Versatile fluorescent probes for actin filaments based on the actin-binding domain of utrophin

Cell Motil Cytoskeleton. 2007 Nov;64(11):822-32. doi: 10.1002/cm.20226.


Actin filaments (F-actin) are protein polymers that undergo rapid assembly and disassembly and control an enormous variety of cellular processes ranging from force production to regulation of signal transduction. Consequently, imaging of F-actin has become an increasingly important goal for biologists seeking to understand how cells and tissues function. However, most of the available means for imaging F-actin in living cells suffer from one or more biological or experimental shortcomings. Here we describe fluorescent F-actin probes based on the calponin homology domain of utrophin (Utr-CH), which binds F-actin without stabilizing it in vitro. We show that these probes faithfully report the distribution of F-actin in living and fixed cells, distinguish between stable and dynamic F-actin, and have no obvious effects on processes that depend critically on the balance of actin assembly and disassembly.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Actin Cytoskeleton / metabolism*
  • Animals
  • Female
  • Fluorescent Antibody Technique / methods
  • Fluorescent Dyes / metabolism*
  • Humans
  • Microfilament Proteins / metabolism*
  • Photobleaching
  • Protein Structure, Tertiary
  • Utrophin / metabolism*
  • Xenopus


  • Fluorescent Dyes
  • Microfilament Proteins
  • Utrophin