Transcription factor complexed with DNA. Molecular model showing the transcriptional factor c-fos/c-jun (yellow and pink) bound to a strand of DNA (deoxyribonucleic acid, orange and blue). Transcription factors are proteins that bind to specific sequences of DNA and control the transcription (transfer) of genetic information from DNA to RNA (ribonucleic acid). The c-fos/c-jun transcription factor regulates gene expression in response to stress stimuli and infection.