Autophagy and multivesicular body formation in blastocysts during the experimental diapause in mice

In experimentally induced diapause model in mice, blastocysts remain dormant for an extended period but resume implantation competency upon estrogen injection. The underlying mechanism by which extended longevity of dormant blastocysts is maintained is unclear. We have previously shown that dormant blastocysts, during experimentally induced diapause, exhibit heightened autophagic activation. Activation of autophagy appears to be a crucial adaptive response for survival in the unfavorable uterine environment, as inhibiting autophagy reduces the survival rate of dormant blastocysts. As a unique cell biological change occurring following estrogen supplementation to activate dormant blastocysts, multivesicular bodies (MVBs) accumulate in the trophectoderm. In various cellular contexts, autophagy and MVB formation are linked cell biological phenomena. Herein, we discuss the implications of these cell biological changes in dormant and activated blastocysts.