Interaction and functional interference of glucocorticoid receptor and SOCS1.
Cytokine and glucocorticoid (GC) hormone signaling act in an integrated fashion to control inflammation and immune response. Here we establish a new mode of interaction of these two pathways and propose Suppressor of Cytokine Signaling (SOCS)-1 as an essential player in mediating cross-talk. We observed that glucocorticoid receptor (GR) and SOCS1 form an intracellular complex through an interaction, which required the SH2 domain of SOCS1 and the ligand binding domain of GR. Furthermore, GC stimulation was found to increase the nuclear level of SOCS1. SOCS1 binding to the GR did not require ligand binding of the receptor; however, it was abolished after long term GC stimulation, suggesting a functional role of the interaction for the early phase of GC action. The interaction between GR and SOCS1 appeared to negatively influence the transcription of the two GR-regulated genes, FKBP5 and MKP1, because the GC-dependent expression of these genes was inhibited by the SOCS1 inducer IFNgamma and enhanced in SOCS1-deficient murine embryonic fibroblasts as compared with IFNgamma treated wild-type cells. Our results suggest a prominent role of SOCS1 in the early phase of cross-talk between GR and cytokine signaling.
Division of Medical Biochemistry, Biocenter, Innsbruck Medical University, Fritz-Pregl-Strasse 3, A-6020 Innsbruck, Austria.
Michael C
MC
Haffner
Andreas
A
Jurgeit
Chiara
C
Berlato
Stephan
S
Geley
Nirmala
N
Parajuli
Akihiko
A
Yoshimura
Wolfgang
W
Doppler
D000818:Animals; D019556:COS Cells; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D002522:Chlorocebus aethiops; D005938:Glucocorticoids / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D041681:NIH 3T3 Cells; D011485:Protein Binding; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000378:metabolism*; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000378:metabolism*; D018909:src Homology Domains
D005938:Glucocorticoids; D011965:Receptors, Glucocorticoid; C491590:Socs1 protein, mouse; D000071222:Suppressor of Cytokine Signaling 1 Protein; D050826:Suppressor of Cytokine Signaling Proteins