Micromechanical studies of mitotic chromosomes

Chromosome Res. 2008;16(3):469-97. doi: 10.1007/s10577-008-1233-7.

Abstract

Mitotic chromosomes respond elastically to forces in the nanonewton range, a property important to transduction of stresses used as mechanical regulatory signals during cell division. In addition to being important biologically, chromosome elasticity can be used as a tool for investigating the folding of chromatin. This paper reviews experiments studying stretching and bending stiffness of mitotic chromosomes, plus experiments where changes in chromosome elasticity resulting from chemical and enzyme treatments were used to analyse connectivity of chromatin inside chromosomes. Experiments with nucleases indicate that non-DNA elements constraining mitotic chromatin must be isolated from one another, leading to the conclusion that mitotic chromosomes have a chromatin 'network' or 'gel' organization, with stretches of chromatin strung between 'crosslinking' points. The as-yet unresolved questions of the identities of the putative chromatin crosslinkers and their organization inside mitotic chromosomes are discussed.

Publication types

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

MeSH terms

  • Animals
  • Biomechanical Phenomena
  • Chromatin / physiology
  • Chromosomal Proteins, Non-Histone / physiology
  • Chromosomes / physiology*
  • DNA Topoisomerases, Type II / physiology
  • Deoxyribonucleases
  • Elasticity
  • Humans
  • Micromanipulation
  • Microscopy, Phase-Contrast
  • Mitosis
  • Models, Biological
  • Peptide Hydrolases
  • Salts

Substances

  • Chromatin
  • Chromosomal Proteins, Non-Histone
  • Salts
  • Deoxyribonucleases
  • Peptide Hydrolases
  • DNA Topoisomerases, Type II