RNA-Binding Protein Trim71 Controls Epicardial Cell Migration.

Area of Science:

• Developmental biology
• Molecular biology
• Cardiovascular research

Background:

• The epicardium is crucial for heart development, supplying cells and signals for growth and vessel formation.
• The transition from proepicardium (PE) to embryonic epicardium (EE) involves coordinated cell proliferation, migration, and lineage priming.
• Molecular mechanisms governing this developmental timing are not fully understood.

Purpose of the Study:

• To identify key regulators of epicardial cell behavior during the PE-to-EE transition.
• To elucidate the molecular mechanisms controlling the timing of epicardium development.

Main Methods:

• Identification of Trim71 as a key regulator.
• Functional analyses of Trim71 loss-of-function.
• Investigation of the feedback loop between Trim71 and microRNAs (let-7c, miR-30c).

Main Results:

• Trim71 is enriched in the PE and downregulated during migration.
• Loss of Trim71 decreases proliferation but enhances migration and induces epicardial commitment markers.
• Trim71 acts as a temporal gatekeeper, balancing progenitor maintenance and migration.
• A reciprocal feedback loop between Trim71 and let-7c/miR-30c was identified.

Conclusions:

• Trim71 is a critical regulator of epicardial progenitor cell behavior during early heart development.
• The Trim71-miRNAs axis represents a novel post-transcriptional regulatory mechanism for timely epicardium development.
• This study provides insights into the molecular control of cardiogenesis.