Document Detail


Dileucine signal-dependent and AP-1-independent targeting of a lysosomal glycoprotein in Trypanosoma brucei.
MedLine Citation:
PMID:  17869353     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Sorting of trans-membrane proteins destined for the lysosome is achieved by selective inclusion into post-Golgi transport vesicles. In higher eukaryotes sorting may be mediated by a peptidic motif, principally acidic clusters and tyrosine- or dileucine-based cytoplasmic signals or by inclusion of mannose-6-phosphate (M6P) into the N-glycans of lysosomal proteins. In African trypanosomes a major lysosomal trans-membrane protein is CB-1/p67. The cytoplasmic domain of p67 lacks tyrosine and lysine, but does contain a canonical dileucine sequence embedded within an acidic region. AP-1, -3 and -4 adaptin complexes, which recognise tyrosine- and dileucine-sorting signals, are encoded by the trypanosome genome, but the genes for M6P-receptors or activities required to produce M6P are absent, suggesting that lysosomal delivery of p67 is most likely adaptin-mediated. By construction of p67 reporter constructs we show that the dileucine signal is necessary and sufficient for efficient lysosomal delivery of a trans-membrane protein in bloodstream stage trypanosomes. However, this targeting does not require AP-1, as knockdown of the trypanosome gamma-adaptin subunit by RNAi has no detectable effect on the location or maturation of p67. These data suggest that p67 is targeted to the lysosome by dileucine-dependent but AP-1-independent mechanisms.
Authors:
Clare L Allen; Dangjin Liao; Wei-Lian Chung; Mark C Field
Related Documents :
14662743 - Yeast homotypic vacuole fusion requires the ccz1-mon1 complex during the tethering/dock...
8817003 - Multilamellar endosome-like compartment accumulates in the yeast vps28 vacuolar protein...
3049073 - Biogenesis of the yeast lysosome (vacuole): biosynthesis and maturation of proteinase y...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2007-08-06
Journal Detail:
Title:  Molecular and biochemical parasitology     Volume:  156     ISSN:  0166-6851     ISO Abbreviation:  Mol. Biochem. Parasitol.     Publication Date:  2007 Dec 
Date Detail:
Created Date:  2007-10-29     Completed Date:  2008-02-26     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8006324     Medline TA:  Mol Biochem Parasitol     Country:  Netherlands    
Other Details:
Languages:  eng     Pagination:  175-90     Citation Subset:  IM    
Affiliation:
The Molteno Building, Department of Pathology, Tennis Court Road, University of Cambridge, Cambridge CB2 1QP, UK.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Amino Acid Motifs
Animals
Artificial Gene Fusion
Genes, Reporter
Glycoproteins / chemistry,  genetics,  metabolism*
Lysosomes / metabolism*
Protein Sorting Signals / genetics*,  physiology*
Protein Transport
Protozoan Proteins / chemistry,  genetics,  metabolism
Trypanosoma brucei brucei / genetics,  metabolism*
Grant Support
ID/Acronym/Agency:
//Wellcome Trust
Chemical
Reg. No./Substance:
0/Glycoproteins; 0/Protein Sorting Signals; 0/Protozoan Proteins

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Optical fiber immunosensor for the detection of IgG antibody to Rift Valley fever virus in humans.
Next Document:  Paroxysmal atrioventricular block and right coronary artery stenosis without acute myocardial infarc...