PROG1 acts upstream of LAZY1 to regulate rice tiller angle as a repressor
Han Zhang,
Xiang Li,
Dajun Sang,
Linzhou Huang,
Yuqi Song,
Mengchen Du,
Jiajia Cao,
Wenguang Wang
Affiliations
Han Zhang
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, Shandong, China
Xiang Li
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, Shandong, China
Dajun Sang
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
Linzhou Huang
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
Yuqi Song
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, Shandong, China
Mengchen Du
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, Shandong, China
Jiajia Cao
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, Shandong, China
Wenguang Wang
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, Shandong, China; Corresponding author.
Rice tiller angle, as a component of plant architecture, affects rice grain yield via plant density. However, the molecular mechanism underlying rice tiller angle remains elusive. We report that the key domestication gene PROSTRATE GROWTH 1 (PROG1) controls rice tiller angle by regulating shoot gravitropism and LAZY1 (LA1)-mediated asymmetric distribution of auxin. Acting as a transcriptional repressor, PROG1 negatively regulates the expression of LA1 in light-grown rice seedlings. Overexpression of LA1 partially rescued the larger tiller angle of the PROG1 complementation transgenic plant (prog1-D). Double-mutant analysis showed that PROG1 acts upstream of LA1 to regulate shoot gravitropism and tiller angle. Mutation of Suppressors of lazy1 (SOL1), encoding DWARF3 (D3) acting in the strigolactone signal pathway, suppressed the large tiller angle of prog1-D by rescuing the transcription of LA1. The discovery of a light-sensitive PROG1-LA1 transcription regulatory module controlling rice shoot gravitropism and tiller angle sheds light on the genetic control of rice tiller angle.
