High impact information on LOC408047

• The source of actin did not influence its polymerization from the thymosin beta 4 complex; rabbit skeletal muscle actin and porcine brain actin were polymerized with equal efficiency from their complexes with thymosin beta 4 by both phalloidin and myosin subfragment 1 [1].
• Polymerization of skeletal muscle actin from the complex with thymosin beta 4 by phalloidin is accompanied by the hydrolysis of the actin-bound ATP to ADP [1].
• The pattern of thymosin beta4 expression in blood vessels indicates a function mainly in development of the blood circulatory system which closely parallels findings in vitro [2].
• Later, thymosin beta4 transcripts are found in the head mesenchyme, somites, dorsal root ganglia, neural tube, brain, blood vessels and feather buds [2].
• At early stages thymosin beta4 is expressed in the mesoderm and endoderm and in Hensen's node [2].

Biological context of LOC408047

• We cloned the chick homologue of Homo sapiens thymosin beta4, encoding a G-actin sequestering factor which plays an important role in angiogenesis, cell motility and tumorigenesis [2].
• Molt induced by infusion of a gonadotropin-releasing hormone agonist (GnRH-A, ([D-leu6,Pro9]-GnRH N-ethylamide]) or feed withdrawal (FW) has been used as a model to study interactions between ovarian activity and thymosin beta 4 during molting in domestic hens [3].
• The actin binding site on thymosin beta4 promotes angiogenesis [4].
• Thymosin beta4 is a ubiquitous 43 amino acid, 5 kDa polypeptide that is an important mediator of cell proliferation, migration, and differentiation [4].

Anatomical context of LOC408047

• These observations indicate that under the growth conditions studied, Tbeta4 is the major actin-sequestering protein in fibroblasts [5].
• Thymosin beta4 is angiogenic and can promote endothelial cell migration and adhesion, tubule formation, aortic ring sprouting, and angiogenesis [4].
• Migration assays with human umbilical vein endothelial cells and vessel sprouting assays using chick aortic arches show that thymosin beta4 and the actin-binding motif of the peptide display near-identical activity at ~50 nM, whereas peptides lacking any portion of the actin motif were inactive [4].

Associations of LOC408047 with chemical compounds

• It is concluded that plasma concentrations of thymosin beta 4 are elevated during molting in domestic hens, but the elevation is not attributable to depressed P4 concentrations [3].
• Fibroblast extracts are analyzed by non-denaturing polyacrylamide gel electrophoresis and immunoblotting where most of the G-actin is detected as a complex with Tbeta4 [5].

Analytical, diagnostic and therapeutic context of LOC408047

• Expression of thymosin beta 4, which is known to be extremely important for G-actin-sequestering in a variety of non-muscle cells, was detected at a considerable level in young embryonic but not in adult skeletal muscles according to Northern and Western blotting [6].
• When fibroblast extracts are fractionated by gel filtration and the fractions are analyzed by PAGE and HPLC, most of the G-actin elutes in a peak that also contains Tbeta4 at an overall molar ratio of 1.9:1 relative to actin [5].
• Furthermore, preliminary radioimmunoassays revealed a sharp increase in the values of circulating thymic hormones, mainly thymosin beta 4 in 17-day-old embryos [7].

References