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.
STUDY DESIGN, SIZE, DURATION
The effects on the expression of Let-7a and dicer in dormant blastocysts during the first 12 h after estradiol-induced activation, and the relationship between Let-7a and dicer in preimplantation embryos were determined. The effects on the microRNA expression and embryo implantation in vivo in dicer-knockdown mouse 5–8 cell embryos and dormant blastocysts at 1 h post estradiol activation were also studied.
PARTICIPANTS/MATERIALS, SETTING, METHODS
ICR female mice at 6 weeks of age were ovariectomized on Day 4 of pregnancy to generate the delayed implantation model. Mouse 5–8 cell embryos and/or dormant blastocysts at 1 h after estradiol injection were electroporated with dicer siRNA and Let-7a precursor or Let-7a inhibitor. At 48 h post electroporation, the Let-7a expression, dicer transcripts and proteins in the embryos were determined using qPCR and immunostaining/western blotting, respectively. A...
Source: Human Reproduction - Category: Reproduction Medicine Authors: Cheong, A. W. Y., Pang, R. T. K., Liu, W.-M., Kottawatta, K. S. A., Lee, K.-F., Yeung, W. S. B. Tags: Reproductive biology Source Type: research