The full 43-residue peptide behind the widely discussed TB-500 fragment.
Also known as: TB4 · Tβ4
Part of the Repair & recovery peptides cluster
Overview
Thymosin beta-4 is a naturally occurring 43-amino-acid peptide and the principal actin-sequestering molecule in many cell types. The research compound TB-500 is derived from an active region of this larger peptide. Thymosin beta-4 is investigational and not authorized by Health Canada; this page is educational only.
Source & context
Biological / chemical source: Naturally occurring 43-residue intracellular peptide
Primary research or clinical context: Investigational research peptide; not authorized by Health Canada
Actin regulation
Thymosin beta-4 (SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES) binds monomeric G-actin and holds it in reserve, buffering the balance between free actin and filaments. This role in cytoskeletal dynamics underlies its study in cell motility, and it is why the peptide is examined in tissue-repair research.
Relationship to TB-500 and status
TB-500 corresponds to an active fragment associated with thymosin beta-4 rather than the whole peptide, which is why the two names are often confused. Thymosin beta-4 itself is an investigational research compound, not an approved drug in Canada. This summary is educational and makes no therapeutic claims.
Sequence
One-letter sequence commonly cited for Thymosin beta-4 (educational; isoforms and modifications may differ):
SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES
Residues plotted ~100° apart around an α-helix — clustering of one color reveals an amphipathic face.
FAQ about Thymosin beta-4
What is Thymosin beta-4?+
Thymosin beta-4 is a naturally occurring 43-amino-acid peptide and the principal actin-sequestering molecule in many cell types. The research compound TB-500 is derived from an active region of this larger peptide. Thymosin beta-4 is investigational and not authorized by Health Canada; this page is educational only.
Is Thymosin beta-4 an approved medicine?+
Thymosin beta-4 is discussed here as a research / educational topic. Investigational research peptide; not authorized by Health Canada. This is not medical advice.
What is the typical length of Thymosin beta-4?+
Thymosin beta-4 is commonly described as approximately 43 amino acids (Actin-sequestering peptide).