Human NUF2 interacts with centromere-associated protein E and is essential for a stable spindle microtubule-kinetochore attachment

J Biol Chem. 2007 Jul 20;282(29):21415-24. doi: 10.1074/jbc.M609026200. Epub 2007 May 29.

Abstract

Chromosome segregation in mitosis is orchestrated by dynamic interaction between spindle microtubules and the kinetochore, a multiprotein complex assembled onto centromeric DNA of the chromosome. Here, we show that Homo sapiens (Hs) NUF2 is required for stable kinetochore localization of centromere-associated protein E (CENP-E) in HeLa cells. HsNUF2 specifies the kinetochore association of CENP-E by interacting with its C-terminal domain. The region of HsNUF2 binding to CENP-E was mapped to its C-terminal domain by glutathione S-transferase pulldown and yeast two-hybrid assays. Suppression of synthesis of HsNUF2 by small interfering RNA abrogated the localization of CENP-E to the kinetochore, demonstrating the requirement of HsNUF2 for CENP-E kinetochore localization. In addition, depletion of HsNUF2 caused aberrant chromosome segregation. These HsNUF2-suppressed cells displayed reduced tension at kinetochores of bi-orientated chromosomes. Double knockdown of CENP-E and HsNUF2 further abolished the tension at the kinetochores. Our results indicate that HsNUF2 and CENP-E are required for organization of stable microtubule-kinetochore attachment that is essential for faithful chromosome segregation in mitosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Cycle Proteins / chemistry*
  • Cell Line
  • Centromere / metabolism*
  • Chromosomal Proteins, Non-Histone / chemistry*
  • Chromosomes / ultrastructure
  • HeLa Cells
  • Humans
  • Kinetochores / metabolism*
  • Microtubules / metabolism*
  • Mitosis
  • Models, Biological
  • Models, Genetic
  • Protein Structure, Tertiary
  • RNA, Small Interfering / metabolism
  • Two-Hybrid System Techniques

Substances

  • Cell Cycle Proteins
  • Chromosomal Proteins, Non-Histone
  • NUF2 protein, human
  • RNA, Small Interfering
  • centromere protein E