Induction of protein-tyrosine phosphatase LC-PTP by IL-2 in human T cells. LC-PTP is an early response gene.
Tyrosine phosphorylation has been implicated in interleukin 2 (IL-2)-induced growth signaling and the phosphorylation levels are regulated by the balance of tyrosine kinase and tyrosine phosphatase activities. Here, we demonstrate the rapid activation of a leukocyte tyrosine phosphatase LC-PTP (HePTP) gene expression by IL-2 in an IL-2 dependent human T cell ILT-Mat. Accumulation of LC-PTP mRNA appeared at 1 h and peaked at 6 h after IL-2 stimulation, simultaneous with the G1 to early S phase, and the induction of LC-PTP mRNA did not require protein synthesis. LC-PTP protein increased approximately 6-fold at 8 h after IL-2 stimulation. Nuclear run-on assays showed that the induction of LC-PTP mRNA expression is mostly due to transcriptional activation. These data suggest that LC-PTP is an early response gene and its protein seems to be a crucial molecule which regulates the tyrosine phosphorylation level during T cell proliferation.
Adachi
M
M
Department of Internal Medicine (Section 1), Sapporo Medical University School of Medicine, Japan.
Sekiya
M
M
Ishino
M
M
Sasaki
H
H
Hinoda
Y
Y
Imai
K
K
Yachi
A
A
D004790:Enzyme Induction; D017781:Genes, Immediate-Early; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D017027:Protein Tyrosine Phosphatases / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects / Q000201:enzymology*; D014158:Transcription, Genetic
D007376:Interleukin-2; D012333:RNA, Messenger; D017027:Protein Tyrosine Phosphatases