CHD7 regulates cardiac neural crest cell differentiation through SOX5-mediated self-activation

Area of Science:

• Developmental Biology
• Genetics
• Cardiovascular Research

Background:

• CHARGE syndrome is a complex genetic disorder associated with congenital heart defects.
• It is primarily caused by haploinsufficiency of the CHD7 gene.
• Cardiac neural crest cells (cNCCs) play a crucial role in heart development.

Purpose of the Study:

• To investigate the role of CHD7 in cardiac neural crest cell (cNCC) function.
• To elucidate the cellular mechanisms underlying CHARGE syndrome-associated heart defects.
• To identify potential therapeutic targets for cardiovascular abnormalities in CHARGE syndrome.

Main Methods:

• Single-cell RNA sequencing (scRNA-seq) analysis of cNCCs with Chd7 inactivation.
• Analysis of myogenic transcriptional programs and cell fate trajectories.
• Investigation of CHD7-SOX5 interactions and functional rescue experiments.

Main Results:

• Chd7 inactivation in cNCCs impairs myocyte differentiation by disrupting myogenic transcriptional programs.
• Loss of Chd7 leads to altered cell fate trajectories and activates cellular stress responses in cNCCs.
• CHD7 interacts with SOX5 to enhance its own expression via a conserved enhancer; SOX5 overexpression rescues Chd7 expression and cNCC differentiation.

Conclusions:

• CHD7 is essential for proper cNCC differentiation and function, with its loss contributing to heart defects in CHARGE syndrome.
• A SOX5-mediated autoregulatory mechanism controls CHD7 expression.
• Enhancing the SOX5-CHD7 axis presents a potential therapeutic strategy for cardiovascular defects in CHARGE syndrome.