title: Identification and expression analysis of the Glycine max CYP707A gene family in response to drought and salt stresses.
abstract: OBJECTIVE
  Abscisic acid (ABA) plays crucial roles in plants' responses to abiotic stresses. ABA 8'-hydroxylation controlled by CYP707A genes has been well studied in Arabidopsis and rice, but not in legumes. The aims of the present study were to identify and functionally analyse the soybean CYP707A gene family, and to explore their expression patterns under dehydration and salt stresses.
  
  
  METHODS
  A complementation experiment was employed to verify the function of soybean CYP707A1a in ABA catabolism. Genomic and cDNA sequences of other soybean CYP707A genes were isolated from the Phytozome database based on soybean CYP707A1a. The structure and phylogenetic relationship of this gene family was further analysed. The expression patterns of soybean CYP707A genes under dehydration and salt stress were analysed via quantitative real-time PCR.
  
  
  RESULTS
  Over-expression of GmCYP707A1a in the atcyp707a2 T-DNA insertion mutant decreased its sensitivity to ABA, indicating that GmCYP707A1a indeed functions as an ABA 8'-hydroxylase in higher plants. The soybean genome contains ten CYP707A genes. Gene structure and phylogenetic analysis showed high conservation of ten GmCYP707A genes to the other CYP707A genes from monocots and dicots. Seed imbibition induced expression of A1a, A1b, A2a, A2b, A2c, A3a and A5 in embryo, and expression of A1a, A1b, A2a and A2b in cotyledon. Dehydration induced expression of A1a, A1b, A2b, A2c, A3a, A3b, A4a, A4b and A5 both in roots and in leaves, whereas rehydration stimulated transcription of A2a, A2b, A3b, A4a and A5 in roots, and only A3b and A5 in leaves. Expression of all soybean CYP707A genes was induced either by short- or by long-term salt stress.
  
  
  CONCLUSIONS
  The first biological evidence is provided that GmCYP7071a encodes an ABA 8'-hydroxylase through transgenic studies. Ten soybean GmCYP707A genes were identified, most of them expressed in multiple soybean tissues, and were induced by imbibition, dehydration and salinity.
authors: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Root Biology Center, South China Agricultural University, Guangzhou 510642, China.
authors: Yan
authors: Y
authors: Zheng
authors: Yingyi
authors: Y
authors: Huang
authors: Weihao
authors: W
authors: Xian
authors: Jinxiang
authors: J
authors: Wang
authors: Hong
authors: H
authors: Liao
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D017343:Genes, Plant; D010940:Plant Proteins; D030821:Plants, Genetically Modified; D054712:Salinity; D012965:Sodium Chloride / Q000494:pharmacology*; D013025:Glycine max / Q000235:genetics* / Q000378:metabolism*; D013312:Stress, Physiological / Q000235:genetics; D014867:Water / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D014867:Water; D012965:Sodium Chloride; D003577:Cytochrome P-450 Enzyme System; C107203:abscisic acid 8'-hydroxylase