Self-incompatibility in Papaver targets soluble inorganic pyrophosphatases in pollen

De Graaf, Barend H. J. ORCID: https://orcid.org/0000-0003-0542-5510, Rudd, Jason J., Wheeler, M. J., Perry, R. M., Bell, E. M., Osman, K., Franklin, F. C. H. and Franklin-Tong, V. E. 2006. Self-incompatibility in Papaver targets soluble inorganic pyrophosphatases in pollen. Nature 444 , pp. 490-493. 10.1038/nature05311

Full text not available from this repository.

Abstract

In higher plants, sexual reproduction involves interactions between pollen and pistil. A key mechanism to prevent inbreeding is self-incompatibility through rejection of incompatible ('self') pollen1. In Papaver rhoeas, S proteins encoded by the stigma interact with incompatible pollen, triggering a Ca2+-dependent signalling network2, 3, 4, 5 resulting in pollen tube inhibition and programmed cell death6. The cytosolic phosphoprotein p26.1, which has been identified in incompatible pollen, shows rapid, self-incompatibility-induced Ca2+-dependent hyperphosphorylation in vivo3. Here we show that p26.1 comprises two proteins, Pr-p26.1a and Pr-p26.1b, which are soluble inorganic pyrophosphatases (sPPases). These proteins have classic Mg2+-dependent sPPase activity, which is inhibited by Ca2+, and unexpectedly can be phosphorylated in vitro. We show that phosphorylation inhibits sPPase activity, establishing a previously unknown mechanism for regulating eukaryotic sPPases. Reduced sPPase activity is predicted to result in the inhibition of many biosynthetic pathways, suggesting that there may be additional mechanisms of self-incompatibility-mediated pollen tube inhibition. We provide evidence that sPPases are required for growth and that self-incompatibility results in an increase in inorganic pyrophosphate, implying a functional role for Pr-p26.1.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Biosciences
Publisher:	Nature Publishing Group
ISSN:	0028-0836
Last Modified:	25 Oct 2022 10:06
URI:	https://orca.cardiff.ac.uk/id/eprint/61165

Citation Data

Cited 71 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item