Anthricin-induced hyperactive proteasome and its molecular mechanism

Area of Science:

• Biochemistry
• Molecular Biology
• Drug Discovery

Background:

• Targeted protein degradation is a promising drug discovery strategy.
• Proteasome activity modulation is of significant interest.
• Anthricin, a lignan, was previously shown to enhance proteasome activity.

Purpose of the Study:

• To elucidate the mechanism by which anthricin enhances proteasome activity.
• To investigate the structure-activity relationship of anthricin analogs.
• To explore anthricin's direct interaction with the proteasome.

Main Methods:

• Structure-activity relationship analysis of anthricin analogs.
• Assessment of anthricin's effect on proteasome-related gene expression.
• Pull-down assays to detect direct binding.
• Molecular dynamics simulations to model interactions.

Main Results:

• Anthricin does not alter proteasome-related gene expression.
• Anthricin directly binds to the proteasome's β-subunit.
• Binding induces a hyperactive state by repositioning catalytic site residues.
• MD simulations confirmed the binding interaction.

Conclusions:

• Anthricin enhances proteasome activity via direct molecular interaction, not gene expression.
• This study reveals the molecular mechanism of anthricin-induced proteasome hyperactivity.
• Findings support developing new compounds to modulate proteasome activity for targeted protein degradation.