Villin controls the formation and enlargement of punctate actin foci in pollen tubes

Research output: Contribution to journalArticlepeer-review

Authors

  • Wanying Zhao
  • Xiaolu Qu
  • Yuhui Zhuang
  • Ludi Wang
  • Yongbiao Xue
  • Shanjin Huang

Colleges, School and Institutes

External organisations

  • Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
  • Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
  • Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China
  • State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China

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.

Details

Original languageEnglish
Article numberjcs237404
JournalJournal of Cell Science
Volume133
Issue number6
Early online date12 Feb 2020
Publication statusPublished - 18 Mar 2020