HTLV-1 p27rex stabilizes human interleukin-2 receptor alpha chain mRNA.
Expression of the pX gene products (p40tax, p27rex and p21X-III) of human T cell leukemia virus type 1 (HTLV-1), which is known to be a causative agent of adult T cell lymphoma/leukemia, induces expression of the interleukin-2 receptor alpha chain (IL-2R alpha) on infected T cells. Comparison of IL-2R alpha promoter activities has revealed that the transcriptional activation of the promoter alone cannot explain the large numbers of IL-2R alpha expressed on HTLV-1 infected cells. We found that the rates of the IL-2R alpha mRNA degradation were greatly reduced in pX-positive cells as compared with pX-negative cells. Simultaneous transfection of the expression vector plasmid containing IL-2R alpha cDNA and similar plasmids containing various pX sequences showed that p27rex elongated the half life of IL-2R alpha mRNA. As p27rex did not affect the transport of the IL-2R alpha mRNA from nucleus to cytoplasm, prolongation of the IL-2R alpha mRNA half life by p27rex is ascribed to stabilization of the mRNA. Experiments using deletion mutants and chimeric constructs of the IL-2R alpha cDNA demonstrated that the coding sequence but not the 5' or 3' untranslated region of the IL-2R alpha mRNA sequence is responsible for its protection by p27rex.
Kanamori
H
H
Department of Medical Chemistry, Kyoto University Faculty of Medicine, Japan.
Suzuki
N
N
Siomi
H
H
Nosaka
T
T
Sato
A
A
Sabe
H
H
Hatanaka
M
M
Honjo
T
T
D002460:Cell Line; D015967:Gene Expression Regulation, Viral; D016370:Gene Products, rex / Q000378:metabolism*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D046911:Macromolecular Substances; D010957:Plasmids; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D015375:Receptors, Interleukin-2 / Q000235:genetics*; D015183:Restriction Mapping; D013601:T-Lymphocytes / Q000276:immunology
D016370:Gene Products, rex; D046911:Macromolecular Substances; D012333:RNA, Messenger; D015375:Receptors, Interleukin-2