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Constitutively active ESCRT-II suppresses the MVB-sorting phenotype of ESCRT-0 and ESCRT-I mutants.

ABSTRACT: The endosomal sorting complex required for transport (ESCRT) protein complexes function at the endosome in the formation of intraluminal vesicles (ILVs) containing cargo proteins destined for the vacuolar/lysosomal lumen. The early ESCRTs (ESCRT-0 and -I) are likely involved in cargo sorting, whereas ESCRT-III and Vps4 function to sever the neck of the forming ILVs. ESCRT-II links these functions by initiating ESCRT-III formation in an ESCRT-I-regulated manner. We identify a constitutively active mutant of ESCRT-II that partially suppresses the phenotype of an ESCRT-I or ESCRT-0 deletion strain, suggesting that these early ESCRTs are not essential and have redundant functions. However, the ESCRT-III/Vps4 system alone is not sufficient for ILV formation but requires cargo sorting mediated by one of the early ESCRTs.

SUBMITTER: Mageswaran SK

PROVIDER: S-EPMC4310745 | biostudies-other | 2015 Feb

REPOSITORIES: biostudies-other

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Constitutively active ESCRT-II suppresses the MVB-sorting phenotype of ESCRT-0 and ESCRT-I mutants.

Mageswaran Shrawan Kumar SK Johnson Natalie K NK Odorizzi Greg G Babst Markus M

Molecular biology of the cell 20141210 3

The endosomal sorting complex required for transport (ESCRT) protein complexes function at the endosome in the formation of intraluminal vesicles (ILVs) containing cargo proteins destined for the vacuolar/lysosomal lumen. The early ESCRTs (ESCRT-0 and -I) are likely involved in cargo sorting, whereas ESCRT-III and Vps4 function to sever the neck of the forming ILVs. ESCRT-II links these functions by initiating ESCRT-III formation in an ESCRT-I-regulated manner. We identify a constitutively activ ...[more]

PMID: 25501366

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