Ubiquitin–Proteasome System in the Induction and Maintenance of Cellular Pluripotency

Abstract Pluripotent embryonic stem cells (ESCs) are derived from preimplantation blastocysts and can differentiate into all types of somatic cells. More recently discovered induced pluripotent stem cells (iPSCs), which are derived from somatic cells via reprogramming and have characteristics similar to those of ESCs, represent another convenient model for studying the early embryonic development in mammals and hold a great promise for cell-based therapies of various diseases associated with cell and tissue dysfunction. Understanding mechanisms underlying self-renewal and differentiation of pluripotent stem cells, as well as the reprogramming of somatic cells to the pluripotent state, is of importance for efficient and safe introduction of these cells into clinics. One of the key molecular mechanisms underlying the regulation of cell activity is the regulation of protein degradation mediated by the ubiquitin-proteasome system (UPS). This review is devoted to the role and mechanisms of action of the UPS in the induction and maintenance of cellular pluripotency.