Rtf1 Transcriptionally Regulates Neonatal and Adult Cardiomyocyte Biology.

Area of Science:

• Molecular Biology
• Cardiovascular Biology
• Developmental Biology

Background:

• The PAF1 complex component Rtf1 is a transcription regulatory protein.
• Rtf1 is essential for cardiac progenitor specification during embryogenesis.
• The role of Rtf1 in mature cardiomyocytes is currently unknown.

Purpose of the Study:

• To investigate the function of Rtf1 in neonatal and adult cardiomyocytes.
• To determine the consequences of Rtf1 loss in cardiac cells.

Main Methods:

• Knockdown and knockout approaches were used in neonatal and adult mouse cardiomyocytes.
• Cardiac cell morphology, sarcomere integrity, cell-cell junctions, and cardiac function were assessed.

Main Results:

• Loss of Rtf1 in neonatal cardiomyocytes caused disrupted cell morphology and sarcomere breakdown.
• Rtf1 ablation in adult cardiomyocytes led to myofibril disorganization, junction disruption, fibrosis, and systolic dysfunction.
• Rtf1 knockout hearts showed dilated cardiomyopathy-like defects and altered cardiac gene expression.

Conclusions:

• Rtf1 is continuously required for maintaining the cardiac gene program and cardiomyocyte integrity.
• Rtf1 plays a vital role in both early cardiac development and the function of mature heart cells.
• Rtf1 deficiency results in progressive cardiac dysfunction and heart failure.