Coe J E, Vomachka A J, Ross M J
Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840, USA.
Proc Soc Exp Biol Med. 1999 Sep;221(4):369-75. doi: 10.1046/j.1525-1373.1999.d01-94.x.
Pentraxins such as human serum amyloid P component (SAP) and C reactive protein (CRP) represent an ancient family of proteins that are ubiquitous in nature and have evolved with little change in structure or regulation. The pentraxin in the Syrian hamster (Mesocricetus auratus) is unique because it is preferentially expressed in the female at high constitutive levels and accordingly called female protein (FP) or FP(SAP) due to its close homology with human SAP. The high levels of FP in female serum (100-fold greater than male serum) suggested its role in hamster pregnancy, one of the shortest of any eutherian mammal. We determined the serum FP concentration in pregnant Syrian hamsters and found a marked decrease (>80%) at term with the nadir at parturition with subsequent increase. A similar downregulation of FP was found in the normal female Syrian hamster after injury (acute phase response), so in both cases the assumed beneficial effects were achieved with less, rather than more pentraxin, a paradoxical pentraxin response. The fall in serum FP concentration could represent a response to protect the fetus from the high and potentially toxic level of FP normally found in the female, that is harmful because of its association with amyloidosis. An FP that is 97.5% identical to Syrian hamster FP is found in the Turkish hamster (Mesocricetus brandti), although serum levels in females are much lower, and amyloid is very rare. During pregnancy/parturition of Turkish hamsters, the serum level of FP remained remarkably constant. In a more distantly related hamster, the Armenian hamster (Cricetulus migratorius), serum FP actually increased during pregnancy and at parturition in a manner similar to that found in the Armenian hamster during an acute phase response. The heterogeneity of FP kinetics during pregnancy in these three species of hamster indicates pleomorphic gene structure for regulation of their similar FPs, and suggests that this protein may have a different function in the pregnancy of each species.
诸如人血清淀粉样蛋白P成分（SAP）和C反应蛋白（CRP）等五聚体蛋白代表了一类古老的蛋白质家族，它们在自然界中广泛存在，并且在结构或调节方面几乎没有变化地进化。叙利亚仓鼠（Mesocricetus auratus）中的五聚体蛋白是独特的，因为它在雌性中以高水平组成性表达，因此由于其与人SAP的密切同源性而被称为雌性蛋白（FP）或FP（SAP）。雌性血清中FP的高水平（比雄性血清高100倍）表明其在仓鼠妊娠中的作用，仓鼠妊娠是所有真兽类哺乳动物中最短的之一。我们测定了怀孕叙利亚仓鼠的血清FP浓度，发现在足月时显著下降（>80%），在分娩时达到最低点，随后升高。在正常雌性叙利亚仓鼠受伤后（急性期反应）也发现了类似的FP下调，所以在这两种情况下，假定的有益效果是通过较少而非较多的五聚体蛋白实现的，这是一种矛盾的五聚体蛋白反应。血清FP浓度的下降可能代表一种反应，以保护胎儿免受雌性中通常存在的高水平且可能有毒的FP的影响，这种FP因其与淀粉样变性的关联而有害。在土耳其仓鼠（Mesocricetus brandti）中发现了一种与叙利亚仓鼠FP有97.5%相同的FP，尽管雌性中的血清水平要低得多，并且淀粉样蛋白非常罕见。在土耳其仓鼠的妊娠/分娩期间，FP的血清水平保持显著恒定。在亲缘关系更远的仓鼠——亚美尼亚仓鼠（Cricetulus migratorius）中，血清FP在妊娠和分娩期间实际上以类似于亚美尼亚仓鼠在急性期反应期间发现的方式增加。这三种仓鼠在妊娠期间FP动力学的异质性表明调节其相似FP的基因结构具有多态性，并表明这种蛋白质在每个物种的妊娠中可能具有不同的功能。
