Structure-Based Sequence Alignment of the Transmembrane Domains of All Human GPCRs: Phylogenetic, Structural and Functional Implications
Fig 2
Conserved inter-helical contacts.
Top left: Diagram of 40 conserved inter-helical contacts (CHICOs) present in at least 23 out of 24 studied class A structures. The contacts common to all classes are shown in purple, and contacts present only in class A in orange. Top right: List of these contacts in Ballesteros-Weinstein numbering scheme. Bottom: Extracellular view of the same contacts in the β2 crystal structure. The contacts in the inner and outer half of the membrane are shows on the left and right respectively.