Villin controls the formation and enlargement of punctate actin foci in pollen tubes.
J Cell Sci
; 133(6)2020 03 18.
Article
en En
| MEDLINE
| ID: mdl-32051284
ABSTRACT
Self-incompatibility (SI) in the poppy Papaver rhoeas triggers dramatic alterations in actin within pollen tubes. However, how these actin alterations are mechanistically achieved remains largely unexplored. Here, we used treatment with the Ca2+ ionophore A23187 to mimic the SI-induced elevation in cytosolic Ca2+ and trigger formation of the distinctive F-actin foci. Live-cell imaging revealed that this remodeling involves F-actin fragmentation and depolymerization, accompanied by the rapid formation of punctate actin foci and subsequent increase in their size. We established that actin foci are generated and enlarged from crosslinking of fragmented actin filament structures. Moreover, we show that villins associate with actin structures and are involved in this actin reorganization process. Notably, we demonstrate that Arabidopsis VILLIN5 promotes actin depolymerization and formation of actin foci by fragmenting actin filaments, and controlling the enlargement of actin foci via bundling of actin filaments. Our study thus uncovers important novel insights about the molecular players and mechanisms involved in forming the distinctive actin foci in pollen tubes.
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Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Actinas
/
Tubo Polínico
/
Proteínas de Microfilamentos
Idioma:
En
Año:
2020
Tipo del documento:
Article