Precision autophagy directed by receptor regulators - emerging examples within the TRIM family

Area of Science:

• Cellular Biology
• Molecular Biology
• Autophagy Research

Background:

• Selective autophagy requires coordination between cargo recognition and autophagic machinery assembly.
• Receptors typically recognize tags like ubiquitin, but tag-independent pathways are emerging.
• The interaction between receptors and upstream regulators, beyond Atg8/LC3B, remains incompletely understood.

Purpose of the Study:

• To elucidate the molecular mechanisms of TRIM proteins in selective autophagy.
• To understand how TRIMs coordinate cargo recognition with the assembly and activation of core autophagy regulators.
• To define the role of TRIMs as 'receptor regulators' in autophagy.

Main Methods:

• Investigated the dual role of TRIM proteins as autophagy receptors and assembly platforms.
• Examined TRIMs' ability to directly recognize targets, bypassing traditional tags.
• Analyzed TRIMs' function in coordinating the assembly and activation of ULK1 and Beclin 1.

Main Results:

• TRIM proteins function as both receptors and platforms for autophagy regulators.
• TRIMs can directly bind to targets, independent of ubiquitin or galectin tags.
• TRIMs facilitate the assembly and activation of key autophagy components like ULK1 and Beclin 1.

Conclusions:

• TRIM proteins are crucial for coordinating cargo recognition and autophagosome formation.
• The dual receptor-regulatory function of TRIMs enables a precise form of autophagy.
• TRIMs represent a novel mechanism for targeted degradation, termed 'precision autophagy'.