title: Expression of an apoplast-localized BURP-domain protein from soybean (GmRD22) enhances tolerance towards abiotic stress.
abstract: The BURP-domain protein family comprises a diverse group of plant-specific proteins that share a conserved BURP domain at the C terminus. However, there have been only limited studies on the functions and subcellular localization of these proteins. Members of the RD22-like subfamily are postulated to associate with stress responses due to the stress-inducible nature of some RD22-like genes. In this report, we used different transgenic systems (cells and in planta) to show that the expression of a stress-inducible RD22-like protein from soybean (GmRD22) can alleviate salinity and osmotic stress. We also performed detailed microscopic studies using both fusion proteins and immuno-electron microscopic techniques to demonstrate the apoplast localization of GmRD22, for which the BURP domain is a critical determinant of the subcellular localization. The apoplastic GmRD22 interacts with a cell wall peroxidase and the ectopic expression of GmRD22 in both transgenic Arabidopsis thaliana and transgenic rice resulted in increased lignin production when subjected to salinity stress. It is possible that GmRD22 regulates cell wall peroxidases and hence strengthens cell wall integrity under such stress conditions.
authors.affiliation: State Key Laboratory of Agrobiotechnology & School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Wang
authors.forename: Liang
authors.initials: L
authors.lastname: Zhou
authors.forename: Yaping
authors.initials: Y
authors.lastname: Fu
authors.forename: Ming-Yan
authors.initials: MY
authors.lastname: Cheung
authors.forename: Fuk-Ling
authors.initials: FL
authors.lastname: Wong
authors.forename: Tsui-Hung
authors.initials: TH
authors.lastname: Phang
authors.forename: Zongxiu
authors.initials: Z
authors.lastname: Sun
authors.forename: Hon-Ming
authors.initials: HM
authors.lastname: Lam
mesh_terms: D020816:Amino Acid Motifs; D017360:Arabidopsis / Q000235:genetics; D003001:Cloning, Molecular; D012275:Oryza / Q000235:genetics; D009997:Osmotic Pressure; D009195:Peroxidase / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D030821:Plants, Genetically Modified; D013025:Glycine max / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D013312:Stress, Physiological; D014026:Nicotiana / Q000235:genetics
chemical_list: D010940:Plant Proteins; D009195:Peroxidase