HSPB1 facilitates the formation of non-centrosomal microtubules

PLoS One. 2013 Jun 24;8(6):e66541. doi: 10.1371/journal.pone.0066541. Print 2013.

Abstract

The remodeling capacity of microtubules (MT) is essential for their proper function. In mammals, MTs are predominantly formed at the centrosome, but can also originate from non-centrosomal sites, a process that is still poorly understood. We here show that the small heat shock protein HSPB1 plays a role in the control of non-centrosomal MT formation. The HSPB1 expression level regulates the balance between centrosomal and non-centrosomal MTs. The HSPB1 protein can be detected specifically at sites of de novo forming non-centrosomal MTs, while it is absent from the centrosomes. In addition, we show that HSPB1 binds preferentially to the lattice of newly formed MTs in vitro, suggesting that its function occurs by stabilizing MT seeds. Our findings open new avenues for the understanding of the role of HSPB1 in the development, maintenance and protection of cells with specialized non-centrosomal MT arrays.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Centrosome*
  • Cricetulus
  • HSP27 Heat-Shock Proteins / metabolism
  • HSP27 Heat-Shock Proteins / physiology*
  • HeLa Cells
  • Heat-Shock Proteins
  • Humans
  • Microscopy, Immunoelectron
  • Microtubules / metabolism*
  • Molecular Chaperones
  • Protein Binding

Substances

  • HSP27 Heat-Shock Proteins
  • HSPB1 protein, human
  • Heat-Shock Proteins
  • Molecular Chaperones

Grants and funding

This work was supported in part by the special research fund and the Methusalem program of the University of Antwerp, the Fund for Scientific Research (FWO-Flanders), the Medical Foundation Queen Elisabeth (GSKE), the “Association Belge contre les Maladies Neuromusculaires” (ABMM), the American Muscular Dystrophy Association (MDA). We thank the Hercules foundation providing funding for the transmission electron and spinning disk microscopes. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.