Wiedłocha A
Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, Oslo.
Arch Immunol Ther Exp (Warsz). 1999;47(5):299-305.
Angiogenin is a potent inducer of new blood vessel formation. It binds to high-affinity endothelial cell-surface receptors and, with lower affinity, to extracellular matrix. Angiogenin is the only angiogenic factor known to exhibit ribonucleolytic activity. It belongs to the pancreatic RNase superfamily of proteins. Angiogenin is the only member of the superfamily able to stimulate angiogenesis. Although the catalytic activity of the protein is rather weak, it is critical for its angiogenic properties. Angiogenin is specifically endocytosed by endothelial cells and transported to the nucleus, where it accumulates in the nucleolus. Also, the nuclear location of the angiogenic factor appears to be necessary for its angiogenic activity. The mechanism of action of the protein seems to be unusual, since it does not fit into the current paradigm of how exogenous regulatory polypeptides, including other angiogenic factors, work. Here, the role of transport of angiogenin from the cell-surface into the nucleolus and of its intracellular/nuclear mode of action in stimulation of angiogenesis is discussed.
血管生成素是新血管形成的强效诱导剂。它与高亲和力的内皮细胞表面受体结合，并以较低亲和力与细胞外基质结合。血管生成素是已知唯一具有核糖核酸酶活性的血管生成因子。它属于蛋白质的胰腺核糖核酸酶超家族。血管生成素是该超家族中唯一能够刺激血管生成的成员。尽管该蛋白质的催化活性相当弱，但对其血管生成特性至关重要。血管生成素被内皮细胞特异性内吞并转运到细胞核中，在核仁中积累。此外，血管生成因子在细胞核中的定位似乎对其血管生成活性是必需的。该蛋白质的作用机制似乎不同寻常，因为它不符合包括其他血管生成因子在内的外源性调节多肽目前的作用模式。在此，讨论了血管生成素从细胞表面转运到核仁的作用及其在刺激血管生成中的细胞内/核作用模式。
