title: Homotypic interaction and amino acid distribution of unilaterally conserved transmembrane helices.
abstract: Formation of non-covalent functional complexes of integral membrane proteins is frequently supported by sequence-specific interaction of their transmembrane helices. Here, we aligned human single-span membrane proteins with orthologs from other eukaryotes. We find that almost half of the human single-span membrane proteins contain a transmembrane helix that exhibits significant non-random unilateral conservation. Furthermore, unilateral conservation of transmembrane domains (TMDs) correlates well with their ability to self-interact. Glycine, polar non-ionizable, and aromatic amino acids are overrepresented in conserved versus non-conserved helix faces. Hence, our genome-wide analysis indicates that these amino acid types generally support interaction of single-span membrane protein TMDs.
authors.affiliation: Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3,85354 Freising, Germany.
authors.forename: Christian Lothar
authors.initials: CL
authors.lastname: Ried
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kube
authors.forename: Jan
authors.initials: J
authors.lastname: Kirrbach
authors.forename: Dieter
authors.initials: D
authors.lastname: Langosch
mesh_terms: D000596:Amino Acids / Q000032:analysis; D005998:Glycine / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D055503:Protein Multimerization; D017386:Sequence Homology, Amino Acid
chemical_list: D000596:Amino Acids; D008565:Membrane Proteins; D005998:Glycine