761 / 2019-05-30 20:58:19

Traversing the pathways crosslinking Auxin Signaling and MAP Kinase Cascade

MAPK, Auxin signaling, post translational modification

全体主题 > Signal Transduction

Auxins regulate diverse cellular and developmental responses in plants. Auxin signaling involve TRANSPORT INHIBTOR RESPONSE/AUXIN-BINDING F-BOX PROTEIN (TIR1/AFB) which is suggested to be an auxin receptor, the Aux/IAA transcriptional repressors, and the auxin response factors (ARFs) which directly regulates the transcription of auxin responsive genes. The Aux/IAAs are a family of extremely short-lived nuclear proteins. Aux/IAA genes are induced rapidly by auxin and are found throughout the higher plants. There are 31 members of Aux/IAA in Rice (Oryza sativa) and 29 in Arabidopsis (Arabidopsis thaliana). The MAP kinases comprise of a linear cascade of three consecutively acting protein kinases, namely MAPKs, MAPKKs and MAPKKKs mediating sequential phosphorylation reactions. The existence of a cross-talk between auxin and MAPK cascade has been elusive so far. Here we report a plausible cross-talk between auxin signaling and MAPK cascade. Expression analysis studies suggested significant regulation of Auxin responsive genes in both Arabidopsis and in Rice MAPK mutant lines. Further in-vitro kinase assay showed these auxin responsive genes are targets of MAPK. Further characterization of identified auxin signalling components with MAPKs will be discussed during presentation. Our study indicates a strong crosstalk of MAPK and auxin responsive genes during auxin signalling pathway.