TY  - JOUR
A1  - Song, Yu
A1  - Li, Gang
A1  - Nowak, Jacqueline
A1  - Zhang, Xiaoqing
A1  - Xu, Dongbei
A1  - Yang, Xiujuan
A1  - Huang, Guoqiang
A1  - Liang, Wanqi
A1  - Yang, Litao
A1  - Wang, Canhua
A1  - Bulone, Vincent
A1  - Nikoloski, Zoran
A1  - Hu, Jianping
A1  - Persson, Staffan
A1  - Zhang, Dabing
T1  - The Rice Actin-Binding Protein RMD Regulates Light-Dependent Shoot Gravitropism
JF  - Plant physiology : an international journal devoted to physiology, biochemistry, cellular and molecular biology, biophysics and environmental biology of plants
N2  - Light and gravity are two key determinants in orientating plant stems for proper growth and development. The organization and dynamics of the actin cytoskeleton are essential for cell biology and critically regulated by actin-binding proteins. However, the role of actin cytoskeleton in shoot negative gravitropism remains controversial. In this work, we report that the actin-binding protein Rice Morphology Determinant (RMD) promotes reorganization of the actin cytoskeleton in rice (Oryza sativa) shoots. The changes in actin organization are associated with the ability of the rice shoots to respond to negative gravitropism. Here, light-grown rmd mutant shoots exhibited agravitropic phenotypes. By contrast, etiolated rmd shoots displayed normal negative shoot gravitropism. Furthermore, we show that RMD maintains an actin configuration that promotes statolith mobility in gravisensing endodermal cells, and for proper auxin distribution in light-grown, but not dark-grown, shoots. RMD gene expression is diurnally controlled and directly repressed by the phytochrome-interacting factor-like protein OsPIL16. Consequently, overexpression of OsPIL16 led to gravisensing and actin patterning defects that phenocopied the rmd mutant. Our findings outline a mechanism that links light signaling and gravity perception for straight shoot growth in rice.
Y1  - 2019
U6  - https://doi.org/10.1104/pp.19.00497
SN  - 0032-0889
SN  - 1532-2548
VL  - 181
IS  - 2
SP  - 630
EP  - 644
PB  - American Society of Plant Physiologists
CY  - Rockville
ER  -