plosone-phylo
Figure 2
Gene tree of L-type calcium channels illustrating the evolution of calmodulin binding, amino terminal (NSCaTE) and carboxyl terminal (Pre-IQ/IQ) motifs in L-type Cav1 channels.All animal phyla including single cell protozoans (such as Paramecium) and simple multicellular organisms (placozoans, sponge) have an IQ motif. A N-terminal NSCaTE (xWxxx(IorL)xxxx) motif evolved in common invertebrate ancestors (coelomates) and retained in all major phylogenetic groups. While the Pre-IQ and IQ motifs are featured in all L-type channels of metazoans, the NSCaTE motif is missing in some Arthropod species, including many insects, suggesting that NSCaTE is not an essential feature of L-type channels. NSCaTE was lost in Cav1.1 and Cav1.4 after the speciation of L-type channels to four gene isoforms in vertebrates. Almost every NSCaTE containing L-type channel has a downstream methionine (Met2) from the start codon (Met1) which could serve as an alternative translational start site for inclusion (Met1) or exclusion (Met2) of NSCaTE in L-type channels.
Figure 2
Gene tree of L-type calcium channels illustrating the evolution of calmodulin binding, amino terminal (NSCaTE) and carboxyl terminal (Pre-IQ/IQ) motifs in L-type Cav1 channels.All animal phyla including single cell protozoans (such as Paramecium) and simple multicellular organisms (placozoans, sponge) have an IQ motif. A N-terminal NSCaTE (xWxxx(IorL)xxxx) motif evolved in common invertebrate ancestors (coelomates) and retained in all major phylogenetic groups. While the Pre-IQ and IQ motifs are featured in all L-type channels of metazoans, the NSCaTE motif is missing in some Arthropod species, including many insects, suggesting that NSCaTE is not an essential feature of L-type channels. NSCaTE was lost in Cav1.1 and Cav1.4 after the speciation of L-type channels to four gene isoforms in vertebrates. Almost every NSCaTE containing L-type channel has a downstream methionine (Met2) from the start codon (Met1) which could serve as an alternative translational start site for inclusion (Met1) or exclusion (Met2) of NSCaTE in L-type channels.