Yadav S, Garrido A, Hernández MC, Oliveros JC, Pérez-García V, Fraga MF, Carrera AC. PI3Kβ-regulated β-catenin mediates EZH2 removal from promoters controlling primed human ESC stemness and primitive streak gene expression.
Stem Cell Reports 2022;
17:2239-2255. [PMID:
36179694 PMCID:
PMC9561645 DOI:
10.1016/j.stemcr.2022.09.003]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/21/2022] Open
Abstract
The mechanism governing the transition of human embryonic stem cells (hESCs) toward differentiated cells is only partially understood. To explore this transition, the activity and expression of the ubiquitous phosphatidylinositol 3-kinase (PI3Kα and PI3Kβ) were modulated in primed hESCs. The study reports a pathway that dismantles the restraint imposed by the EZH2 polycomb repressor on an essential stemness gene, NODAL, and on transcription factors required to trigger primitive streak formation. The primitive streak is the site where gastrulation begins to give rise to the three embryonic cell layers from which all human tissues derive. The pathway involves a PI3Kβ non-catalytic action that controls nuclear/active RAC1 levels, activation of JNK (Jun N-terminal kinase) and nuclear β-catenin accumulation. β-Catenin deposition at promoters triggers release of the EZH2 repressor, permitting stemness maintenance (through control of NODAL) and correct differentiation by allowing primitive streak master gene expression. PI3Kβ epigenetic control of EZH2/β-catenin might be modulated to direct stem cell differentiation.
PI3Kβ directs epigenetic control of stemness and primitive streak (PS) essential genes
PI3Kβ directs RAC1/JNK/β-catenin activation and induces EZH2 promoter displacement
β-Catenin/EZH2 control NODAL, a gene essential for stemness and the master PS genes
PI3Kβ/PI3K activities cooperate at stemness; PI3Kβ directs PS gene expression
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