Growth-inhibiting effects of the unconventional plant APYRASE 7 of < i > Arabidopsis thaliana < /i > influences the LRX/RALF/FER growth regulatory module

by Shibu Gupta, Amandine Gu érin, Aline Herger, Xiaoyu Hou, Myriam Schaufelberger, Romain Roulard, Anouck Diet, Stefan Roffler, Valérie Lefebvre, Thomas Wicker, Jérôme Pelloux, Christoph Ringli Plant cell growth involves coordination of numerous processes and signaling cascades among the different cellular compartments to concomitantly enlarge the protoplast and the surrounding cell wall. The cell wall integrity-sensing process involves the extracellular LRX (LRR-Extensin) proteins that bind RALF (Rapid ALkalinization Factor) peptide hormones and, in vegetative tissues, interact with the transmembrane receptor kinase FERONIA (FER). This LRX/RALF/FER signaling module influences cell wall composition and regulates cell growth. The numerous proteins involved in or influenced by this module are beginning to be characterized. In a genetic screen, mutations inApyrase 7 (APY7) were identified to suppress growth defects observed inlrx1 andfer mutants.APY7 encodes a Golgi-localized NTP-diphosphohydrolase, but opposed to other apyrases of Arabidopsis, APY7 revealed to be a negative regulator of cell growth. APY7 modulates the growth-inhibiting effect of RALF1, influences the cell wall architecture and -composition, and alters the pH of the extracellular matrix, all of which affect cell growth. Together, this study reveals a function of APY7 in cell wall formation and cell growth that is connected to growth processes influenced by the LRX/RALF/FER signaling module.
Source: PLoS Genetics - Category: Genetics & Stem Cells Authors: Source Type: research