EXO70A2 is critical for exocyst complex function in pollen development

0539308 - ÚEB 2021 RIV US eng J - Článek v odborném periodiku
Marković, Vedrana - Cvrčková, F. - Potocký, Martin - Kulich, I. - Pejchar, Přemysl - Kollárová, E. - Synek, Lukáš - Žárský, Viktor
EXO70A2 is critical for exocyst complex function in pollen development.
Plant Physiology. Roč. 184, č. 4 (2020), s. 1823-1839. ISSN 0032-0889. E-ISSN 1532-2548
Grant CEP: GA ČR(CZ) GC18-18290J; GA MŠMT(CZ) EF16_019/0000738; GA MŠMT(CZ) LM2015062
Grant ostatní: OPPK(XE) CZ.2.16/3.1.00/21519; OPPK(XE) CZ.2.16/3.1.00/21515
Institucionální podpora: RVO:61389030
Klíčová slova: SUBUNIT EXO70B1 * CELL-WALL * PECTIN METHYLESTERASE
Obor OECD: Cell biology
Impakt faktor: 8.340, rok: 2020
Způsob publikování: Open access
http://doi.org/10.1104/pp.19.01340

Pollen development, pollen grain germination, and pollen tube elongation are crucial biological processes in angiosperm plants that need precise regulation to deliver sperm cells to ovules for fertilization. Highly polarized secretion at a growing pollen tube tip requires the exocyst tethering complex responsible for specific targeting of secretory vesicles to the plasma membrane. Here, we demonstrate that Arabidopsis (Arabidopsis thaliana) EXO70A2 (At5g52340) is the main exocyst EXO70 isoform in the male gametophyte, governing the conventional secretory function of the exocyst, analogous to EXO70A1 (At5g03540) in the sporophyte. Our analysis of a CRISPR-generated exo70a2 mutant revealed that EXO70A2 is essential for efficient pollen maturation, pollen grain germination, and pollen tube growth. GFP:EXO70A2 was localized to the nucleus and cytoplasm in developing pollen grains and later to the apical domain in growing pollen tube tips characterized by intensive exocytosis. Moreover, EXO70A2 could substitute for EXO70A1 function in the sporophyte, but not vice versa, indicating partial functional redundancy of these two closely related isoforms and higher specificity of EXO70A2 for pollen development-related processes. Phylogenetic analysis revealed that the ancient duplication of EXO70A, one of which is always highly expressed in pollen, occurred independently in monocots and dicots. In summary, EXO70A2 is a crucial component of the exocyst complex in Arabidopsis pollen that is required for efficient plant sexual reproduction.
Trvalý link: http://hdl.handle.net/11104/0317007