Andreasen P A, Riccio A, Welinder K G, Douglas R, Sartorio R, Nielsen L S, Oppenheimer C, Blasi F, Danø K
FEBS Lett. 1986 Dec 15;209(2):213-8. doi: 10.1016/0014-5793(86)81113-9.
Both the urokinase-type and tissue-type plasminogen activator can convert their approximately 54 kDa type-1 inhibitor (PAI-1) to an inactive form with a lower apparent molecular mass. We have determined the amino-terminal amino acid sequences of human native and converted PAI-1, and isolated PAI-1 cDNA and determined the nucleotide sequence in regions corresponding to the amino-terminus and the cleavage site. The data show that the conversion of the inhibitor consists of cleavage of an Arg-Met bond 33 residues from the carboxy-terminus, thus localizing the reactive center of the inhibitor to that position. In addition, a heterogeneity was found at the amino-terminus, with a Ser-Ala-Val-His-His form and a two-residue shorter form (Val-His-His-) occurring in approximately equal quantities.
尿激酶型和组织型纤溶酶原激活剂均可将其约54 kDa的1型抑制剂（PAI-1）转化为表观分子量较低的无活性形式。我们已确定了人天然及转化型PAI-1的氨基末端氨基酸序列，分离出PAI-1 cDNA并确定了对应于氨基末端和裂解位点区域的核苷酸序列。数据表明，抑制剂的转化包括从羧基末端起33个残基处的精氨酸-甲硫氨酸键的裂解，从而将抑制剂的反应中心定位到该位置。此外，在氨基末端发现了异质性，丝氨酸-丙氨酸-缬氨酸-组氨酸-组氨酸形式和短两个残基的形式（缬氨酸-组氨酸-组氨酸-）出现的量大致相等。
