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Updated: May 20, 2026

Identification and Classification of Position-specific GABAA Receptor Subunit Missense Variants for Their Role In Hippocampal Pyramidal Neurons
Published on: June 6, 2025
Impact of helix irregularities on sequence alignment and homology modeling of G protein-coupled receptors
Angel Gonzalez1, Arnau Cordomí, Gianluigi Caltabiano
1Laboratori de Medicina Computacional, Unitat de Bioestadística, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
Abstract:
Comparison of the crystal structures of G protein-coupled receptors (GPCRs) revealed backbone irregularities in the majority of the transmembrane (TM) helices. Among these, wide (π bulge) and tight (3(10)) helical turns on TM2 and TM5 deserve special attention because of their proximity to the ligand binding site. These irregularities are related to residue insertion or deletion (reflected by inclusion of gaps in sequence alignments) accumulated during the evolution of these two helices. These findings have direct implications for the sequence alignments, phylogeny reconstruction, and homology modeling of class A GPCRs.
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