Adenomatous polyposis coli and EB1 localize in close proximity of the mother centriole and EB1 is a functional component of centrosomes

J Cell Sci. 2004 Mar 1;117(Pt 7):1117-28. doi: 10.1242/jcs.00939. Epub 2004 Feb 17.

Abstract

Adenomatous polyposis coli (APC) and End-binding protein 1 (EB1) localize to centrosomes independently of cytoplasmic microtubules (MTs) and purify with centrosomes from mammalian cell lines. Localization of EB1 to centrosomes is independent of its MT binding domain and is mediated by its C-terminus. Both APC and EB1 preferentially localize to the mother centriole and EB1 forms a cap at the end of the mother centriole that contains the subdistal appendages as defined by epsilon-tubulin localization. Like endogenous APC and EB1, fluorescent protein fusions of APC and EB1 localize preferentially to the mother centriole. Depletion of EB1 by RNA interference reduces MT minus-end anchoring at centrosomes and delays MT regrowth from centrosomes. In summary, our data indicate that APC and EB1 are functional components of mammalian centrosomes and that EB1 is important for anchoring cytoplasmic MT minus ends to the subdistal appendages of the mother centriole.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenomatous Polyposis Coli Protein / genetics
  • Adenomatous Polyposis Coli Protein / metabolism*
  • Animals
  • COS Cells
  • Cell Line
  • Centrioles / metabolism*
  • Centrosome / metabolism*
  • Dogs
  • Green Fluorescent Proteins
  • HeLa Cells
  • Humans
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Microscopy, Fluorescence
  • Microtubule-Associated Proteins / genetics
  • Microtubule-Associated Proteins / metabolism*
  • Microtubules / drug effects
  • Microtubules / metabolism
  • Nocodazole / pharmacology
  • RNA Interference
  • RNA, Small Interfering / genetics
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism

Substances

  • Adenomatous Polyposis Coli Protein
  • EB1 microtubule binding proteins
  • Luminescent Proteins
  • Microtubule-Associated Proteins
  • RNA, Small Interfering
  • Recombinant Fusion Proteins
  • Green Fluorescent Proteins
  • Nocodazole