SHORT-ROOT paralogs mediate feedforward regulation of D-type cyclin to promote nodule formation in soybean
Chunhua Wang, Meng Li, Yang Zhao, Nengsong Liang, Haiyang Li, Pengxue Li, Liling Yang, Mengyuan Xu, Xinxin Bian, Mengxue Wang, Shasha Wu, Shasha Wu, Xufang Niu, Mengyao Wang, Xinxin Li, Yi Sang, Wentao Dong, Ertao Wang, Kimberly L. Gallagher, Shuang Wu, Shuang Wu
Abstract
is positively associated with cortical cell division and nodulation. Knockdown of GmSHR5 inhibits cell division in outer cortical layers during nodulation. Knockdown of both paralogs disrupts the cell division throughout the cortex, resulting in poorly organized nodule primordia with delayed vascular tissue formation. GmSHR4/5 function by enhancing cytokinin signaling and activating early nodulin genes. Interestingly, D-type cyclins act downstream of GmSHR4/5, and GmSHR4/5 form a feedforward loop regulating D-type cyclins. Overexpression of D-type cyclins in soybean roots also enhanced nodulation. Collectively, we conclude that the GmSHR4/5-mediated pathway represents a vital module that triggers cytokinin signaling and activates D-type cyclins during nodulation in soybean.