Brachyury co-operates with polycomb protein RYBP to regulate gastrulation and axial elongation .

Early embryonic development is a complex process where undifferentiated cells lose their pluripotency and start to gastrulate. During gastrulation, three germ layers form, giving rise to different cell lineages and organs. This process is regulated by transcription factors and epigenetic regulators, including non-canonical polycomb repressive complex 1s (ncPRC1s).

Polycomb protein RYBP activates transcription factor during cardiac differentiation of mouse embryonic stem cells.

RING1 and YY1 binding protein (RYBP) is primarily known to function as a repressor being a core component of the non-canonical polycomb repressive complexes 1 (ncPRC1s). However, several ncPRC1-independent functions of RYBP have also been described. We previously reported that RYBP is essential for mouse embryonic development and that null mutant embryonic stem cells cannot form contractile cardiomyocytes (CMCs) .

RYBP regulates Pax6 during in vitro neural differentiation of mouse embryonic stem cells.

We have previously reported that RING1 and YY1 binding protein (RYBP) is important for central nervous system development in mice and that Rybp null mutant (Rybp) mouse embryonic stem (ES) cells form more progenitors and less terminally differentiated neural cells than the wild type cells in vitro. Accelerated progenitor formation coincided with a high level of Pax6 expression in the Rybp neural cultures. Since Pax6 is a retinoic acid (RA) inducible gene, we have analyzed whether altered RA signaling contributes to the accelerated progenitor formation and impaired differentiation ability of the Rybp cells.

RYBP is important for cardiac progenitor cell development and sarcomere formation.

We have previously established that epigenetic regulator RING1 and YY1 binding protein (RYBP) is required for the contractility of embryonic stem (ES) cell derived cardiomyocytes (CMCs), suggesting its essential role in contractility. In order to investigate the underlying molecular events of this phenotype, we compared the transcriptomic profile of the wild type and Rybp null mutant ES cells and CMCs differentiated from these cell lines. We identified genes related to ion homeostasis, cell adhesion and sarcomeric organization affected in the Rybp null mutant CMCs, by using hierarchical gene clustering and Gene Ontology analysis.

Lack of Rybp in Mouse Embryonic Stem Cells Impairs Cardiac Differentiation.

Ring1 and Yy1 binding protein (Rybp) has been implicated in transcriptional regulation, apoptotic signaling and as a member of the polycomb repressive complex 1, it has an important function in regulating pluripotency and differentiation of embryonic stem cells (ESCs). Earlier, we had proved that Rybp plays an essential role in mouse embryonic and central nervous system development. This work identifies Rybp, as a critical regulator of heart development.