Alanine insertions into the glycophorin A transmembrane helix are found to disrupt helix-helix dimerization in a way that is fully consistent with earlier saturation mutagenesis data, suggesting that Ala-insertion scanning can be used to rapidly map the approximate location of structurally and/or functionally important segments in transmembrane helices.
Ala-insertion scanning mutagenesis of the glycophorin A transmembrane helix: a rapid way to map helix-helix interactions in integral membrane proteins.