Davies S M
Division of Pediatric Hematology, University of Minnesota, Minneapolis 55455.
Cancer Res. 1994 May 15;54(10):2560-2.
Control of the expression of the human insulin-like growth factor II gene is known to be complex, displaying both tissue-specific and developmental regulation. Insulin-like growth factor II is expressed at high levels in most tissues in the human fetus and appears to be important in fetal growth. In adult life, high levels of expression are found chiefly in liver, kidney, skin, nerve, and muscle tissue. Recent studies in the human fetus have demonstrated that in all tissues examined, including liver, the human insulin-like growth factor II gene is imprinted, with the paternally inherited allele expressed and the maternally inherited allele silent. The present study demonstrates that while the insulin-like growth factor gene is imprinted in human fetal liver, imprinting is relaxed in the second half of the first year of postnatal life, and thereafter the insulin-like growth factor gene is biallelically expressed.
已知人类胰岛素样生长因子II基因的表达调控很复杂，呈现出组织特异性和发育调控。胰岛素样生长因子II在人类胎儿的大多数组织中高水平表达，并且似乎对胎儿生长很重要。在成年期，高水平表达主要见于肝脏、肾脏、皮肤、神经和肌肉组织。最近对人类胎儿的研究表明，在所有检测的组织中，包括肝脏，人类胰岛素样生长因子II基因是印记基因，父本遗传的等位基因表达，母本遗传的等位基因沉默。本研究表明，虽然胰岛素样生长因子基因在人类胎儿肝脏中是印记基因，但在出生后第一年的后半期印记作用减弱，此后胰岛素样生长因子基因双等位基因表达。
