title: GsAPK, an ABA-activated and calcium-independent SnRK2-type kinase from G. soja, mediates the regulation of plant tolerance to salinity and ABA stress.
abstract: Plant Snf1 (sucrose non-fermenting-1) related protein kinase (SnRK), a subfamily of serine/threonine kinases, has been implicated as a crucial upstream regulator of ABA and osmotic signaling as in many other signaling cascades. In this paper, we have isolated a novel plant specific ABA activated calcium independent protein kinase (GsAPK) from a highly salt tolerant plant, Glycine soja (50109), which is a member of the SnRK2 family. Subcellular localization studies using GFP fusion protein indicated that GsAPK is localized in the plasma membrane. We found that autophosphorylation and Myelin Basis Protein phosphorylation activity of GsAPK is only activated by ABA and the kinase activity also was observed when calcium was replaced by EGTA, suggesting its independence of calcium in enzyme activity. We also found that cold, salinity, drought, and ABA stress alter GsAPK gene transcripts and heterogonous overexpression of GsAPK in Arabidopsis alters plant tolerance to high salinity and ABA stress. In summary, we demonstrated that GsAPK is a Glycine soja ABA activated calcium independent SnRK-type kinase presumably involved in ABA mediated stress signal transduction.
authors.affiliation: Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin, Heilongjiang, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Yang
authors.forename: Wei
authors.initials: W
authors.lastname: Ji
authors.forename: Peng
authors.initials: P
authors.lastname: Gao
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.forename: Hua
authors.initials: H
authors.lastname: Cai
authors.forename: Xi
authors.initials: X
authors.lastname: Bai
authors.forename: Qin
authors.initials: Q
authors.lastname: Chen
authors.forename: Yanming
authors.initials: Y
authors.lastname: Zhu
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism; D018744:DNA, Plant / Q000235:genetics; D007887:Fabaceae / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D009997:Osmotic Pressure; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013025:Glycine max / Q000201:enzymology / Q000235:genetics; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; D018744:DNA, Plant; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D000040:Abscisic Acid; D017346:Protein Serine-Threonine Kinases; D002118:Calcium