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Assembly and architecture of biogenesis of lysosome-related organelles complex-1 (BLOC-1).

ABSTRACT: BLOC-1 (biogenesis of lysosome-related organelles complex-1) is critical for melanosome biogenesis and has also been implicated in neurological function and disease. We show that BLOC-1 is an elongated complex that contains one copy each of the eight subunits pallidin, Cappuccino, dysbindin, Snapin, Muted, BLOS1, BLOS2, and BLOS3. The complex appears as a linear chain of eight globular domains, ?300 Å long and ?30 Å in diameter. The individual domains are flexibly connected such that the linear chain undergoes bending by as much as 45°. Two stable subcomplexes were defined, pallidin-Cappuccino-BLOS1 and dysbindin-Snapin-BLOS2. Both subcomplexes are 1:1:1 heterotrimers that form extended structures as indicated by their hydrodynamic properties. The two subcomplexes appear to constitute flexible units within the larger BLOC-1 chain, an arrangement conducive to simultaneous interactions with multiple BLOC-1 partners in the course of tubular endosome biogenesis and sorting.

SUBMITTER: Lee HH

PROVIDER: S-EPMC3285357 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Assembly and architecture of biogenesis of lysosome-related organelles complex-1 (BLOC-1).

Lee Hyung Ho HH Nemecek Daniel D Schindler Christina C Smith William J WJ Ghirlando Rodolfo R Steven Alasdair C AC Bonifacino Juan S JS Hurley James H JH

The Journal of biological chemistry 20111227 8

BLOC-1 (biogenesis of lysosome-related organelles complex-1) is critical for melanosome biogenesis and has also been implicated in neurological function and disease. We show that BLOC-1 is an elongated complex that contains one copy each of the eight subunits pallidin, Cappuccino, dysbindin, Snapin, Muted, BLOS1, BLOS2, and BLOS3. The complex appears as a linear chain of eight globular domains, ∼300 Å long and ∼30 Å in diameter. The individual domains are flexibly connected such that the linear ...[more]

PMID: 22203680

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Dataset Information

Assembly and architecture of biogenesis of lysosome-related organelles complex-1 (BLOC-1).

Publications

Assembly and architecture of biogenesis of lysosome-related organelles complex-1 (BLOC-1).

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