A Mechanism of Transcriptional Regulation of the CSF‐1 Gene by Interferon‐Gamma

Abstract

Interferon (IFN)‐gamma exerts multiple functions including antiviral, anti‐proliferative and immunomodulatory activities, which are mediated through the JAK‐STAT pathway. We observed that IFN‐gamma significantly increases the production of colony stimulating factor‐1 (CSF‐1) by a human lung carcinoma cell line, A549. To gain insight into this mechanism, we determined the unknown nucleotide sequences of 5′‐flanking region of human CSF‐1 gene. About 60 bases upstream of the transcription start site of the CSF‐1 gene contains a possible gamma interferon activated site (GAS), TTCCCATAA. The promoter assay and the electrophoretic mobility gel shift assay revealed that IFN‐gamma stimulates transcription of the CSF‐1 gene through this sequence, which binds STAT1.

• Interferon‐gamma
• CSF‐1
• Cis‐acting element
• GAS
• STAT1