Functions as a dominant-negative VHL to serve as a protector of HIFalpha. Interacts via the beta domain with the ODD domain of HIF1A. This interaction is independent of prolyl hydroxylation of HIF1A. Abundantly expressed in the placenta. Has little or no E3 ubiquitin ligase activity as it lacks the alpha domain required for nucleating the multiprotein E3 ubiquitin ligase complex. Belongs to the VHL family.