Year: 2016
Type: dissertation
Abstract: Platelets play a key role in vascular homeostasis by triggering platelet adhesion, aggregation, and release of cargo from secretory granules. Inherited defects in α-granule cargo sorting and packaging in platelet precursor megakaryocytes (MKs) include arthrogryposis, renal dysfunction and cholestasis (ARC) syndrome, which is characterized by mutations in VPS33B or VPS16B. In this study, components of the multisubunit tethering complex, GARP/EARP, and an endosomal transport complex, CCC, were identified as potential interacting partners for VPS33B/VPS16B using a BioID screen and mass spectrometry. These interactions were confirmed and characterized via immunoprecipitation experiments, and immunofluorescence microscopy studies of megakaryocytic cell lines (Dami, imMKCL) revealed that subunits of the GARP/EARP and CCC complexes co-localize with markers of the trans-Golgi Network, late endosomes and α-granules. These findings suggest a role for previously unsuspected interactions of GARP/EARP, CCC and VPS33B/VPS16B complexes in α-granule biogenesis by regulating intracellular membrane fusion in a coordinated nature.
Source: TSpace (University of Toronto)
Author: Chang‐Hua Chen
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2600885775