Amino Acid Sequence|Animals|Arginine|Cell Membrane|Computational Biology|Computer Simulation|Conserved Sequence|Glutamic Acid|Humans|Hydrogen Bonding|Ion Channel Gating|Ligands|Models, Molecular|Molecular Sequence Data|Protein Structure, Quaternary|Protein Structure, Tertiary|Receptors, Nicotinic|Sequence Alignment|Structural Homology, Protein|Water