AUTHOR=Truong Hai An , Lee Seokjin , Trịnh Cao Son , Lee Won Je , Chung Eui-Hwan , Hong Suk-Whan , Lee Hojoung 

TITLE=Overexpression of the HDA15 Gene Confers Resistance to Salt Stress by the Induction of NCED3, an ABA Biosynthesis Enzyme

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.640443

DOI=10.3389/fpls.2021.640443

ISSN=1664-462X

ABSTRACT=<p>Salt stress constitutes a major form of abiotic stress in plants. Histone modification plays an important role in stress tolerance, with particular reference to salt stress resistance. In the current study, we found that HDA15 overexpression confers salt stress resistance to young seedling stages of transgenic plants. Furthermore, salt stress induces <italic>HDA15</italic> overexpression. Transcription levels of stress-responsive genes were increased in transgenic plants overexpressing <italic>HDA15</italic> (<italic>HDA15 OE</italic>). <italic>NCED3</italic>, an abscisic acid (ABA) biosynthetic gene, which is highly upregulated in <italic>HDA15</italic> transgenic plants, enhanced the accumulation of ABA, which promotes adaptation to salt stress. ABA homeostasis in <italic>HDA15 OE</italic> plants is maintained by the induction of CYP707As, which optimize endogenous ABA levels. Lastly, we found that the double-mutant <italic>HDA15 OE/hy5 ko</italic> plants are sensitive to salt stress, indicating that interaction between HDA15 and ELONGATED HYPOCOTYL 5 (HY5) is crucial to salt stress tolerance shown by <italic>HDA15 OE</italic> plants. Thus, our findings indicate that <italic>HDA15</italic> is crucial to salt stress tolerance in <italic>Arabidopsis</italic>.</p>