Elzanowski A, Barker W C, Hunt L T, Seibel-Ross E
National Biomedical Research Foundation, Georgetown University Medical Center, Washington, DC 20007.
FEBS Lett. 1988 Jan 25;227(2):167-70. doi: 10.1016/0014-5793(88)80890-1.
We have found that chain A of alpha-2-HS-glycoprotein contains two cystatin domains that show closest similarity to those of kininogen. Most likely, the two proteins diverged after the primary duplication of a single cystatin domain as the two cystatin domains of alpha-2-HS-glycoprotein are more similar, especially in disulfide bonding, to the corresponding domains of kininogen than to each other. We also propose that the carboxyl-terminal (non-cystatin) parts of kininogen and alpha-2-HS-glycoprotein contain homologous segments. We suggest that alpha-2-HS-glycoprotein may act as an inhibitor of the cysteine proteinases responsible for bone resorption. We have also found that fetuin is closely related to alpha-2-HS-glycoprotein.
我们发现α-2-HS-糖蛋白的A链含有两个胱抑素结构域，它们与激肽原的胱抑素结构域最为相似。很可能，这两种蛋白质在单个胱抑素结构域的初次复制后发生了分化，因为α-2-HS-糖蛋白的两个胱抑素结构域彼此之间的相似性，尤其是在二硫键方面，比与激肽原的相应结构域的相似性更低。我们还提出，激肽原和α-2-HS-糖蛋白的羧基末端（非胱抑素）部分包含同源片段。我们认为α-2-HS-糖蛋白可能作为负责骨吸收的半胱氨酸蛋白酶的抑制剂发挥作用。我们还发现胎球蛋白与α-2-HS-糖蛋白密切相关。
