Intra-nuclear mobility and target search mechanisms of transcription factors: A single-molecule perspective on gene expression

► Transcription of specific genes has fundamental importance in all cellular processes. ► DNA-binding transcription factors are key players in transcription regulation. ► Target search and DNA-binding dictate transcription factor regulation kinetics. ► Intra-nuclear mobility and target search are still elusive and puzzling. ► Direct observation of transcription factors might clarify regulation mechanisms.