UC San Diego

The Anoctamin Family of proteins is closely related to both Transmembrane Channel-like proteins and DUF221 proteins who's functions are largely unknown. These three families are grouped into a larger superfamily called the Anoctamin Superfamily. Here, we have analyzed the topologies of each of these three families of proteins using Bioinformatic programs included in the BioV Suite: AveHAS, GSAT, CLUSTAL X, and SuperTree. We have constructed structural schemes for each of these families and deduced a possible function for the DUF221 Family. We suggest members are involved in NaCl tolerance. We have also found several families of proteins in the CPA, VIC, and TRP superfamilies that are evolutionarily linked to the Anoctamin Superfamily. Identification of these homologous families is important because it provides insight into possible mechanisms for the poorly characterized proteins in the Anoctamin Superfamily. The results establish for the first time that the Anoctamin Superfamily is a sub-superfamily of the largest known superfamily of transmembrane channel proteins, the Voltage -gated Ion Channel (VIC) Superfamiy