Physiological and transcriptome analysis of indica rice 'MH86' overexpressing OsSPL14

Abstract

overexpression transgenic plants showed shorter growth period, 2 6 short-narrow flag leaves, and thick-green leaves. Transcript profile, abscisic acid 2 7 (ABA) and gibberellin acid (GA 3 ) level, and culm composition also changed 2 8 obviously. Abstract 3 0 OsSPL14, identified as IDEAL PLANT ARCHITECTURE1 (IPA1) or WEALTHY 3 1 FARMER'S PANICLE (WFP) gene, plays a critical role in regulating rice plant 3 2architecture. Here, the study showed that OsSPL14-overexpression transgenic rice 3 3 plants had shorter growth period, short-narrow flag leaves, and thick-green leaves. 3 4 Compared with wild type plant 'MH86', transgenic plants had higher chlorophyll a 3 5 (Ca), chlorophyll b (Cb) and carotenoid (Cx) content at both seedling and maturity 3 6 stage. Meanwhile, transcriptome analysis identified 473 up-regulated and 103 3 7 down-regulated genes in transgenic plant. The expression of differentially expressed 3 8 genes (DEGs) involved in carotenoid biosynthesis, abscisic acid (ABA) metabolism 3 9 and lignin biosynthesis increased significantly. Most of DEGs participated in "plant 4 0 hormone signal transduction" and "starch and sucrose metabolism" are also 4 1 up-regulated in transgenic plant. In addition, there were higher levels of ABA and 4 2 gibberellin acid (GA 3 ) in OsSPL14-overexpression transgenic plants. Moreover, the 4 3 content of culm lignin, cellulose, silicon and potassium all increased dramatically. 4 4 Thus, these results demonstrate that overexpression of OsSPL14 has influence on leaf 4 5 development, hormone level and culm composition in rice, which provide more 4 6 insight into understanding the function of OsSPL14. 4 7 4 8