CLAVATA modulates auxin homeostasis and transport to regulate stem cell identity and plant shape in a moss

0563454 - ÚEB 2023 RIV GB eng J - Journal Article
Nemec-Venza, Z. - Madden, C. - Stewart, A. - Liu, W. - Novák, Ondřej - Pěnčík, Aleš - Cuming, A. C. - Kamisugi, Y. - Harrison, C.J.
CLAVATA modulates auxin homeostasis and transport to regulate stem cell identity and plant shape in a moss.
New Phytologist. Roč. 234, č. 1 (2022), s. 149-163. ISSN 0028-646X. E-ISSN 1469-8137
R&D Projects: GA MŠMT(CZ) EF16_019/0000827
Institutional support: RVO:61389030
Keywords : clavata * clv-wus * evo-devo * moss filament identity * physcomitrella * plant stem cell
OECD category: Biochemistry and molecular biology
Impact factor: 9.4, year: 2022
Method of publishing: Open access
https://doi.org/10.1111/nph.17969

The CLAVATA pathway is a key regulator of stem cell function in the multicellular shoot tips of Arabidopsis, where it acts via the WUSCHEL transcription factor to modulate hormone homeostasis. Broad-scale evolutionary comparisons have shown that CLAVATA is a conserved regulator of land plant stem cell function, but CLAVATA acts independently of WUSCHEL-like (WOX) proteins in bryophytes. The relationship between CLAVATA, hormone homeostasis and the evolution of land plant stem cell functions is unknown. Here we show that in the moss, Physcomitrella (Physcomitrium patens), CLAVATA affects stem cell activity by modulating hormone homeostasis. CLAVATA pathway genes are expressed in the tip cells of filamentous tissues, regulating cell identity, filament branching, plant spread and auxin synthesis. The receptor-like kinase PpRPK2 plays the major role, and Pprpk2 mutants have abnormal responses to cytokinin, auxin and auxin transport inhibition, and show reduced expression of PIN auxin transporters. We propose a model whereby PpRPK2 modulates auxin gradients in filaments to determine stem cell identity and overall plant form. Our data indicate that CLAVATA-mediated auxin homeostasis is a fundamental property of plant stem cell function, probably exhibited by the last shared common ancestor of land plants.
Permanent Link: https://hdl.handle.net/11104/0335411