DRN facilitates WUS transcriptional regulatory activity by chromatin remodeling to regulate shoot stem cell homeostasis in Arabidopsis

WUSCHEL: The essential regulator of the Arabidopsis shoot Apical Meristem

Plant longevity depends on reservoirs of slowly proliferating stem cells, where a reduced rate of division is essential for maintaining DNA integrity. Aboveground stem cells are localized in the central zone of the shoot meristems, whose size is controlled by the transcription factor WUS. This review focuses on the mechanism of WUS function and the regulation of its expression. WUS maintains the central zone's size by controlling the hormones such as cytokinins. It forms complexes with various transcription factors and can act as a repressor and an activator of gene transcription. Cytokinins define WUS spatial expression relative to the meristem surface, while EPFL signaling limits WUS radial expansion. CLV3 signaling modulates WUS expression levels within the boundaries set by cytokinin and EPFLs. A significant overlap of WUS and CLV3 expression in the L3 layer suggests that autocrine signaling by CLV3 may play a central role in regulating WUS expression.

Research Progress of CLE and Its Prospects in Woody Plants

The peptide ligands of the CLAVATA3/EMBRYO SURROUNDING REGION-RELATED (CLE) family have been previously identified as essential signals for both short- and long-distance communication in plants, particularly during stem cell homeostasis, cell fate determination, and growth and development. To date, most studies on the CLE family have focused on model plants and especially those involving stem and apical meristems. Relatively little is known about the role of CLE peptides in tall trees and other plant meristems. In this review, we summarize the role of CLE genes in regulating plant Root Apical Meristem (RAM), Shoot Apical Meristem (SAM), Procambium, Leaf and Floral Meristem (FM), as well as their involvement in multiple signaling pathways. We also highlight the evolutionary conservation of the CLE gene family and provide a comprehensive summary of its distribution across various plant developmental tissues. This paper aims to provide insights into novel regulatory networks of CLE in plant meristems, offering guidance for understanding intercellular signaling pathways in forest trees and the development of new plant organs.