論文 - 詳細
RRC ID | 39591 |
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著者 | Tsuchida S, Yanagi S, Inatome R, Ding J, Hermann P, Tsujimura T, Matsui N, Yamamura H. |
タイトル | Purification of a 72-kDa protein-tyrosine kinase from rat liver and its identification as Syk: involvement of Syk in signaling events of hepatocytes. |
ジャーナル | J Biochem |
Abstract |
Syk protein-tyrosine kinase (PTK) has been implicated in a variety of hematopoietic cell responses including immunoreceptor signaling. However, so far, there has been no evidence of the expression of Syk or Syk-related PTK in non-hematopoietic tissues. In this study, we have purified from blood cell-depleted rat liver a 72-kDa cytoplasmic PTK which shows cross-reactivity with anti-Syk antibody. Partial amino acid sequence analysis revealed that this 72-kDa PTK is identical to Syk. Immunohistochemical and RT-PCR analyses demonstrated that Syk is expressed in human hepatocytes and two rat liver-derived cell lines, JTC-27 and RLC-16. Furthermore, Syk is significantly tyrosine-phosphorylated in response to angiotensin II in JTC-27 cells, and angiotensin II-induced MAP kinase activation is blocked by the treatment of cells with a Syk-selective inhibitor, piceatannol. These results suggest that Syk plays an important role in signaling events of hepatocytes, such as signaling steps leading to MAP kinase activation by G-protein-coupled receptors. This is the first report of the expression of Syk in non-hematopoietic tissue. |
巻・号 | 127(2) |
ページ | 321-7 |
公開日 | 2000-2-1 |
DOI | 10.1093/oxfordjournals.jbchem.a022610 |
PMID | 10731700 |
MeSH | Amino Acid Sequence Angiotensin II / metabolism Angiotensin II / pharmacology Animals Cells, Cultured Cytosol / enzymology Enzyme Inhibitors / pharmacology Enzyme Precursors / antagonists & inhibitors Enzyme Precursors / immunology Enzyme Precursors / isolation & purification* Enzyme Precursors / metabolism* GTP-Binding Proteins / metabolism Humans Intracellular Signaling Peptides and Proteins Liver / cytology Liver / drug effects Liver / enzymology* Mitogen-Activated Protein Kinases / drug effects Mitogen-Activated Protein Kinases / metabolism Molecular Sequence Data Protein-Tyrosine Kinases / antagonists & inhibitors Protein-Tyrosine Kinases / immunology Protein-Tyrosine Kinases / isolation & purification* Protein-Tyrosine Kinases / metabolism* Rats Signal Transduction* Stilbenes / pharmacology Syk Kinase |
IF | 2.476 |
引用数 | 38 |
WOS 分野 | BIOCHEMISTRY & MOLECULAR BIOLOGY |
リソース情報 | |
ヒト・動物細胞 |