β-thymosin 4 (Tβ4) is a prototypical actin-monomer sequestering protein that plays an important role in mammalian cells and tissues. In vertebrates, Tβ4 is involved in various physiological and pathophysiological processes, such as angiogenesis, hair follicle and hair regeneration, nervous system development, inflammatory response, wound healing, tumour metastasis, and liver and heart protection. Additionally, thymosin domain-containing protein was discovered in invertebrates and was recently shown to be more homologous to Tβ4. However, the structural and functional properties are more complex and diverse than those of Tβ4. In this review article, we will discuss in detail the structural and functional aspects of β-thymosin in invertebrates.
Keywords: β-thymosin, Tβ4, multimeric β-thymosin, structure, function, munomeric, β-thymosin.