Δημήτριος Λουτράδης, Καθηγητής, Ιατρική, ΕΚΠΑ
Πέτρος Δρακάκης, Αναπληρωτής Καθηγητής, Ιατρική, ΕΚΠΑ
Αικατερίνη Ντόμαλη , Επίκουρη Καθηγήτρια, Ιατρική, ΕΚΠΑ
In mammals, the fertilization occurs in the ampulla of the falloplan tube and completed after the coalescence of the female and the male pronucleus. Resulting in zygote. Subsequently, in the pre-implantation period, in which the zygote undergoes many structular changes. More specific, the fertilized ovum is divided into 2,4 and 8 cells, following the coalescence with the blastomere compression and tha maximization of their intercellular contacts. From coalescence to the 32 cells stage tha embryo is called morula. Three days after the fertilization, the embryos ‘’falls’’ from the ovary, ‘’travels’’ to the uterus and inside of the embryo starts the formation of the blastocilium and the embryos is called blastocyst.
In stage 4 to 8 cells, starts the production of specific proteins (the first two division are passive). That explains the significance of studying this stage of embryonic evolutionary procedure.
Faithful DNA replication and trancription is essential for the maintenance of genome integrity. Incomplete genome replication leads to chromosomal rearrangements, which are causal factors in cancer and other human diseases. Despite their importance, the molecular mechanisms that control human genome stability are incompletely understood.
RBBP6 gene is located in chromosome 16 (16ρ12-ρ11.2) in the human genome while in the mus musculus is in chromosome 7. RBBP6 protein has been intentified as an E3 ligase oubiquitin, mainly because of the ‘’RING’’ domain.
The location in which protein is connected with Rb and p53 are responsible for their interaction. These interactions play a very significant role has a very significant role in the apoptosis and in the regulation of cell cycle.
Also, the catalityc action of RBBP6 in the deconstructiom through proteosoma is very important because through this mechanism resulting the deconstruction of maternal mRNAs. During the activation of the embryonic genome. Probably, the absence or the low expression of the gene, delays or stops the deconstruction of the maternal genome with dangerous consiquences for the evolution development of the embryo.
In this study, the expression of the RBBP6 gene in mouse precursors in the 8 cell stage is compared with the expression of the gene in apoptotic embryos. The purpose of this procedure is to identify the potential molecular and cellular mechanisms associated with a normal embryonic development. Furthermore, the aim is to correlate the expression of the RBBP6 gene with the quality of the embryos.
Overall, 81 embryos were obtained from female mice, of which 18 embryos reached 8 cells and the 63 embryos were isolated from them. Subsequently, total RNA was isolated from the embryonic cells, followed by cDNA synthesis, and finally the study of RBBP6 gene expression by the Real Time PCR method.
According, to the results of this study, the RBBP6 gene is expressed in the apoptotic embryos and embryos in stage of 8 cells. In embryos in stage of 8 cells the expression is higher than offthose in apoptotic embryos. The understanding of the mechanism that follows the activation and the expression of embryonic genome, througt the study of expression of genes and because of the inaction of some others would be a significant indicator of viability of embryos and evolution of IVF.