Mammalian actin binding protein 1 is essential for endocytosis but not lamellipodia formation: Functional analysis by RNA interference

Setsuko Mise-Omata, Benjamin Montagne, Marcel Deckert, Jürgen Wienands, Oreste Acuto

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

Mammalian actin binding protein 1 (mAbp1, also called SH3P7/Hip55) is structurally and functionally related to yeast Abp1 and to cortactin, both of which have been implicated in endocytotic processes. mAbp1 associates through its SH3 domain with dynamin, a large GTPase essential for vesicle fission. To clarify the function of mAbp1, we specifically knocked down its expression in human embryonic kidney 293T cells, using RNA interference (RNAi). Co-transfection of a short interfering RNA (siRNA) together with a plasmid coding for a surface marker, followed by purification of transfected cells, enabled us to obtain a cell population having up to 90% inhibition of mAbp1 expression. In mAbp1-knocked down cells, transferrin (Tf) receptor endocytosis was significantly inhibited and intracellular distribution of the early endosomal compartment was modified. In contrast, in these cells actin and microtubule filaments appeared normal, and formation of lamellipodia induced by active Rac was not inhibited. This study provides definitive evidence that mAbp1 is indispensable for receptor-mediated endocytosis.

Original languageEnglish
Pages (from-to)704-710
Number of pages7
JournalBiochemical and Biophysical Research Communications
Volume301
Issue number3
DOIs
Publication statusPublished - 2003 Feb 14
Externally publishedYes

Keywords

  • Dynamin
  • Lamellipodia
  • mAbp1
  • Receptor-mediated endocytosis
  • SH3P7

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Mammalian actin binding protein 1 is essential for endocytosis but not lamellipodia formation: Functional analysis by RNA interference'. Together they form a unique fingerprint.

  • Cite this