Progesterone-regulated gene expression in the primate endometrium

Progesterone action is essential for maturation of the endometrium to a rec eptive state for implantation in humans and nonhuman primates. The orchestr ation of progesterone-regulated gene expression is also temporally controll ed during the secretory phase based on the limited window for implantation. The genes and gene networks affected by progesterone are likely to involve both activation and repression. Our laboratory has used the rhesus monkey as a model to study the regulation of genes known or suspected to be involv ed in endometrial maturation. In addition, we have used subtractive hybridi zation and differential display techniques to identify novel or unsuspected genes that are regulated by progesterone during endometrial maturation. Ou r studies have led us to propose a working model of progesterone action dur ing the primate secretory phase that includes waves of gene activation and repression that culminate in a receptive endometrium.