Tissue distribution of constitutive proteasomes, immunoproteasomes, and PA28 in rats.
We investigated the expression of standard proteasomes, immunoproteasomes, and their regulators, PA28, and PA700, in rat tissues. Immunoproteasomes (with subunits LMP2, LMP7, and MECL1) were abundant in the spleen but almost absent in the brain. In contrast, standard proteasomes (with X, Y, and Z) were highly expressed in the brain but not in the spleen. Both proteasome types were present in the lung and the liver. PA700 subunits (p112, S5a, and p45) were found in all tissues. PA28alpha, PA28beta, and PA28gamma were also expressed in all tissues, except for the brain which contained very little PA28beta. The results did not depend on rat sex or age. The cleavage specificity for peptide substrates differed greatly between brain and spleen proteasomes. Hybrid proteasomes, containing both PA28alphabeta and PA700, were not present in the brain but in all other tissues examined.
Noda
C
C
Hyogo College, Kakogawa, Hyogo, 675-0101, Japan. cnoda@humans-kc.hyogo-dai.ac.jp
Tanahashi
N
N
Shimbara
N
N
Hendil
K B
KB
Tanaka
K
K
D000367:Age Factors; D000818:Animals; D001921:Brain / Q000378:metabolism; D018797:Cell Cycle Proteins; D003546:Cysteine Endopeptidases / Q000096:biosynthesis* / Q000276:immunology* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D007074:Immunoglobulin G / Q000378:metabolism; D007371:Interferon-gamma / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D008297:Male; D009097:Multienzyme Complexes / Q000096:biosynthesis* / Q000276:immunology* / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism; D011233:Precipitin Tests; D046988:Proteasome Endopeptidase Complex; D011485:Protein Binding; D014176:Protein Biosynthesis; D011506:Proteins; D051381:Rats; D017208:Rats, Wistar; D012737:Sex Factors; D013154:Spleen / Q000378:metabolism; D014018:Tissue Distribution; D014763:Viral Matrix Proteins / Q000096:biosynthesis
D018797:Cell Cycle Proteins; C037662:EBV-associated membrane antigen, Epstein-Barr virus; D007074:Immunoglobulin G; D009097:Multienzyme Complexes; C085834:PA700 proteasome activator; D011506:Proteins; C490050:Psme1 protein, rat; C490052:Psme2 protein, rat; D014763:Viral Matrix Proteins; D007371:Interferon-gamma; D010447:Peptide Hydrolases; D003546:Cysteine Endopeptidases; C077436:LMP7 protein; D046988:Proteasome Endopeptidase Complex; C490921:Psmb10 protein, rat