Abstract
A SNF1-related kinase 2 homolog (LeSRK2C) cDNA was isolated from tomato Micro-Tom (Lycopersicon esculentum Mill.). LeSRK2C has a kinase domain in the amino terminal domain and an acidic and hydrophobic amino acid-rich region in the carboxyl terminus. LeSRK2C mRNA is expressed in leaves, flowers and fruits but not in roots. A recombinant LeSRK2C expressed in E. coli cells phosphorylated myelin basic protein but not histone H1. LeSRK2C is detected mainly in leaves, but not in flowers, fruits nor roots by immunoblot using an anti-LeSRK2C specific antiserum. Transient expression assay of LeSRK2C by agroinfiltration method demonstrated that LeSRK2C is stimulated strongly by chilling stress and by NaCl stress. These observation shows that LeSRK2C has an important role in stress signaling of tomato leaves in response to salt and chilling stress.
