MPK4 Phosphorylation Dynamics and Interacting Proteins in Plant Immunity

• DOI: 10.1021/acs.jproteome.8b00345
• Publication Date: 2019-01-11T14:19:54Z
• Authors: Tong Zhang; Jacqueline D. Sch...; Chuwei Lin; Sisi Geng; Tianyi Ma; Sheldon R. Lawrence; Craig P. Dufresne; Alice C. Harmon; Sixue Chen
• Keywords: Pseudomonas syringae; Jasmonic acid; Immunoprecipitation; Plant Immunity; Jasmonate

Arabidopsis MAP kinase 4 (MPK4) has been proposed to be a negative player in plant immunity, and it is also activated by pathogen-associated molecular patterns (PAMPs), such as flg22. The mechanisms which MPK4 regulates defense remain elusive. In this study, we investigated against bacterial pathogen Pseudomonas syringae pv tomato (Pst) DC3000 when Brassica napus (BnMPK4) overexpressed. We showed an increase resistance suppression of jasmonic acid (JA) signaling the BnMPK4 overexpressing (OE) plants. that OE plants have increased sensitivity flg22-triggered reactive oxygen species (ROS) burst guard cells, resulted enhanced stomatal closure compared wild-type (WT). During flg22 activation, dynamic phosphorylation events within outside conserved TEY activation loop were observed. To elucidate how functions during response, used immunoprecipitation coupled with mass spectrometry (IP-MS) identify interacting proteins absence presence Quantitative proteomic analysis revealed shift MPK4-associated protein network, providing insight into at systems level.