Protein Trafficking or Cell Signaling: A Dilemma for the Adaptor Protein TOM1

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Lysosomal degradation of ubiquitinated transmembrane proteins requires Endosomal Sorting Complex Required for Transport (ESCRT) machinery.
• Target of Myb1 (TOM1) is an ESCRT protein crucial for early endosomal cargo sorting.
• TOM1 interacts with ubiquitin moieties via its VHS and GAT domains.

Purpose of the Study:

• To review the multifaceted roles of TOM1 in cellular processes.
• To elucidate TOM1's coordination with protein partners in physiological and pathological contexts.
• To highlight TOM1's involvement in autophagy, immune responses, and neuroinflammation.

Main Methods:

• Literature review of existing studies on TOM1 function.
• Analysis of TOM1's interactions with other ESCRT proteins (e.g., TOLLIP, Endofin, Hrs).
• Exploration of TOM1's role in non-canonical pathways like autophagy and immunity.

Main Results:

• TOM1 functions in initial endosomal cargo sorting by binding ubiquitin.
• TOM1 forms complexes with other ESCRT proteins at early endosomes.
• TOM1 is implicated in autophagy, immune responses, and neuroinflammation.

Conclusions:

• TOM1 plays a central role in endosomal sorting and lysosomal degradation.
• TOM1's functions extend beyond cargo sorting, impacting broader cellular pathways.
• Dysregulation of TOM1 is linked to bacterial infections, cancer progression, and neuroinflammation.