Location: Plant Gene Expression CenterTitle: Interactive CLV3, CLE16 and CLE17 signaling mediates stem cell homeostasis in the Arabidopsis shoot apical meristem
|DAO, THAI - University Of California
|WEKSLER, NAAMA - University Of California
|LIU, HANNAH - University Of California
|LEIBOFF, SAMUEL - Oregon State University
Submitted to: Development
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/30/2022
Publication Date: 9/29/2022
Citation: Dao, T.Q., Weksler, N., Liu, H.M., Leiboff, S., Fletcher, J.C. 2022. Interactive CLV3, CLE16 and CLE17 signaling mediates stem cell homeostasis in the Arabidopsis shoot apical meristem. Development. 149(19). Article dev200787. https://doi.org/10.1242/dev.200787.
Interpretive Summary: Sustaining agricultural productivity is an important national food security issue in order to meet the needs of our growing population. Research has shown that agricultural yield traits can be improved by understanding how stem cells are maintained within the growing tips of plants, called meristems, which produce the leaves, fruits and seeds that humans cultivate and eat. Our previous studies showed that a gene called CLAVATA3 (CLV3) plays a key role in controlling plant stem cell activity by signaling between neighboring meristem cells. Here we demonstrate that CLV3 acts along with the closely related CLE16 and CLE17 genes to regulate the number of stem cells produced by the shoot and flower meristems. We show that a set of genes called the BAM receptors recognize the CLE16 and CLE17 signals and also that cells expressing a target gene called WUSCHEL respond to CLE16/17 signaling via these BAM receptors. Our study expands the set of genes that can be targeted in crop species to increase yield traits such as fruit number, fruit size and seed number.
Technical Abstract: The ability of plants to grow and form organs throughout their lifetime is dependent on their sustained stem cell activity. These stem cell populations are maintained by intricate networks of intercellular signaling pathways. In Arabidopsis thaliana, the small secreted peptide CLAVATA3 (CLV3) controls shoot apical meristem (SAM) maintenance by activating a signal transduction pathway that modulates the expression of the homeodomain transcription factor WUSCHEL (WUS). Here, we demonstrate that two CLV3-related peptides, CLE16 and CLE17, restrict stem cell accumulation in the absence of CLV3. CLE16 and CLE17 contribute independently to SAM maintenance and organ production in clv3 plants at all stages of development. We demonstrate that CLE16 and CLE17 signal through a subset of CLV3 receptors, the BARELY ANY MERISTEM (BAM) receptor kinases, and act upstream of WUS but in parallel to STM. Finally, we show that CLV3, CLE16 and CLE17 have a WUS-independent role in regulating axillary meristem initiation and outgrowth. Our study reveals that CLE16 and CLE17 function in a mechanism that partially compensates for CLV3 to maintain stem cell homeostasis and expands the potential targets for enhancing yield traits in crop species.