Thymosin Beta-4 (TB-500) 10mg

Overview

Thymosin β4 (Tβ4) is a 43-amino-acid peptide and the most abundant member of the β-thymosin family, present at high concentration in platelets, leukocytes and most mammalian cell types. Its primary intracellular role is sequestration of monomeric G-actin, which makes it a central regulator of the actin cytoskeleton. The designation “TB-500” is widely used in research-supply nomenclature for synthetic Tβ4 and its active fragment; the material supplied is described on the lot COA.

Acu Aminos supplies TB-500 as a 10 mg lyophilized powder for laboratory cell-biology research.

Chemistry & specifications

Tβ4 is a highly conserved, N-terminally acetylated, intrinsically disordered peptide. Its central actin-binding motif, LKKTETQ (residues 17–23), is required for G-actin sequestration and is the region most frequently synthesized as a stand-alone fragment in structure-function work. The full-length peptide adopts helical structure at the N- and C-termini upon binding actin.

Cellular structure & mechanism of action

By binding G-actin in a 1:1 complex, Tβ4 maintains the pool of unpolymerized actin that cells draw on for rapid cytoskeletal remodeling. In cell-culture and animal models, Tβ4 has been reported to promote endothelial and keratinocyte migration, stimulate angiogenesis, down-regulate inflammatory cytokines and reduce apoptosis. A well-known mechanistic study demonstrated that Tβ4 forms a complex with PINCH and integrin-linked kinase (ILK), activating Akt survival signaling in cardiac cells. Extracellular Tβ4 also serves as the precursor of the tetrapeptide Ac-SDKP, which has its own biological activity in the literature.

Research applications

• Actin-polymerization and G-actin sequestration assays
• Endothelial, keratinocyte and fibroblast migration (scratch) assays
• Angiogenesis and tube-formation models
• ILK/Akt signaling and cardiomyocyte survival research
• Corneal epithelial and dermal wound models

Selected references

1. Safer D, Elzinga M, Nachmias VT. Thymosin β4 and Fx, an actin-sequestering peptide, are indistinguishable. J Biol Chem. 1991;266:4029–4032.
2. Bock-Marquette I, Saxena A, White MD, DiMaio JM, Srivastava D. Thymosin β4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair. Nature. 2004;432:466–472.
3. Goldstein AL, Hannappel E, Kleinman HK. Thymosin β4: actin-sequestering protein moonlights to repair injured tissues. Trends Mol Med. 2005;11(9):421–429.

References are provided to help researchers locate primary literature. Acu Aminos makes no claims about the safety or efficacy of any compound in humans or animals.