressed in expanded cotyledons of seedlings, roots, and young pods. However, the expression levels are low in leaves and shoot apexes. Expression of GmFLD in A. thaliana (Col) resulted in early flowering of the transgenic plants, and rescued the late flowering phenotype of the A. thaliana fld mutant. In GmFLD transgenic plants (Col or fld background), the FLC (FLOWERING LOCUS C) transcript levels decreased whereas the floral integrators, FT and SOC1, were up-regulated when compared with the corresponding non-transgenic genotypes. Furthermore, chromatin immuno-precipitation analysis showed that in the transgenic rescued lines (fld background), the levels of both tri-methylation of histone H3 Lys-4 and acetylation of H4 decreased significantly around the transcriptional start site of FLC. This is consistent with the function of GmFLD as a histone demethylase.
  
  
  CONCLUSIONS
  Our results suggest that GmFLD is a functional ortholog of the Arabidopsis FLD and may play an important role in the regulation of chromatin state in soybean. The present data provides the first evidence for the evolutionary conservation of the components in the autonomous pathway in soybean.
authors.forename: Qin
authors.initials: Q
authors.lastname: Hu
authors.forename: Ye
authors.initials: Y
authors.lastname: Jin
authors.forename: Huazhong
authors.initials: H
authors.lastname: Shi
authors.affiliation: Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, People's Republic of China. yangwn@mail.ccnu.edu.cn.
authors.forename: Wannian
authors.initials: W
authors.lastname: Yang
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D035264:Flowers / Q000235:genetics* / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D013025:Glycine max / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins