Structural basis of latrophilin-FLRT interaction.
Latrophilins, receptors for spider venom α-latrotoxin, are adhesion type G-protein-coupled receptors with emerging functions in synapse development. The N-terminal region binds the endogenous cell adhesion molecule FLRT, a major regulator of cortical and synapse development. We present crystallographic data for the mouse Latrophilin3 lectin and olfactomedin-like (Olf) domains, thereby revealing the Olf β-propeller fold and conserved calcium-binding site. We locate the FLRT-Latrophilin binding surfaces by a combination of sequence conservation analysis, point mutagenesis, and surface plasmon resonance experiments. In stripe assays, we show that wild-type Latrophilin3 and its high-affinity interactor FLRT2, but not the binding-impaired mutants we generated, promote HeLa cell adhesion. In contrast, cortical neurons expressing endogenous FLRTs are repelled by wild-type Latrophilin3 and not by the binding-impaired mutant. Taken together, we present molecular level insights into Latrophilin structure, its FLRT-binding mechanism, and a role for Latrophilin and FLRT that goes beyond a simply adhesive interaction.
Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, UK.
Verity A
VA
Jackson
Max-Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Munich-Martinsried, Germany.
Daniel
D
del Toro
Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, UK.
Maria
M
Carrasquero
Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, UK.
Pietro
P
Roversi
Division of Structural Biology, Oxford University, Roosevelt Drive, Oxford OX3 7BN, UK.
Karl
K
Harlos
Max-Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Munich-Martinsried, Germany; Munich Cluster for Systems Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377 Munich, Germany.
Rüdiger
R
Klein
Department of Biochemistry, Oxford University, South Parks Road, Oxford OX1 3QU, UK. Electronic address: elena.seiradake@bioch.ox.ac.uk.
Elena
E
Seiradake
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D011485:Protein Binding; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry* / Q000378:metabolism; D018000:Receptors, Peptide / Q000737:chemistry* / Q000378:metabolism
D008562:Membrane Glycoproteins; D043562:Receptors, G-Protein-Coupled; D018000:Receptors, Peptide; C514259:FLRT2 protein, mouse; C000592543:Adgrl3 protein, mouse