Regulation of the Pollen-Specific Actin-Depolymerizing Factor LlADF1
AUTOR(ES)
Allwood, Ellen G.
FONTE
American Society of Plant Biologists
RESUMO
Pollen tube growth is dependent on a dynamic actin cytoskeleton, suggesting that actin-regulating proteins are involved. We have examined the regulation of the lily pollen-specific actin-depolymerizing factor (ADF) LlADF1. Its actin binding and depolymerizing activity is pH sensitive, inhibited by certain phosphoinositides, but not controlled by phosphorylation. Compared with its F-actin binding properties, its low activity in depolymerization assays has been used to explain why pollen ADF decorates F-actin in pollen grains. This low activity is incompatible with a role in increasing actin dynamics necessary to promote pollen tube growth. We have identified a plant homolog of actin-interacting protein, AIP1, which enhances the depolymerization of F-actin in the presence of LlADF1 by ∼60%. Both pollen ADF and pollen AIP1 bind F-actin in pollen grains but are mainly cytoplasmic in pollen tubes. Our results suggest that together these proteins remodel actin filaments as pollen grains enter and exit dormancy.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=152736Documentos Relacionados
- The Regulation of Actin Organization by Actin-Depolymerizing Factor in Elongating Pollen TubesW⃞
- Regulation of a Wheat Actin-Depolymerizing Factor during Cold Acclimation1
- Actin-Depolymerizing Factor Mediates Rac/Rop GTPase–Regulated Pollen Tube Growth
- A Zea mays pollen cDNA encoding a putative actin-depolymerizing factor.
- The Three Mouse Actin-depolymerizing Factor/Cofilins Evolved to Fulfill Cell-Type–specific Requirements for Actin Dynamics
