gsapk, an aba-activated and calcium-independent snrk2-type kinase from g. soja, mediates the regulation of plant tolerance to salinity and aba stressgsapk,aba-activated和calcium-independent snrk2-type激酶从野生大豆,介导植物耐盐度和aba的监管压力.pdfVIP

GsAPK, an ABA-Activated and Calcium-Independent SnRK2-Type Kinase from G. soja, Mediates the Regulation of Plant Tolerance to Salinity and ABA Stress 1,2. 1. 1 1 1 1 3 1 Liang Yang , Wei Ji , Peng Gao , Yong Li , Hua Cai , Xi Bai , Qin Chen , Yanming Zhu * 1 Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin, Heilongjiang, China, 2 Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agricultural and Forestry University, Fuzhou, Fujian, China, 3 Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, Alberta, Canada 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 presuma