The mitogen-activated protein kinase (MAPK) cascades have been validated playing critical roles in diverse aspects of plant biology, from growth and developmental regulation, biotic and abiotic stress responses, to phytohormone signal transduction or responses. A classical MAPK cascade consists of a MAPK kinase kinase (MAPKKK), a MAPK kinase (MAPKK), and a MAPK. From the 75 MAPKKKs, eight MAPKKs, and 15 MAPKs of rice, a number of them have been functionally deciphered. Here, we update recent advances in knowledge of the roles of rice MAPK cascades, including their components and complicated action modes, their diversified functions controlling rice growth and developmental responses, coordinating resistance to biotic and abiotic stress, and conducting phytohormone signal transduction. Moreover, we summarize several complete MAPK cascades that harbor OsMAPKKK-OsMAPKK-OsMAPK, their interaction with different upstream components and their phosphorylation of diverse downstream substrates to fulfill their multiple roles. Furthermore, we state a comparison of networks of rice MAPK cascades from signal transduction crosstalk to the precise selection of downstream substrates. Additionally, we discuss putative concerns for elucidating the underlying molecular mechanisms and molecular functions of rice MAPK cascades in the future.

Rice OsLIC encoding a CCCH zinc finger transcription factor plays an important role in immunity. However, the immune signaling pathways that OsLIC‐involved and the underlying mechanisms that OsLIC‐conferred resistance against pathogens are largely unclear. Here, we show that OsLIC, as a substrate for OsMAPK6, negatively regulates resistance to Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc) by directly suppressing OsWRKY30 transcription. Biochemical assays showed that OsLIC bound to OsWRKY30 promoter and suppressed its transcription. Genetic assays confirmed that the osilc knockout mutants and OsWRKY30‐overexpressing plants exhibited enhanced resistance to Xoo and Xoc, knocking out OsWRKY30 in the oslic mutants attenuated the resistance against bacterial pathogens. OsMAPK6 physically interacted with and phosphorylated OsLIC leading to decreased OsLIC DNA‐binding activity, therefore, overexpression of OsLIC partially suppressed OsMAPK6‐mediated rice resistance. In addition, both OsMAPK6‐phosphorylated activation of OsLIC and phosphorylation‐mimic OsLIC5D had reduced DNA‐binding activity towards OsWRKY30 promoter, thereby promoting OsWRKY30 transcription. Collectively, these results reveal that OsMAPK6‐mediated phosphorylation of OsLIC positively regulates rice resistance to Xoo and Xoc by modulating OsWRKY30 transcription, suggesting that OsMAPK6‐OsLIC‐OsWRKY30 module is an immune signaling pathway in response to the bacterial pathogens.