Angiomotin Regulates YAP Localization during Neural Differentiation of Human Pluripotent Stem Cells

Abstract

Summary: Leveraging the extraordinary potential of human pluripotent stem cells (hPSCs) requires an understanding of the mechanisms underlying cell-fate decisions. Substrate elasticity can induce differentiation by signaling through the transcriptional coactivator Yes-associated protein (YAP). Cells cultured on surfaces mimicking brain elasticity exclude YAP from their nuclei and differentiate to neurons. How YAP localization is controlled during neural differentiation has been unclear. We employed CRISPR/Cas9 to tag endogenous YAP in hPSCs and used this fusion protein to identify YAP's interaction partners. This engineered cell line revealed that neural differentiation promotes a change in YAP interactors, including a dramatic increase in angiomotin (AMOT) interaction with YAP. AMOT regulates YAP localization during differentiation. AMOT expression increases during neural differentiation and leads to YAP nuclear exclusion. Our findings that AMOT-dependent regulation of YAP helps direct hPSC fate provide insight into the molecular mechanisms by which the microenvironment can induce neural differentiation. : Kiessling and colleagues employed CRISPR/Cas9 to generate an hPSC line in which YAP is tagged, thus facilitating affinity purification of endogenous-level YAP complexes for analysis. This strategy uncovered proteins that interact with YAP during self-renewal and differentiation and identified angiomotin as a key regulator of YAP localization during neural differentiation. Keywords: YAP, mechanosensing, neuronal differentiation, angiomotin, human pluripotent stem cells, embryonic stem cells, neural progenitor cells, ubiquitination, CRISPR genome engineering, proteomics