Premium
A bHLH transcription factor, MYC2, imparts salt intolerance by regulating proline biosynthesis in Arabidopsis
Author(s) -
Verma Deepanjali,
Jalmi Siddhi Kashinath,
Bhagat Prakash Kumar,
Verma Neetu,
Sinha Alok Krishna
Publication year - 2020
Publication title -
the febs journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.981
H-Index - 204
eISSN - 1742-4658
pISSN - 1742-464X
DOI - 10.1111/febs.15157
Subject(s) - transcription factor , proline , arabidopsis , biochemistry , protein kinase a , kinase , microbiology and biotechnology , biology , biosynthesis , abiotic stress , mapk/erk pathway , chemistry , enzyme , gene , amino acid , mutant
MYC2, a bHLH TF, acts as regulatory hub within several signaling pathways by integration of various endogenous and exogenous signals which shape plant growth and development. However, its involvement in salt stress regulation is still elusive. This study has deciphered a novel role of MYC2 in imparting salt stress intolerance by regulating delta1 ‐pyrroline‐5‐carboxylate synthase1 (P5CS1) gene and hence proline synthesis. P5CS1 is a rate‐limiting enzyme in the biosynthesis of proline. Y‐1‐H and EMSA studies confirmed the binding of MYC2 with the 5′UTR region of P5CS1 . Transcript and biochemical studies have revealed MYC2 as a negative regulator of proline biosynthesis. Proline is necessary for imparting tolerance toward abiotic stress; however, its overaccumulation is toxic for the plants. Hence, studying the regulation of proline biosynthesis is requisite to understand the mechanism of stress tolerance. We have also studied that MYC2 is regulated by mitogen‐activated protein kinase (MAPK) cascade mitogen‐activated protein kinase kinase 3‐MPK6 and vice versa. Altogether, this study demonstrates salt stress‐mediated activation of MYC2 by MAPK cascade, regulating proline biosynthesis and thus salt stress.