AUTHOR=Zhao Lili , Xie Wenhui , Huang Lei , Long Sisi , Wang Puchang 

TITLE=Characterization of the gibberellic oxidase gene SdGA20ox1 in Sophora davidii (Franch.) skeels and interaction protein screening

JOURNAL=Frontiers in Plant Science

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1478854

DOI=10.3389/fpls.2024.1478854

ISSN=1664-462X

ABSTRACT=<p>Gibberellin 20-oxidases (<italic>GA20oxs</italic>) are multifunctional enzymes involved in regulating gibberellin (GA) biosynthesis and controlling plant growth. We identified and characterized the GA20ox1 gene in a plant height mutant of <italic>Sophora davidii</italic>, referred to as <italic>SdGA20ox1</italic>. This gene was expressed in root, stem, and leaf tissues of the adult <italic>S. davidii</italic> plant height mutant, with the highest expression observed in the stem. The expression of <italic>SdGA20ox1</italic> was regulated by various exogenous hormones. Overexpression of <italic>SdGA20ox1</italic> in Arabidopsis resulted in significant elongation of hypocotyl and root length in seedlings, earlier flowering, smaller leaves, reduced leaf chlorophyll content, lighter leaf color, a significant increase in adult plant height, and other phenotypes. Additionally, transgenic plants exhibited a substantial increase in biologically active endogenous GAs (GA1, GA3, and GA4) content, indicating that overexpression of <italic>SdGA20ox1</italic> accelerates plant growth and development. Using a yeast two-hybrid (Y2H) screen, we identified two SdGA20ox1-interacting proteins: the ethylene receptor <italic>EIN4</italic> (11430582) and the <italic>rbcS</italic> (11416005) protein. These interactions suggest a potential regulatory mechanism for <italic>S. davidii</italic> growth. Our findings provide new insights into the role of <italic>SdGA20ox1</italic> and its interacting proteins in regulating the growth and development of <italic>S. davidii</italic>.</p>