The repressor element 1-silencing transcription factor regulates heart-specific gene expression using multiple...

Area of Science:

• Molecular biology
• Cardiovascular science
• Gene regulation

Background:

• Cardiac hypertrophy involves altered gene expression, reexpressing fetal genes.
• The transcriptional repressor REST (repressor element 1-silencing transcription factor) is implicated in repressing fetal genes in adult hearts.

Purpose of the Study:

• To elucidate the molecular mechanisms by which REST represses fetal gene expression in cardiac hypertrophy.

Main Methods:

• Investigated REST's effect on BNP (Nppb) and ANP (Nppa) gene expression in adult rat ventricular myocytes and H9c2 cells.
• Analyzed histone modifications (acetylation, methylation) at gene promoter regions.
• Utilized deletion mutants of REST repression domains to assess their role in gene repression.

Main Results:

• Continued REST expression inhibited endothelin-1-induced Nppb and Nppa gene increases.
• REST inhibition led to increased Nppb and Nppa expression, correlating with histone H4 acetylation and H3K4 methylation.
• Two REST repression domains are needed for efficient Nppb repression, while one suffices for Nppa repression.

Conclusions:

• REST plays a crucial role in preventing fetal gene reexpression during cardiac hypertrophy.
• Specific REST domains differentially regulate Nppb and Nppa gene transcription.
• Provides novel insights into the molecular mechanisms underlying gene expression changes in cardiac hypertrophy.