c-Myc induces chromosomal rearrangements through telomere and chromosome remodeling in the interphase nucleus

Proc Natl Acad Sci U S A. 2005 Jul 5;102(27):9613-8. doi: 10.1073/pnas.0407512102. Epub 2005 Jun 27.

Abstract

In previous work, we showed that telomeres of normal cells are organized within the 3D space of the interphase nucleus in a nonoverlapping and cell cycle-dependent manner. This order is distorted in tumor cell nuclei where telomeres are found in close association forming aggregates of various numbers and sizes. Here we show that c-Myc overexpression induces telomeric aggregations in the interphase nucleus. Directly proportional to the duration of c-Myc deregulation, we observe three or five cycles of telomeric aggregate formation in interphase nuclei. These cycles reflect the onset and propagation of breakage-bridge-fusion cycles that are initiated by end-to-end telomeric fusions of chromosomes. Subsequent to initial chromosomal breakages, new fusions follow and the breakage-bridge-fusion cycles continue. During this time, nonreciprocal translocations are generated. c-Myc-dependent remodeling of the organization of telomeres thus precedes the onset of genomic instability and subsequently leads to chromosomal rearrangements. Our findings reveal that c-Myc possesses the ability to structurally modify chromosomes through telomeric fusions, thereby reorganizing the genetic information.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / physiology
  • Cell Line, Tumor
  • Cell Nucleus / physiology
  • Chromosomal Instability / genetics
  • Chromosomal Instability / physiology*
  • Chromosome Painting
  • Chromosomes, Mammalian / genetics
  • Chromosomes, Mammalian / physiology*
  • Gene Expression Regulation, Neoplastic*
  • Gene Rearrangement / genetics*
  • Image Processing, Computer-Assisted
  • Immunohistochemistry
  • In Situ Hybridization, Fluorescence
  • Interphase / genetics
  • Interphase / physiology*
  • Karyotyping
  • Mice
  • Proto-Oncogene Proteins c-myc / metabolism*
  • Telomere / genetics*

Substances

  • Myc protein, mouse
  • Proto-Oncogene Proteins c-myc