Amphiphysin 1 is important for actin polymerization during phagocytosis

Hiroshi Yamada, Emiko Ohashi, Tadashi Abe, Norihiro Kusumi, Shun Ai Li, Yumi Yoshida, Masami Watanabe, Kazuhito Tomizawa, Yuji Kashiwakura, Hiromi Kumon, Hideki Matsui, Kohji Takei

Research output: Contribution to journalArticlepeer-review

33 Citations (Scopus)


Amphiphysin 1 is involved in clathrin-mediated endocytosis. In this study, we demonstrate that amphiphysin 1 is essential for cellular phagocytosis and that it is critical for actin polymerization. Phagocytosis in Sertoli cells was induced by stimulating phosphatidylserine receptors. This stimulation led to the formation of actin-rich structures, including ruffles, phagocytic cups, and phagosomes, all of which showed an accumulation of amphiphysin 1. Knocking out amphiphysin 1 by RNA interference in the cells resulted in the reduction of ruffle formation, actin polymerization, and phagocytosis. Phagocytosis was also drastically decreased in amph 1 (-/-) Sertoli cells. In addition, phosphatidylinositol-4,5-bisphosphate-induced actin polymerization was decreased in the knockout testis cytosol. The addition of recombinant amphiphysin 1 to the cytosol restored the polymerization process. Ruffle formation in small interfering RNA-treated cells was recovered by the expression of constitutively active Rac1, suggesting that amphiphysin 1 functions upstream of the protein. These findings support that amphiphysin 1 is important in the regulation of actin dynamics and that it is required for phagocytosis.

Original languageEnglish
Pages (from-to)4669-4680
Number of pages12
JournalMolecular Biology of the Cell
Issue number11
Publication statusPublished - Nov 2007

ASJC Scopus subject areas

  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'Amphiphysin 1 is important for actin polymerization during phagocytosis'. Together they form a unique fingerprint.

Cite this