Figure 7. Illustration describing the transcriptional regulation of HIF-target genes in cells either expressing or lacking Rb.

(A) In cells that are Rb-positive, the full transcriptional activation capacity of the HIF1-TRIP230 complex is repressed or muted resulting in regulated expression of HIF1 target genes. (B) In cells lacking Rb, gene expression mediated by HIF1 becomes uncontrolled.