AUTHOR=Cui Yanchun , Wang Manling , Zhou Huina , Li Mingjuan , Huang Lifang , Yin Xuming , Zhao Guoqiang , Lin Fucheng , Xia Xinjie , Xu Guoyun 

TITLE=OsSGL, a Novel DUF1645 Domain-Containing Protein, Confers Enhanced Drought Tolerance in Transgenic Rice and Arabidopsis

JOURNAL=Frontiers in Plant Science

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.02001

DOI=10.3389/fpls.2016.02001

ISSN=1664-462X

ABSTRACT=<p>Drought is a major environmental factor that limits plant growth and crop productivity. Genetic engineering is an effective approach to improve drought tolerance in various crops, including rice (<italic>Oryza sativa</italic>). Functional characterization of relevant genes is a prerequisite when identifying candidates for such improvements. We investigated OsSGL (<italic>Oryza sativa</italic><underline>S</underline>tress tolerance and <underline>G</underline>rain <underline>L</underline>ength), a novel DUF1645 domain-containing protein from rice. <italic>OsSGL</italic> was up-regulated by multiple stresses and localized to the nucleus. Transgenic plants over-expressing or hetero-expressing <italic>OsSGL</italic> conferred significantly improved drought tolerance in transgenic rice and <italic>Arabidopsis thaliana</italic>, respectively. The overexpressing plants accumulated higher levels of proline and soluble sugars but lower malondialdehyde (MDA) contents under osmotic stress. Our RNA-sequencing data demonstrated that several stress-responsive genes were significantly altered in transgenic rice plants. We unexpectedly observed that those overexpressing rice plants also had extensive root systems, perhaps due to the altered transcript levels of auxin- and cytokinin-associated genes. These results suggest that the mechanism by which <italic>OsSGL</italic> confers enhanced drought tolerance is due to the modulated expression of stress-responsive genes, higher accumulations of osmolytes, and enlarged root systems.</p>