摘 要 ：为了进一步探讨植物MAPKs（mitogen activated protein kinases）在植物防卫中的作用，该研究从不结球白菜抗病品种‘苏州青’中克隆到一个抗核盘菌（Sclerotinia sclerotiorum）相关基因，命名为BcMPK4(DDBJ登录号AB557751)。该基因核苷酸序列全长1 334 bp，编码373个氨基酸，与已克隆的MPK4基因有不同程度的相似性。系统进化树分析表明，该基因在不同物种之间具有保守性。基因组DNA杂交表明，BcMPK4可能属于一个较小的多基因家族，属组成型表达。实时定量PCR检测表明，核盘菌能够诱导不结球白菜BcMPK4基因的转录表达；BcMPK4基因在不结球白菜叶片中的表达特征说明它可能参与寄主对核盘菌的抗性。
Abstract:Plant mitogen activated protein kinases (MAPKs) have been implicated in plant defense as a new component of the defense signaling pathways.In this study,a Sclerotinia sclerotiorum cDNA clone in Brassica campestris ssp.chinensis cv.Duanbaigeng was isolated and characterized.The gene was designated as BcMPK4 (DDBJ accession number AB557751),which contains 1 334 bp nucleotide and encodes 373 amino acids.BcMPK4 had different homology score of amino acid compared with MPK4 genes of other plants.Phylogenetic analysis revealed the evolutionary conservation of these proteins among diverse species.Southern blotting hybridization with genomic DNA showed that BcMPK4 belonged to a multigene family.Real time quantitative PCR analysis revealed that BcMPK4 transcript was increased after inoculated with S.sclerotiorum.Expression characterization of BcMPK4 in Brassica campestris ssp.chinensis indicated that it might be involved in host resistance against S.sclerotiorum.