Peter Tompa, Monika Fuxreiter, Christopher J. Oldfield, Istvan Simon, A. Keith Dunker and Vladimir N. Uversky
Article first published online: 3 MAR 2009 | DOI: 10.1002/bies.200990014
Cover Photograph: Structure of the actin-regulatory protein thymosin-beta4 (gold) in complex with G-actin (grey). The amino acid sequence corresponding to thymosin beta4 also appears as part of other proteins, when it is termed the WH2 domain. The domain, as also suggested by its extended conformation in the complex, is intrinsically disordered in isolation. Such examples call upon the extension of the domain concept of proteins, as discussed in the article by Tompa et al. (on pages 328-335).