Protein sequence alignment of BKγ subunits in humans. The corresponding amino acid sequences for different domains or segments are assigned and used for the generation of chimeric proteins. Cluster (++) refers to the cluster of positively charged amino acids. The key residues of the consensus sequence (LxxLxLxxN) in each LRR unit are marked by black squares below. Four cysteine pairs for potential disulfide formation are indicated. The two residues in γ3 used for point mutation analyses, D269 and K304, are outlined in blue.