AUTHOR=Huang Yuan , Jiao Yang , Yang Sha , Mao Dandan , Wang Feng , Chen Liangbi , Liang Manzhong 

TITLE=SiNCED1, a 9-cis-epoxycarotenoid dioxygenase gene in Setaria italica, is involved in drought tolerance and seed germination in transgenic Arabidopsis

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1121809

DOI=10.3389/fpls.2023.1121809

ISSN=1664-462X

ABSTRACT=<p>Foxtail millet (<italic>Setaria italica</italic> L.) is a vital cereal food crop with promising development and utilization potential because of its outstanding ability to resist drought stress. However, the molecular mechanisms underlying its drought stress resistance remain unclear. In this study, we aimed to elucidate the molecular function of a 9-cis-epoxycarotenoid dioxygenase gene, <italic>SiNCED1</italic>, in the drought stress response of foxtail millet. Expression pattern analysis showed that <italic>SiNCED1</italic> expression was significantly induced by abscisic acid (ABA), osmotic stress, and salt stress. Furthermore, ectopic overexpression of <italic>SiNCED1</italic> could enhance drought stress resistance by elevating endogenous ABA levels and promoting stomatal closure. Transcript analysis indicated that <italic>SiNCED1</italic> modulated ABA-related stress responsive gene expression. In addition, we found that ectopic expression of <italic>SiNCED1</italic> delayed seed germination under normal and abiotic stress conditions. Taken together, our results show that <italic>SiNCED1</italic> plays a positive role in the drought tolerance and seed dormancy of foxtail millet by modulating ABA biosynthesis. In conclusion, this study revealed that <italic>SiNCED1</italic> is an important candidate gene for the improvement of drought stress tolerance in foxtail millet and could be beneficial in the breeding and investigation of drought tolerance in other agronomic crops.</p>