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BORC assemblies integrate BLOC-1 subunits to diversify endosomal trafficking functions

ABSTRACT: BORC and BLOC-1, evolutionarily conserved since the last eukaryotic common ancestor, orchestrate endocytic trafficking. We show that the 3D architecture of BORC - two tetramers of intertwined α-helices with N-termini converging at the core - is conserved across species. Integrative structural approaches identified assembly-critical residues and elucidated disease mutation mechanisms. Strikingly, BORC and BLOC-1 components integrate into common complexes, with BORC-disrupting mutations also impairing BLOC-1 specific components incorporation. Crosslinking mass spectrometry analysis confirmed the in vivo presence of one BORC/BLOC-1 module. EARP subunits interact with BORC/BLOC-1 mixed complexes, suggesting that a subset of the hybrid assemblies regulates recycling. These findings challenge the view of BORC and BLOC-1 as distinct entities and instead support context-dependent assembly. We propose that dynamic, modular configurations enable specialized trafficking roles.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human) Caenorhabditis Elegans

SUBMITTER: Leopold Kremser

LAB HEAD: Lukas Alfons Huber

PROVIDER: PXD069550 | Pride | 2026-01-07

REPOSITORIES: Pride

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			Action	DRS
	10_Myrlysin_20proz.raw	Raw
	11_Lyspersin_20proz.raw	Raw
	12_Diaskedin_20proz.raw	Raw
	13_MEF2BNB_20proz.raw	Raw
	14_BLOC1S1_20proz.raw	Raw

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