Baker M E, French F S, Joseph D R
Biochem J. 1987 Apr 1;243(1):293-6. doi: 10.1042/bj2430293.
Vitamin K-dependent protein S belongs to the family of clotting factors (e.g. Factors IX and X, and protein C). Unlike the other clotting factors, the C-terminal half (residues 250-634) of protein S is not a serine proteinase. In fact, the function of residues 250-634 of protein S is unknown. By using computer programs designed to detect evolutionary relationships between proteins, we find that this part of protein S is similar to rat androgen-binding protein, a protein produced and secreted by testicular Sertoli cells. The homology between protein S and androgen-binding protein suggests new approaches for elucidating their functions.
维生素K依赖的蛋白S属于凝血因子家族(如因子IX、因子X和蛋白C)。与其他凝血因子不同,蛋白S的C端一半(第250 - 634位氨基酸残基)不是丝氨酸蛋白酶。实际上,蛋白S第250 - 634位氨基酸残基的功能尚不清楚。通过使用旨在检测蛋白质之间进化关系的计算机程序,我们发现蛋白S的这一部分与大鼠雄激素结合蛋白相似,后者是睾丸支持细胞产生并分泌的一种蛋白质。蛋白S与雄激素结合蛋白之间的同源性为阐明它们的功能提供了新方法。