Figure 1.

The gene transcriptional regulatory program. The gene transcriptional regulatory program can be simplified in two levels. At the factor-gene binding level, the "activated" TFs bind to their specific conserved sequence motifs, called transcription factor binding sites (TFBS). When the binding process is completed, the regulation mechanism instructs the gene transcription from transcriptional start site (TSS) (DNA to mRNA); first part of the central dogma in molecular biology.