OsMPK3 is a TEY-type rice MAPK in Group C and phosphorylates OsbHLH65, a transcription factor binding to the E-box element

Hyun Young Shin, Min Kyoung You, Ji Ung Jeung, Jeong Sheop Shin

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)


Key message: OsMPK3 is a TEY-type rice MAPK belonging to Group C and directly phosphorylates OsbHLH65 in the nucleus. OsMPK3 and OsbHLH65 are induced by biotic stress and defense-related hormones. Mitogen-activated protein kinases (MAPKs) are involved in the majority of signaling pathways that regulate plant development and stress tolerance via the phosphorylation of target molecules. Plant MAPKs are classified into two subtypes, TEY and TDY, according to the TxY (x = E or D) motif in their activation loop, and the TDY motif is unique to plant MAPKs. In rice, 17 MAPKs have been classified into six groups. To date, the functions of many TDY-type rice MAPKs have been characterized, but little is known of the TEY-type MAPKs in Group C and their possible target substrates. In the study reported here, we determined that a TEY-type rice MAPK belonging to subgroup C, named OsMPK3, phosphorylates its substrate OsbHLH65 in the nucleus. Our electrophoresis mobility shift assay results revealed that OsbHLH65 specifically binds to the E-box cis-element, but not to the G-box. Both OsMPK3 and OsbHLH65 were induced by treatments with rice blast (Magnaporthe grisea), brown planthopper (Nilaparvata lugens), and defense-related hormones, such as methyl jasmonic acid and salicylic acid. Our results suggest the possibility that OsMPK3 contributes to the defense signal transduction by phosphorylating the basic helix-loop-helix transcription factor.

Original languageEnglish
Pages (from-to)1343-1353
Number of pages11
JournalPlant Cell Reports
Issue number8
Publication statusPublished - 2014 Aug

Bibliographical note

Funding Information:
Acknowledgments This work was supported by a Grant (2011-0015848) from the National Research Foundation of Korea (NRF) funded by the Ministry of Science and Technology and by a Grant (PJ008160) from the Next-Generation BioGreen 21 Program funded by the Rural Development Administration, Republic of Korea.


  • Basic helix-loop-helix
  • Biotic stress
  • E-box cis-element
  • MAP kinase
  • Magnaporthe grisea
  • Oryza sativa

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Plant Science


Dive into the research topics of 'OsMPK3 is a TEY-type rice MAPK in Group C and phosphorylates OsbHLH65, a transcription factor binding to the E-box element'. Together they form a unique fingerprint.

Cite this