PROSITE documentation PDOC00433
Thymosin beta-4 family signature


Thymosin β-4 [1] is a polypeptide of 43 amino acid residues which plays an important role in the organization of the cytoskeleton. It binds to and sequesters actin monomers (G actin) and therefore inhibits actin polymerization.

The sequence of thymosin β-4 is extremely well conserved in mammals and amphibians. A number of peptides closely related to thymosin β-4 are known to exist: thymosin β-9 (and β-8) in bovine and pig, thymosin β-10 in man and rat, thymosin β-11 and β-12 in trout and human Nb thymosin β.

As a signature pattern for this family, we selected a stretch of 12 highly conserved residues located in the central part of the thymosin β proteins. This region, rich in charged residues, lies between two α-helical regions and is involved in the binding of actin.

Last update:

January 2002 / Pattern and text revised.


Technical section

PROSITE method (with tools and information) covered by this documentation:

THYMOSIN_B4, PS00500; Thymosin beta-4 family signature  (PATTERN)


1AuthorsHuff T. Mueller C.S.G. Otto A.M. Netzker R. Hannappel E.
Titlebeta-Thymosins, small acidic peptides with multiple functions.
SourceInt. J. Biochem. Cell Biol. 33:205-220(2001).
PubMed ID11311852

PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see prosite_license.html.


View entry in original PROSITE document format
View entry in raw text format (no links)