Practice question

Pluripotency maintenance depends on integrated extrinsic pathways modulating core transcription factor circuitry of Oct4 and Nanog. Wnt beta-catenin signaling inhibits GSK3 beta, stabilizing beta-catenin which interacts with Oct4 and derepresses Nanog promoter, while also supporting metabolic reprogramming toward glycolysis. In mouse embryonic stem cells, Wnt together with LIF sustains ground state pluripotency in 2i culture medium containing CHIR99021 and PD0325901 MEK inhibitor. JAK-STAT downstream of LIF, Hedgehog, and Notch primarily regulate lineage-specific somatic stem cells, but Wnt activation more broadly stabilizes undifferentiated self-renewing state across species in vitro.