Naslov
Late endosomal trafficking and endosecretory recycling route of open MHC-I conformers

Autori
Mahmutefendić, Hana ; Blagojević Zagorac G, Gordana ; Grabušić, Kristina ; Karleuša, Ljerka ; Momburg, Frank ; Lučin, Pero

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Abstract book / - , 2015, 246-247

Skup
4th European Congress of Immunology - ECI 2015

Mjesto i datum
Beč, Austrija, 06.09.2015. - 09.09.2015

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
opem MHC-I conformers; late endosomes; endocytosis

Sažetak
Open Major Histocompatibility Class I (MHC-I) conformers are cell surface proteins that segregate from fully conformed MHC-I proteins at the cell surface and travel late endosomal (LE) route after constitutive endocytic uptake. In this work, we have characterized LE trafficking route of open Ld molecules (empty Ld) in murine fibroblast-like cells. By using confocal microscopy, we have demonstrated that empty Ld enter the major Rab7-/NPC1-positive LE network either via Rab9-positive early late endosomes (LEs), together with M6PR, or via MLN64-positive early LEs, together with degradative cargo. In the major LE network empty Ld segregate into specific pre-degradative subset of LEs and enter either into degradative route or into endosecretory route and recycle back to the cell surface. The half-life of internalized empty Ld molecules is about 45-60 minutes (detected by flow cytometry or western blot analysis after surface biotynilation). That implies that molecules could be retained in endosomes. A fraction of empty Ld is segregated into the subset of endosecretory organelles that is distinct from exosome-generating endosecretory carriers. Segregation of empty Ld into degradative endosomes and degradation requires Rab7 and vectoral LE motility, whereas segregation into endosecretory carriers and recycling requires vectorial LE movements and cholesterol unloading but not Rab7. Thus, our analysis of empty Ld LE trafficking reveals endosecretory route and LE recycling of a plasma membrane protein. Analysis of LE eLd trafficking contributes to the understanding of the complexity of LE subsets and LE sorting, conformation based sorting in the endosomal system and the pathways of endosomal antigen-presentation.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

POVEZANOST RADA