The Pollen Coat Proteome: At the Cutting Edge of Plant Reproduction

The tapetum is a single layer of secretory cells which encloses the anther locule and sustains pollen development and maturation. Upon apoptosis, the remnants of the tapetal cells, consisting mostly of lipids and proteins, fill the pits of the sculpted exine to form the bulk of the pollen coat. This extracellular matrix forms an impermeable barrier that protects the male gametophyte from water loss and UV light. It also aids pollen adhesion and hydration and retains small signaling compounds involved in pollen–stigma communication. In this study, we have updated the list of the pollen coat’s protein components and also discussed their functions in the context of sexual reproductionThis study was supported by ERDF-confinanced grants PIE-200840I186 and AGL2008-00517/AGR (MICINN), AGL2013-43042-P and BFU2011-22779 (MINECO), and P10-CVI-5767 (Junta de Andalucía). It was also funded by the CNRS, the “Agence National de la Recherche” (ANR), the “Region Alsace” and the French National Proteomic Infrastructure (grant ANR-10-INBS-08; ProFI; the “Infrastructures Nationales en Biologie et Santé” project). We also wish to thank Krysztof Zienkiewicz for kindly providing us with the image in Figure 1b. English proofreading was done by Michael O’Shea.We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)