Figure 1.

Sequence evaluation of SK2. A, Alignment of the amino acid sequences from the cloned SK2 channel from Apteronotus (Apt) with the human channel (hSK2). Sequence variations are highlighted. The six predicted transmembrane segments (S1–S6) are indicated (black lines) along with the channel pore and predicted CaMBD (calmodulin-binding domain) (gray lines). B, Phylogenic comparison of the AptSK2 channel with the human (h), rat (r), mouse (m) SK channels and the human BK channel shows that the AptSK2 channel is homologous to the previously cloned mammalian channels. Analysis was with the Clustal W method within the Lasergene software package.