Prolactin receptor ligands bind the prolactin receptor

Human PRLR binds at least 3 related peptide ligands namely prolactin, placental lactogen (PL) and growth hormone (GH). In non primates, GH is not able to bind the PRLR. Human GH binding to the PRLR is zinc-dependent (Cunningham et al. 1990). All three ligands bind the extracellular domain and have apparently identical actions. Two disulfide-linked cysteines in the D1 subdomain are involved in ligand binding while the WSXWS motif in the D2 subdomain is probably required for folding and cellular trafficking.

人源PRLR至少与三种相关肽类配体结合，即催乳素、胎盘催乳素（PL）和生长激素（GH）。在非灵长类动物中，GH无法与PRLR结合。人源GH与PRLR的结合依赖于锌离子（Cunningham等人，1990年）。这三种配体均与细胞外域结合，并表现出显然相同的效应。D1亚域中的两个二硫键连接的半胱氨酸参与配体结合，而D2亚域中的WSXWS基序可能对于蛋白质折叠和细胞运输是必需的。