title: The juxtamembrane regions of human receptor tyrosine kinases exhibit conserved interaction sites with anionic lipids.
abstract: Receptor tyrosine kinases (RTKs) play a critical role in diverse cellular processes and their activity is regulated by lipids in the surrounding membrane, including PIP2 (phosphatidylinositol-4,5-bisphosphate) in the inner leaflet, and GM3 (monosialodihexosylganglioside) in the outer leaflet. However, the precise details of the interactions at the molecular level remain to be fully characterised. Using a multiscale molecular dynamics simulation approach, we comprehensively characterise anionic lipid interactions with all 58 known human RTKs. Our results demonstrate that the juxtamembrane (JM) regions of RTKs are critical for inducing clustering of anionic lipids, including PIP2, both in simple asymmetric bilayers, and in more complex mixed membranes. Clustering is predominantly driven by interactions between a conserved cluster of basic residues within the first five positions of the JM region, and negatively charged lipid headgroups. This highlights a conserved interaction pattern shared across the human RTK family. In particular predominantly the N-terminal residues of the JM region are involved in the interactions with PIP2, whilst residues within the distal JM region exhibit comparatively less lipid specificity. Our results suggest that JM-lipid interactions play a key role in RTK structure and function, and more generally in the nanoscale organisation of receptor-containing cell membranes.
authors.affiliation: Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
authors.forename: George
authors.initials: G
authors.lastname: Hedger
authors.affiliation: Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
authors.forename: Mark S P
authors.initials: MS
authors.lastname: Sansom
authors.affiliation: Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
authors.forename: Heidi
authors.initials: H
authors.lastname: Koldsø
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D016000:Cluster Analysis; D006801:Humans; D008563:Membrane Lipids / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008968:Molecular Conformation; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000737:chemistry / Q000378:metabolism; D056510:Position-Specific Scoring Matrices; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D020794:Receptor Protein-Tyrosine Kinases / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000596:Amino Acids; D008563:Membrane Lipids; D019269:Phosphatidylinositol 4,5-Diphosphate; D020794:Receptor Protein-Tyrosine Kinases