Understanding the regulation mechanism of root meristem development by RGF1 peptide
Stem cell niche is maintained by the signaling networks of the peptide hormone, Root Meristem Growth Factor 1 (RGF1). Recently, I discovered a series of signaling events following RGF1 action. There are three major discoveries.1.The discovery of the downstream pathways of RGF1 peptideThe RGF1-receptor pathway controlled expression of a novel transcription factor RGF1 INDUCIBLE TRANSCRIPTION FACTOR 1 (RITF1), which leads to the redistributions of reactive oxygen species (ROS) along the developmental zones of the Arabidopsis root. These ROS redistributions resulted in an increase in root meristem size. 2.The discovery of enhancement of PLETHORA2 (PLT2) protein stability by ROSAlteration of the distribution of ROS signals by RGF1 enhanced the stability of the PLT2 protein, a master regulator of root stem cells. The broader localization of the PLT2 protein resulted in producing larger meristem.3.The discovery of RITF1 to control distributions of ROSRGF1 treatment could not modulate ROS distributions and root meristem size in the ritf1 mutant. Further, similarly to RGF1treatment, overexpression of RITF1 altered ROS distributions and increased the root meristem size. These demonstrated that a novel transcription factor RITF1 is a primary regulator to control ROS distribution downstream of the RGF1 pathway.Co-researchers:Xinwei Han, Philip Benfey