Genome-Wide CRISPR Screen Identifies an NF2-Adherens Junction Mechanistic Dependency for Cardiac Lineage

Area of Science:

• Stem cell biology
• Developmental biology
• Molecular biology

Background:

• Cardiomyocyte differentiation requires clearing repressors and regulators via BMP/Wnt signaling.
• Mechanisms of regulatory roadblock removal in cardiac development are unclear.

Purpose of the Study:

• Identify essential regulators of cardiomyocyte specification in human embryonic stem cells.
• Elucidate the role of NF2 in early cardiac lineage specification.

Main Methods:

• Genome-wide CRISPR screen using an MYH6-GFP reporter in human embryonic stem cells.
• NF2 knockout generation and analysis via RNA sequencing and protein expression.
• In vitro differentiation models and protein interaction assays.

Main Results:

• NF2 is an upstream driver of early cardiomyocyte specification.
• NF2 loss causes loss of cardiomyocyte identity and gain of non-mesodermal identity.
• NF2 and AMOT prevent YAP activation by forming a scaffold complex at adherens junctions.

Conclusions:

• NF2 is essential for removing regulatory roadblocks during cardiomyocyte differentiation.
• NF2 sequesters YAP's repressive effect, facilitating epithelial-mesenchymal transition towards cardiomyocytes.