Figure 2.

 Domain structure of HIF-1α and interacting factors. Domains: NLS, nuclear localisation signal; bHLH, basic helix-loop-helix (DNA binding and dimerisation); PAS, Per/Ahr-ARNT/Sim (dimerisation); PAC, PAS associated C-terminal domain; NTAD, N-terminal transactivation domain (transcriptional transactivation); CTAD, C-terminal transactivation domain (transcriptional transactivation); Factors: PHD, HIF prolyl hydroxylase; ARD1, ADP-ribosylation factor domain; FIH, factor inhibiting HIF; pVHL, von Hippel-Lindau tumour suppressor protein.