Critical Cytoplasmic Domains of Human Interleukin-9 Receptor α Chain in Interleukin-9-mediated Cell Proliferation and Signal Transduction

Autor: Yu Chung Yang, Jon McMahel, Yuan Xiao Zhu, Tinggui Yin, Hui Bin Sun, Monica Lik Shing Tsang, Susan Grigsby
Rok vydání: 1997
Předmět:
STAT3 Transcription Factor
Cytoplasm
Proto-Oncogene Proteins c-jun
T-Lymphocytes
Genes
myc

Transfection
Biochemistry
Receptor tyrosine kinase
Mice
Structure-Activity Relationship
chemistry.chemical_compound
Cell surface receptor
Animals
Humans
Point Mutation
Phosphotyrosine
Molecular Biology
Cells
Cultured

Sequence Deletion
Receptors
Interleukin-9

biology
Cell growth
Interleukin-9
Intracellular Signaling Peptides and Proteins
Janus Kinase 3
JAK-STAT signaling pathway
Tyrosine phosphorylation
Janus Kinase 1
Receptors
Interleukin

Cell Biology
Protein-Tyrosine Kinases
Phosphoproteins
Molecular biology
Recombinant Proteins
DNA-Binding Proteins
chemistry
Insulin Receptor Substrate Proteins
Trans-Activators
biology.protein
STAT protein
Signal transduction
Janus kinase
Cell Division
Signal Transduction
Zdroj: Journal of Biological Chemistry. 272:21334-21340
ISSN: 0021-9258
DOI: 10.1074/jbc.272.34.21334
Popis: Interleukin-9 receptor (IL-9R) complex consists of a ligand-specific alpha chain and IL-2R gamma chain. In this study, two regions in the cytoplasmic domain of human IL-9Ralpha were found to be important for IL-9-mediated cell growth. A membrane-proximal region that contains the BOX1 consensus sequence is required for IL-9-induced cell proliferation and tyrosine phosphorylation of Janus kinases (JAKs). Deletion of this region or internal deletion of the BOX1 motif abrogated IL-9-induced cell proliferation and signal transduction. However, substitution of the Pro-X-Pro in the BOX1 motif with Ala-X-Ala failed to abolish IL-9-induced cell proliferation but decreased IL-9-mediated tyrosine phosphorylation of JAK kinases, insulin receptor substrate-2, and signal transducer and activator of transcription 3 (STAT3) and expression of c-myc and junB. Another important region is downstream of the BOX1 motif and contains a STAT3 binding motif YLPQ. Deletion of this region significantly impaired IL-9-induced cell growth, activation of JAK kinases, insulin receptor substrate-2, and STAT3 and expression of early response genes. A point mutation changing YLPQ into YLPA greatly reduced IL-9-induced activation of STAT3 and expression of c-myc but did not affect cell proliferation. These results suggest that cooperation or cross-talk of signaling molecules associated with different domains of IL-9Ralpha other than STAT3 is essential for IL-9-mediated cell growth.
Databáze: OpenAIRE