The 90K protein increases major histocompatibility complex class I expression and is regulated by hormones, gamma-interferon, and double-strand polynucleotides.
Here we report the cloning of the rat 90K, a homolog of the mouse cyclophilin C-associated protein/mouse adherent macrophage and human 90K. The protein is constitutively expressed by FRTL-5 thyrocytes, and its levels are modulated by TSH, insulin/IGF-I, and gamma-interferon. Transfection of the cells with 90K cDNA or exposure to purified 90K resulted in a significant increase of the expression of major histocompatibility complex class I but not class II antigens. An increased expression of 90K was obtained after viral infection or introduction into the cells of fragments of viral, bacterial, or mammalian double-strand polynucleotides. The increase was sequence independent, not CpG mediated, and associated with the expression of molecules characterizing antigen-presenting-cell phenotype. The present data along with results from previous studies suggest that 90K plays an important role in the maintenance of an appropriate level of immune response.
Grassadonia
Antonino
A
Cell Regulation Section, Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Tinari
Nicola
N
Fiorentino
Bruno
B
Suzuki
Koichi
K
Nakazato
Minoru
M
De Tursi
Michele
M
Giuliani
Cesidio
C
Napolitano
Giorgio
G
Singer
Dinah S
DS
Iacobelli
Stefano
S
Kohn
Leonard D
LD
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000494:pharmacology*; D016326:Extracellular Matrix Proteins; D006561:Herpes Simplex / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006728:Hormones / Q000494:pharmacology*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D008969:Molecular Sequence Data; D011119:Polynucleotides / Q000235:genetics / Q000494:pharmacology*; D011506:Proteins / Q000235:genetics / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017386:Sequence Homology, Amino Acid
D002352:Carrier Proteins; D016326:Extracellular Matrix Proteins; D015395:Histocompatibility Antigens Class I; D006728:Hormones; C492608:Lgals3bp protein, rat; D011119:Polynucleotides; D011506:Proteins; D012333:RNA, Messenger; D007371:Interferon-gamma; D004247:DNA