Raymond Adam, Ensslin Michael A, Shur Barry D
Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
J Cell Biochem. 2009 Apr 15;106(6):957-66. doi: 10.1002/jcb.22076.
MFG-E8 was initially identified as a principle component of the Milk Fat Globule, a membrane-encased collection of proteins and triglycerides that bud from the apical surface of mammary epithelia during lactation. It has since been independently identified in many species and by many investigators and given a variety of names, including p47, lactadherin, rAGS, PAS6/7, and BA-46. The acronym SED1 was proposed to bring cohesion to this nomenclature based upon it being a Secreted protein that contains two distinct functional domains: an N-terminal domain with two EGF-repeats, the second of which has an integrin-binding RGD motif, and a C-terminal domain with two Discoidin/F5/8C domains that bind to anionic phospholipids and/or extracellular matrices. SED1/MFG-E8 is now known to participate in a wide variety of cellular interactions, including phagocytosis of apoptotic lymphocytes and other apoptotic cells, adhesion between sperm and the egg coat, repair of intestinal mucosa, mammary gland branching morphogenesis, angiogenesis, among others. This article will explore the various roles proposed for SED1/MFG-E8, as well as its provocative therapeutic potential.
乳脂肪球表皮生长因子 8（MFG-E8）最初被鉴定为乳脂肪球的主要成分，乳脂肪球是一种由膜包裹的蛋白质和甘油三酯集合体，在哺乳期从乳腺上皮细胞的顶端表面芽生而出。此后，许多研究人员在许多物种中独立鉴定出了它，并赋予了它多种名称，包括 p47、乳粘连蛋白、rAGS、PAS6/7 和 BA-46。有人提出首字母缩写词 SED1，以使这个命名法统一起来，因为它是一种分泌蛋白，包含两个不同的功能域：一个带有两个表皮生长因子（EGF）重复序列的 N 端结构域，其中第二个 EGF 重复序列具有整合素结合 RGD 基序，以及一个带有两个盘状结构域/凝血因子 V/凝血因子 VIII C 结构域（Discoidin/F5/8C 结构域）的 C 端结构域，该结构域可与阴离子磷脂和/或细胞外基质结合。现在已知 SED1/MFG-E8 参与多种细胞相互作用，包括凋亡淋巴细胞和其他凋亡细胞的吞噬作用、精子与卵膜之间的黏附、肠黏膜修复、乳腺分支形态发生、血管生成等。本文将探讨 SED1/MFG-E8 所发挥的各种作用，以及其诱人的治疗潜力。
