Abstract
Interleukin 9 (IL-9) is a cytokine preferentially produced by T helper type 2 lymphocytes and active on various cell types such as T- and B-lymphocytes, mast cells and haemopoietic progenitors. The IL-9 receptor (IL-9R) belongs to the haemopoietic receptor superfamily and its signal transduction involves mainly the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. Here we studied the implication of a novel family of suppressors of cytokine signalling (called CIS, for cytokine-inducible SH2-containing protein, and SOCS, for suppressor of cytokine signalling) in IL-9 signal attenuation. In BW5147 T-cell lymphoma, IL-9 induced the rapid expression of CIS, SOCS-2 and SOCS-3 with a peak after 2 h of stimulation. Using IL-9R mutants, we showed that STAT activation is required for CIS/SOCS induction: CIS and SOCS-2 expression was induced either via STAT1 and/or STAT3 or via STAT5 but only STAT1 and/or STAT3 were involved in SOCS-3 expression. The effect of these three proteins on IL-9 signal transduction was assessed by transient transfection in HEK-293 cells expressing the components of the IL-9 signalling pathway and a STAT-responsive reporter construct. These experiments showed that only SOCS-3 is able to inhibit IL-9-induced signal transduction; neither CIS nor SOCS-2 exerted any effect. Stable transfection of CIS and SOCS-3 in BW5147 lymphoma cells showed that only overexpression of SOCS-3 had an inhibitory activity on STAT activation, gene induction and the anti-apoptotic activity of IL-9. By contrast, CIS failed to affect the IL-9 response.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Blotting, Western
-
Cell Line
-
DNA-Binding Proteins / antagonists & inhibitors
-
DNA-Binding Proteins / metabolism
-
Feedback / drug effects
-
Humans
-
Immediate-Early Proteins / genetics
-
Immediate-Early Proteins / metabolism*
-
Interleukin-9 / antagonists & inhibitors*
-
Interleukin-9 / pharmacology*
-
Janus Kinase 1
-
Milk Proteins*
-
Mutation
-
Protein-Tyrosine Kinases / metabolism
-
Proteins / genetics
-
Proteins / metabolism*
-
RNA, Messenger / genetics
-
RNA, Messenger / metabolism
-
Receptors, Interleukin / antagonists & inhibitors
-
Receptors, Interleukin / genetics
-
Receptors, Interleukin / metabolism
-
Receptors, Interleukin-9
-
Repressor Proteins*
-
STAT1 Transcription Factor
-
STAT3 Transcription Factor
-
STAT5 Transcription Factor
-
Signal Transduction / drug effects*
-
Suppressor of Cytokine Signaling 3 Protein
-
Suppressor of Cytokine Signaling Proteins
-
Trans-Activators / antagonists & inhibitors
-
Trans-Activators / metabolism
-
Transcription Factors*
-
Transfection
-
Tumor Cells, Cultured
Substances
-
DNA-Binding Proteins
-
IL9R protein, human
-
Immediate-Early Proteins
-
Interleukin-9
-
Milk Proteins
-
Proteins
-
RNA, Messenger
-
Receptors, Interleukin
-
Receptors, Interleukin-9
-
Repressor Proteins
-
SOCS2 protein, human
-
SOCS3 protein, human
-
STAT1 Transcription Factor
-
STAT1 protein, human
-
STAT3 Transcription Factor
-
STAT3 protein, human
-
STAT5 Transcription Factor
-
Suppressor of Cytokine Signaling 3 Protein
-
Suppressor of Cytokine Signaling Proteins
-
Trans-Activators
-
Transcription Factors
-
cytokine inducible SH2-containing protein
-
Protein-Tyrosine Kinases
-
JAK1 protein, human
-
Janus Kinase 1