Fig. 5.

Animal models of NPC. The NPC1 protein is highly evolutionarily conserved among eukaryotes. Many model systems of NPC, both spontaneously derived and engineered, are available. We have listed the range of organisms in which NPC-related phenotypes have been reported (see in-text references under ‘Beyond the mouse: additional models of NPC’) and have ranked them in the order of NPC1 protein homology. Some of the current and potential uses of these model organisms for research are also listed. The phylogenetic tree was drawn using Phylogeny.fr (Dereeper et al., 2008) and the mammalian Patched protein, PTCH1, a related RND permease superfamily member and sterol-sensing-domain-containing protein (Hausmann et al., 2009), was used as an outgroup. For C. elegans, the NCR1 protein sequence was used. We apologize if we have failed to mention any additional organisms that have been or are currently being studied in the context of NPC.