Publication Date:
1999-02-12
Description:
An alanyl-alanyl-phenylalanyl-7-amino-4-methylcoumarin-hydrolyzing protease particle copurifying with 26S proteasomes was isolated and identified as tripeptidyl peptidase II (TPPII), a cytosolic subtilisin-like peptidase of unknown function. The particle is larger than the 26S proteasome and has a rod-shaped, dynamic supramolecular structure. TPPII exhibits enhanced activity in proteasome inhibitor-adapted cells and degrades polypeptides by exo- as well as predominantly trypsin-like endoproteolytic cleavage. TPPII may thus participate in extralysosomal polypeptide degradation and may in part account for nonproteasomal epitope generation as postulated for certain major histocompatibility complex class I alleles. In addition, TPPII may be able to substitute for some metabolic functions of the proteasome.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Geier, E -- Pfeifer, G -- Wilm, M -- Lucchiari-Hartz, M -- Baumeister, W -- Eichmann, K -- Niedermann, G -- New York, N.Y. -- Science. 1999 Feb 12;283(5404):978-81.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max-Planck Institute of Immunobiology, Stubeweg 51, D-79108 Freiburg, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/9974389" target="_blank"〉PubMed〈/a〉
Keywords:
Acetylcysteine/analogs & derivatives/pharmacology
;
Alleles
;
Amino Acid Chloromethyl Ketones/pharmacology
;
Aminopeptidases
;
Animals
;
Cell Survival
;
Coumarins/metabolism
;
Cysteine Endopeptidases/*metabolism
;
Cytosol/enzymology
;
Dipeptidyl-Peptidases and Tripeptidyl-Peptidases
;
Epitopes/metabolism
;
Genes, MHC Class I
;
Hydrolysis
;
Mice
;
Molecular Weight
;
Multienzyme Complexes/*metabolism
;
Oligopeptides/metabolism
;
Proteasome Endopeptidase Complex
;
Serine Endopeptidases/chemistry/isolation & purification/*metabolism
;
Serine Proteinase Inhibitors/pharmacology
;
Substrate Specificity
;
Tumor Cells, Cultured
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
