Determination of the relationship between c-Abl protein tyrosine kinase and yap in cell fate determination during mouse preimplantation embryonic development

The successful completion of polarization, compaction and lineage specification is required for the development of embryo from the zygote to the blastocyst during preimplantation embryonic development. c-Abl (Abelson Tyrosine Kinase) is a non- receptor tyrosine kinase localized in cell nucleus and cytoplasm and also capable of nuclear-cytoplasmic shuttling. Despite the established knowledge regarding the YAP1 phosphorylation by c-Abl is very important for selective activation ofp73, the involvement of the c-Abl/YAP/p73 mechanism in embryonic development remains unexplored. The aim of thesis is investigate the functional role of c-Abl tyrosine kinase in polarization, compaction and cell fate determination through c-Abl/YAP/p73 cascade during early mouse embryonic development. C57BL6 female mice at 6-8-wk old were superovulated with 7,5 IU PMSG and after 48 hr 7,5 IU hCG, then mated. 20 hours after hCG enjection, zygotes were collected and cultured. We designed mainly 4 groups: Control group, PDGF-AA treatment group, imatinib treatment group, and c-Abl siRNA microinjection group. Morphological and morphokinetic parameters, blastomere area measurements, and apoptotic bodies were evaluated in embryos obtained from all experimental groups. We used immunofluorescence staining to determine localization of c-Abl, YAP, p-c-Abl, p-YAP, p73, TEAD4, Pard6, E-cadherin, CDX2 and NANOG by using confocal microscope. We detected c-Abl, Yap, trophoectodermal cell markers Tead and Cdx2 and inner cell markers Oct4 and Nanog expression at the mRNA levels using the qRT-PCR. In this thesis, we suggested for the first time c-Abl/YAP/p73 pathway served as a mechanism during mouse early embryonic development. The results contributes with new knowledge concerning the c-Abl tyrosine kinase may have regulative function in morphokinetic and morphodynamic features of mouse embryo in polarization, compaction, and cell fate specification during preimplantation embryonic development. This study was supported by Yeditepe University Research Projects and Scientific Activities Support Commission (Project No: YAP-AP-SAB-21019).