AUTHOR=Lim Junsub , Lim Chae Woo , Lee Sung Chul 

TITLE=Role of pepper MYB transcription factor CaDIM1 in regulation of the drought response

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1028392

DOI=10.3389/fpls.2022.1028392

ISSN=1664-462X

ABSTRACT=<p>Abscisic acid (ABA) is a major phytohormone that plays important roles in stress responses, including regulation of gene expression and stomatal closure. Regulation of gene expression by transcription factors is a key cellular process for initiating defense responses to biotic and abiotic stresses. Here, using pepper (<italic>Capsicum annuum</italic>) leaves, we identified the MYB transcription factor <italic>CaDIM1</italic> (<italic>Capsicum annuum</italic> Drought <underline>I</underline>nduced MYB 1), which was highly induced by ABA and drought stress. CaDIM1 has an MYB domain in the N-terminal region and an acidic domain in the C-terminal region, which are responsible for recognition and transactivation of the target gene, respectively. Compared to control plants, <italic>CaDIM1</italic>-silenced pepper plants displayed ABA-insensitive and drought-sensitive phenotypes with reduced expression of stress-responsive genes. On the other hand, overexpression of <italic>CaDIM1</italic> in Arabidopsis exhibited the opposite phenotypes of <italic>CaDIM1</italic>-silenced pepper plants, accompanied by enhanced ABA sensitivity and drought tolerance. Taken together, we demonstrate that CaDIM1 functions as a positive regulator of the drought-stress response <italic>via</italic> modulating ABA-mediated gene expression.</p>