INCENP binds directly to tubulin and requires dynamic microtubules to target to the cleavage furrow

Exp Cell Res. 2001 Jan 15;262(2):122-7. doi: 10.1006/excr.2000.5088.


Inner centromere protein (INCENP) is a chromosomal passenger protein with an essential role in mitosis. At the metaphase/anaphase transition, some INCENP transfers from the centromeres to the central spindle; the remainder then transfers to the equatorial cortex prior to cleavage furrow formation. The molecular associations dictating INCENP behavior during mitosis are currently unknown. Here we show that targeting INCENP to the cleavage plane requires dynamic microtubules, but not F-actin. When microtubules are eliminated, INCENP is dispersed across the entire cell cortex. Yeast two-hybrid and in vitro binding data demonstrate that INCENP binds directly to beta-tubulin via a conserved domain encompassing residues 48-85. Furthermore, INCENP binds to microtubules polymerized from purified tubulin in vitro and appears to bundle microtubules when expressed in the interphase cytoplasm. These data indicate that INCENP is a microtubule-binding protein that targets to the equatorial cortex through interactions requiring microtubules.

MeSH terms

  • Actins / metabolism
  • Amino Acid Motifs / physiology
  • Anaphase / physiology
  • Animals
  • Binding Sites
  • Cell Line
  • Chickens
  • Chromosomal Proteins, Non-Histone / genetics
  • Chromosomal Proteins, Non-Histone / metabolism*
  • Conserved Sequence
  • Fluorescent Antibody Technique, Indirect
  • Humans
  • Metaphase / physiology
  • Microtubules / metabolism*
  • Mitosis / drug effects
  • Mitosis / physiology*
  • Paclitaxel / pharmacology
  • Protein Binding / physiology
  • Protein Structure, Tertiary / genetics
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Tubulin / genetics
  • Tubulin / metabolism*
  • Two-Hybrid System Techniques


  • Actins
  • Chromosomal Proteins, Non-Histone
  • INCENP protein, human
  • Recombinant Fusion Proteins
  • Tubulin
  • Paclitaxel