NaCl和Na2CO3胁迫下的高粱MAPKs基因家族表达模式

通过在全基因组水平上进行NaCl和Na2CO3胁迫下高粱MAPKs基因表达模式的研究, 探索高粱MAPKs基因在胁迫条件下参与信号传导的机理. 结果
表明, 从高粱基因组中鉴定出16个MAPKs基因, 命名为SbMPKs. 这些SbMPKs在NaCl和Na2CO3胁迫下的表达模式明显不同, 表明中性盐胁迫诱导的信号响应不同于碱性盐. 在NaCl胁迫下, 除了SbMPK13的表达量在12 h时达到最大值外, 所有高粱MAPKs基因在24 h内表达持续上调; 在Na2CO3胁迫下, 只有SbMPK3,SbMPK10和SbMPK13表达上调, 表明这3个基因可能与高粱碱性盐胁迫应答反应有关. 系统发育分析表明, SbMPK13属于C组MAPKs基因, 并且与水稻中受脱落酸（ABA）和盐胁迫诱导表达的OsMAPK2亲缘关系较近, 进一步证实了SbMPK13可能是参与高粱盐胁迫应答的重要调控基因.

Expression Pattern of MAPKs Genes in Sorghum bicolor under Stresses of NaCl and Na2CO3

The availability of sorghum genome makes it possible to perform the genome-wide analysis of the expression profile of MAPKs genes in Sorghum bicolor under the stresses of NaCl and Na2CO3 so as to explore the MAPKs involvement into saline-alkali signaling pathway.The results show that 16 MAPKs genes were dentified from the genome of Sorghum bicolor,namely SbMPKs,and their expression profiles under the stresses of NaCl and Na2CO3 differ from each other significantly.This suggests that neutral salt-induced signal response may differ from that induced by alkaline salt.Under the stress of NaCl,all SbMPKs were up-regulated continuously during 24 h except the SbMPK13 whose expression reached to the maximum at 12 h.Under the stress of Na2CO3,however,only SbMPK3,SbMPK10 and SbMPK13 were up-regulated,implying that SbMPKs are likely responsible specifically for alkaline salt stress in sorghum.Phylogenetic analysis classified SbMPK13 into the C group of MAPKs,which is similar to OsMAPK2 that is responsible to ABA and salt stress in rice,further confirming that it is involved possibly in the regulation of salt stress response genes in sorghum.