A coherent FOXO3-SNAI2 feed-forward loop in autophagy

Area of Science:

• Cell Biology
• Molecular Biology
• Genetics

Background:

• Autophagy is a critical cellular process implicated in various diseases.
• Understanding its regulation is key to developing targeted therapies.

Purpose of the Study:

• To identify novel regulators of autophagy through a genome-wide screen.
• To elucidate the molecular mechanisms by which identified regulators control autophagy.

Main Methods:

• Genome-wide screening in HeLa cells to identify autophagy regulators.
• Investigating the interaction between SNAI2 and FOXO3 using molecular biology techniques.
• Analyzing the effect on nuclear export and gene expression.

Main Results:

• SNAI2 was identified as a novel regulator of autophagy.
• SNAI2 and FOXO3 form a feed-forward regulatory loop, enhancing autophagy gene expression.
• SNAI2 promotes FOXO3 nuclear retention by increasing its DNA binding, inhibiting CRM1-dependent export.
• A conserved dFoxO-Snail loop regulates autophagy and cell size in Drosophila.

Conclusions:

• SNAI2 is a crucial regulator of autophagy, acting via a feed-forward loop with FOXO3.
• DNA binding plays a critical role in the nuclear retention of nucleocytoplasmic shuttling proteins like FOXO3.
• This conserved regulatory mechanism highlights potential therapeutic targets for autophagy-related disorders.