Differential activation of signal transducer and activator of transcription (STAT)-3 and STAT-1 transcription factors and c-fos messenger ribonucleic acid by interleukin-6 and interferon-gamma in Sertoli cells
Jenab,Shirzad; Morris,Patricia L.
Endocrinology 137(11): 4738-4743
Publication date: 1996
The regulation of expression of the immediate early gene c-fos messengerRNA (mRNA) by interleukin-6 (IL-6) and interferon-gamma (IFN gamma) wasinvestigated using primary Sertoli cells established from immature rattestis. Using electrophoretic mobility shift assay, we show that IL-6 andIFN gamma predominantly activate signal transducers and activators oftranscription-3 and -1 proteins after 15 min of treatment, respectively,whereas solution hybridization and Northern blot analyses show adifferential induction of the c-fos mRNA by the two cytokines. IL-6stimulated c-fos mRNA levels by 6-fold after 45 min; these levels returnedto control values by 12 h of treatment. In contrast, IFN gamma increasedc-fos message 2-fold transiently, with RNA at the control level by 2 hafter treatment. These cytokine- dependent inductions of c-fos mRNA levelswere not affected by cyclohexamide, but were diminished by actinomycin Dpretreatments, consistent with regulation at the transcriptional level. Thedifferential activation of this testicular c-fos gene thus suggestsmultiple mechanisms and/or pathways of cytokine regulation in Sertolicells.