A peptide-mediated, multilateral molecular dialogue for the coordination of pollen wall formation.

The surface of pollen grains is reinforced by pollen wall components produced noncell autonomously by tapetum cells that surround developing pollen within the male floral organ, the anther. Here, we show that tapetum activity is regulated by the GASSHO (GSO) receptor-like kinase pathway, controlled by two sulfated peptides, CASPARIAN STRIP INTEGRITY FACTOR 3 (CIF3) and CIF4, the precursors of which are expressed in the tapetum itself. Coordination of tapetum activity with pollen grain development depends on the action of subtilases, including AtSBT5.4, which are produced stage specifically by developing pollen grains. Tapetum-derived CIF precursors are processed by subtilases, triggering GSO-dependent tapetum activation. We show that the GSO receptors act from the middle layer, a tissue surrounding the tapetum and developing pollen. Three concentrically organized cell types, therefore, cooperate to coordinate pollen wall deposition through a multilateral molecular dialogue.

Citation

Jekaterina Truskina, Stefanie Brück, Annick Stintzi, Sophy Boeuf, Nicolas M Doll, Satoshi Fujita, Niko Geldner, Andreas Schaller, Gwyneth C Ingram. A peptide-mediated, multilateral molecular dialogue for the coordination of pollen wall formation. Proceedings of the National Academy of Sciences of the United States of America. 2022 May 24;119(22):e2201446119

Mesh Tags

Substances

PMID: 35609199

search → result