Figure 3.

The 7SK snRNP complex is present at the promoters of most Pol II transcribed genes. The 7SK snRNP is recruited onto promoter-proximal regions through KAP1. Here, the P-TEFb kinase is directly released from the 7SK snRNP complex (by the mechanisms described in Fig. 2) and ‘on-site' activation (Pol II, DSIF, and NELF phosphorylation) occurs at the targeted gene. It remains unclear what the fate of KAP1 and the core 7SK snRNP is once P-TEFb has been released from the promoter-proximal region. TF, transcription factor.