Differential expression of protein disulfide isomerase (PDI) in regulating endometrial receptivity in humans.

Estrogen and progesterone regulate the expression of endometrial proteins that determine endometrial receptivity for embryo implantation. The protein disulfide isomerase (PDI) family of proteins play a diverse role in regulating protein modification and redox function. Although the role of PDIs in cancer progression has been widely studied, their role in endometrial receptivity is largely unknown.

MicroRNA Let-7a and dicer are important in the activation and implantation of delayed implanting mouse embryos.

Study Question: Does Let-7a have a functional role in modulating dicer expression to activate dormant mouse blastocysts for implantation?

Summary Answer: Let-7a post-transcriptionally regulates dicer expression altering microRNA expression to affect the implantation competency of the activated blastocysts.

What Is Known Already: The Let-7a microRNA is up-regulated during blastocyst dormancy and its forced-expression suppresses embryo implantation in vitro and in vivo. Dicer is a Let-7 target, which processes pre-microRNA to mature microRNA.