{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nMARCH proteins comprise a family of transmembrane ubiquitin ligases that play essential roles in regulating the trafficking and turnover of cell surface proteins. Although the abstract provided focuses on MARCH‐VIII and MARCH‐IV, the findings offer insight applicable to other family members such as MARCHF4. These enzymes mediate intracellular protein sorting by catalyzing the ubiquitination of transmembrane proteins, which in turn influences their intracellular localization and degradation."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn the study, MARCH‐VIII was shown to diminish the plasma membrane expression of several proteins. Notably, it reduced the levels of Bap31—a chaperone mostly resident in the endoplasmic reticulum—while also lowering the surface presence of the hyaluronic acid receptor CD44. Additionally, both MARCH‐VIII and MARCH‐IV sequestered the tetraspanin CD81 within endo‐lysosomal compartments. Such findings indicate that MARCH proteins direct the cellular fate of their substrates by controlling both their trafficking routes and their turnover."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nThese results underscore a broader regulatory role for MARCH family members, including MARCHF4, suggesting that they contribute to the maintenance of cell surface composition and receptor turnover. The observed functional interplay with chaperones such as Bap31 supports a model wherein interactions with specific partners are crucial for the proper intracellular routing of MARCH proteins and their substrates. Thus, by modulating key signaling and adhesion molecules, MARCH proteins help ensure dynamic control over cellular responses and homeostasis."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Eric Bartee, Craig A Eyster, Kasinath Viswanathan, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Membrane-Associated RING-CH proteins associate with Bap31 and target CD81 and CD44 to lysosomes."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "PLoS One (2010)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1371/journal.pone.0015132"}], "href": "https://doi.org/10.1371/journal.pone.0015132"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "21151997"}], "href": "https://pubmed.ncbi.nlm.nih.gov/21151997"}]}]}]}