PMID- 10567354
OWN - NLM
STAT- MEDLINE
DCOM- 19991229
LR  - 20190508
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 48
DP  - 1999 Nov 26
TI  - Structural and functional characterizations of the proteasome-activating protein 
      PA26 from Trypanosoma brucei.
PG  - 33921-30
AB  - The activated 20 S proteasome, which has been found only in mammalian cells, is
      composed of two heptamer rings of an activator protein on each end of the 20 S
      proteasome and is inducible by interferon-gamma. A 20 S proteasome has been
      recently identified in a protozoan pathogen Trypanosoma brucei, but there has
      been no experimental evidence yet for the presence of a 26 S proteasome. Instead,
      an activated form of 20 S proteasome was isolated from this organism, which has
      significantly enhanced peptidase activities. It consists of an additional
      activator protein with an estimated molecular mass of 26 kDa (PA26) (To, W. Y.,
      and Wang, C. C. (1997) FEBS Lett. 404, 253-262). The profile and sequences of
      tryptic peptides from PA26 were determined by mass spectrometry; no matches were 
      found in the data base. The peptide sequences were used in reverse
      transcriptase-polymerase chain reaction to isolate a full-length cDNA clone
      encoding PA26. The protein sequence thus derived from it indicates little
      sequence identity with those of mammalian activator proteins PA28 alpha, beta, or
      gamma. There is only a single copy of PA26 gene in T. brucei. Purified
      recombinant PA26 polymerizes spontaneously to form heptamer ring with an outer
      diameter of 8.5 nm. The ring binds and activates 20 S proteasomes from T. brucei 
      as well as rat, whereas human PA28alpha can neither bind nor activate T. brucei
      20 S proteasome. The former is thus apparently more ubiquitous than PA28 in its
      capability of binding to and activating 20 S proteasomes. Its presence in T.
      brucei may also suggest a more ancient origin of proteasome activator proteins
      and a much wider involvement in protein degradation among other eukaryotic
      organisms than was originally envisaged.
FAU - Yao, Y
AU  - Yao Y
AD  - Department of Pharmaceutical Chemistry, Howard Hughes Medical Institute,
      University of California, San Francisco, California 94143, USA.
FAU - Huang, L
AU  - Huang L
FAU - Krutchinsky, A
AU  - Krutchinsky A
FAU - Wong, M L
AU  - Wong ML
FAU - Standing, K G
AU  - Standing KG
FAU - Burlingame, A L
AU  - Burlingame AL
FAU - Wang, C C
AU  - Wang CC
LA  - eng
SI  - GENBANK/AF085602
GR  - R01 AI-21786/AI/NIAID NIH HHS/United States
GR  - R01 RR-01614/RR/NCRR NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (DNA, Complementary)
RN  - 0 (DNA, Protozoan)
RN  - 0 (Insect Proteins)
RN  - 0 (Multienzyme Complexes)
RN  - 0 (PA26 protein, Trypanosoma brucei)
RN  - 0 (Protein Isoforms)
RN  - 0 (Protozoan Proteins)
RN  - 0 (Recombinant Fusion Proteins)
RN  - 4QD397987E (Histidine)
RN  - EC 3.4.22.- (Cysteine Endopeptidases)
RN  - EC 3.4.25.1 (Proteasome Endopeptidase Complex)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Blotting, Southern
MH  - Cloning, Molecular
MH  - Cysteine Endopeptidases/chemistry/genetics/*metabolism
MH  - DNA, Complementary/chemistry/genetics
MH  - DNA, Protozoan/analysis/genetics
MH  - Electrophoresis, Gel, Two-Dimensional
MH  - Electrophoresis, Polyacrylamide Gel
MH  - Enzyme Activation
MH  - Gene Dosage
MH  - Histidine/genetics
MH  - Immunoblotting
MH  - Insect Proteins/chemistry/genetics/*metabolism
MH  - Mass Spectrometry/methods
MH  - Molecular Sequence Data
MH  - Multienzyme Complexes/chemistry/genetics/*metabolism
MH  - Proteasome Endopeptidase Complex
MH  - Protein Conformation
MH  - Protein Isoforms/genetics
MH  - *Protozoan Proteins
MH  - Rats
MH  - Recombinant Fusion Proteins/chemistry/genetics/ultrastructure
MH  - Sequence Alignment
MH  - Sequence Analysis, DNA
MH  - Sequence Analysis, Protein
MH  - Sequence Homology, Amino Acid
MH  - Trypanosoma brucei brucei/chemistry/enzymology/*genetics
EDAT- 1999/11/24 00:00
MHDA- 1999/11/24 00:01
CRDT- 1999/11/24 00:00
PHST- 1999/11/24 00:00 [pubmed]
PHST- 1999/11/24 00:01 [medline]
PHST- 1999/11/24 00:00 [entrez]
AID - 10.1074/jbc.274.48.33921 [doi]
PST - ppublish
SO  - J Biol Chem. 1999 Nov 26;274(48):33921-30. doi: 10.1074/jbc.274.48.33921.