Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.4.99.6 (
sialyltransferase
)
1,546
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Proprotein Convertase 7 (PC7) is a Furin-like
endoprotease
that cleaves precursor proteins at basic amino acids. PC7 is concentrated in the trans-Golgi network (TGN) but it shuttles between the plasma membrane and the TGN depending on sequences in the cytoplasmic tail. A short region containing a three amino acids motif, P
724
-L
725
-C
726
, is essential and sufficient for internalization of PC7 but not for TGN localization, which requires the additional presence of the juxtamembrane region. In this study we have investigated the contribution of a cluster of basic amino acids and two reversibly palmitoylated cysteine residues to endocytic trafficking. Stable cell lines overexpressing chimeric proteins (CD25 and CD46) containing the cytoplasmic domain of PC7 in which the basic cluster alone or together with both palmitoylated cysteines are mutated showed enhanced surface expression as demonstrated by immunofluorescence experiments and surface biotinylation. The mutant proteins no longer recycled to the TGN in antibody uptake experiments and accumulated in an endosomal compartment. Recycling of wild type PC7 to the TGN is blocked by nocodazole, suggesting that PC7 shuttles to the TGN via late endosomes, similar to Furin. Unlike furin, however, PC7 was found to recycle to a region within the TGN, which is deficient in
sialyltransferase
, as shown by resialylation experiments. In conclusion, a novel motif, composed of a basic amino acid cluster and two palmitoylated cysteines are essential for TGN localization and endocytic trafficking.
...
PMID:Endosome to trans-Golgi network transport of Proprotein Convertase 7 is mediated by a cluster of basic amino acids and palmitoylated cysteines. 2841 20
