title: Comprehensive analysis of differentially expressed rice actin depolymerizing factor gene family and heterologous overexpression of OsADF3 confers Arabidopsis Thaliana drought tolerance.
abstract: BACKGROUND
  Actin depolymerizing factors (ADFs) are small actin-binding proteins. Many higher-plant ADFs has been known to involve in plant growth, development and pathogen defense. However, in rice the temporal and spatial expression of OsADF gene family and their relationship with abiotic stresses tolerance is still unknown.
  
  
  RESULTS
  Here we reported the first comprehensive gene expression profile analysis of OsADF gene family. The OsADF genes showed distinct and overlapping gene expression patterns at different growth stages, tissues and abiotic stresses. We also demonstrated that both OsADF1 and OsADF3 proteins were localized in the nucleus. OsADF1 and OsADF3 were preferentially expressed in vascular tissues. Under ABA or abiotic stress treatments, OsADF3::GUS activity was enhanced in lateral roots and root tips. Ectopically overexpressed OsADF3 conferred the mannitol- and drought-stress tolerance of transgenic Arabidopsis seedlings by increasing germination rate, primary root length and survival. Several drought-tolerance responsive genes (RD22, ABF4, DREB2A, RD29A, PIP1; 4 and PIP2; 6) were upregulated in transgenic Arabidopsis under drought stress.
  
  
  CONCLUSIONS
  These results suggested that OsADF gene family may participate in plant abiotic stresses response or tolerance and would facilitate functional validation of other OsADF genes.
authors.affiliation: Department of Agronomy, National Taiwan University, No, 1, Section 4, Roosevelt Road, Taipei 106, Taiwan, Republic of China. menchi@ntu.edu.tw.
authors.forename: Ya-Chen
authors.initials: YC
authors.lastname: Huang
authors.forename: Wen-Lii
authors.initials: WL
authors.lastname: Huang
authors.forename: Chwan-Yang
authors.initials: CY
authors.lastname: Hong
authors.forename: Hur-Shen
authors.initials: HS
authors.lastname: Lur
authors.forename: Men-Chi
authors.initials: MC
authors.lastname: Chang