Heat Shock Factor 2 Protects against Proteotoxicity by Maintaining Cell-Cell Adhesion

Area of Science:

• Cell Biology
• Molecular Biology
• Genetics

Background:

• Protein homeostasis is vital for cell survival, especially under proteotoxic stress.
• Heat shock factor 2 (HSF2) expression and DNA-binding activity increase with prolonged proteotoxicity.
• The specific roles of HSF2 and its gene expression profile during sustained stress were previously unknown.

Purpose of the Study:

• To investigate the critical roles of HSF2 in cell survival during prolonged proteotoxicity.
• To elucidate the global gene expression profile regulated by HSF2 under sustained stress.
• To determine the mechanisms by which HSF2 confers resistance to proteotoxic stress.

Main Methods:

• RNA sequencing (RNA-seq) was employed to analyze gene expression profiles in HSF2-deficient cells.
• Proteasome inhibition was used to induce proteotoxic stress.
• Cell viability assays were performed to assess the impact of HSF2 deficiency.

Main Results:

• HSF2 is essential for cell survival during prolonged proteotoxicity.
• HSF2 deficiency leads to the downregulation of cadherin superfamily genes, not impaired chaperone induction.
• HSF2-dependent maintenance of cadherin-mediated cell-cell adhesion protects against proteasome inhibitor-induced stress.

Conclusions:

• HSF2 is a key regulator of cadherin superfamily genes.
• Cadherin-mediated cell-cell adhesion is a critical determinant of resistance to proteotoxic stress.
• This study redefines the protective mechanisms of HSF2 beyond chaperone regulation.