Dynamics of Maternal Survivin mRNA in Mouse Oocytes and Pre-implantation Embryos

Survivin is a bi-functional protein which has been shown to suppress apoptosis and regulate cell division in mammalian carcinoma cell lines and some somatic cells. In previous studies, we showed that survivin is an essential anti-apoptotic gene which is expressed in mouse pre-implantation embryos, and found that embryos in which survivin has been disrupted develop only to the blastocyst stage. Based on what is known about survivin in mammals and other organisms, we proposed that maternal survivin mRNA may be required for oocyte maturation and early embryonic development, including a role in regulation of chromosome segregation. To test this, we assessed changes in survivin mRNA levels over time in mouse oocytes and embryos, and asked if survivin mRNA levels change in a cell cycle-dependent manner in mouse oocytes and embryos. We found that maternal survivin mRNA levels were higher than zygotically transcribed survivin mRNA levels in mouse preimplantation embryos, that zygotic survivin was regulated in a cell-cycle dependent manner, and that survivin mRNA levels were high in young mouse oocytes but decreased as mice aged. Our data suggest that survivin may play a role as a maternal gene in the development of mouse oocytes and pre-implantation embryos.