Interaction of acetylcholinesterase with the G4 domain of the laminin α1-chain

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dc.contributor.authorJohnson G.
dc.contributor.authorSwart C.
dc.contributor.authorMoore S.W.
dc.date.accessioned2011-05-15T16:03:23Z
dc.date.available2011-05-15T16:03:23Z
dc.date.issued2008
dc.description.abstractAlthough the primary function of AChE (acetylcholinesterase) is the synaptic hydrolysis of acetylcholine, it appears that the protein is also able to promote various non-cholinergic activities, including cell adhesion, neunte outgrowth and amyloidosis. We have observed previously that AChE is able to bind to mouse laminin-111 in vitro by an electrostatic mechanism. We have also observed that certain mAbs (monoclonal antibodies) recognizing AChE's PAS (peripheral anionic site) inhibit both laminin binding and cell adhesion in neuroblastoma cells. Here, we investigated the interaction sites of the two molecules, using docking, synthetic peptides, ELISAs and conformational interaction site mapping. Mouse AChE was observed on docking to bind to a discontinuous, largely basic, structure, Val2718-Arg-Lys-Arg-Leu 2722, Tyr2738-Tyr2739, Tyr2789-Ile- Lys-Arg-Lys2793 and Val2817-Glu-Arg-Lys2820, on the mouse laminin α1 G4 domain. ELISAs using synthetic peptides confirmed the involvement of the AG-73 site (2719-2729). This site overlaps extensively with laminin's heparin-binding site, and AChE was observed to compete with heparan sulfate for laminin binding. Docking showed the major component of the interaction site on AChE to be the acidic sequence Arg90-Glu-Leu-Ser- Glu-Asp95 on the omega loop, and also the involvement of Pro 40-Pro-Val42, Arg46 (linked to Glu94 by a salt bridge) and the hexapeptide Asp61-Ala-Thr-Thr-Phe-Gln 66. Epitope analysis, using CLiPS™ technology, of seven adhesion-inhibiting mAbs (three anti-human AChE, one anti-Torpedo AChE and three anti-human anti-anti-idiotypic antibodies) showed their major recognition site to be the sequence Pro40-Pro-Met-Gly-Pro-Arg-Arg-Phe48 (AChE human sequence). The antibodies, however, also reacted with the proline-containing sequences Pro78-Gly-Phe-Glu-Gly-Thr-Glu 84 and Pro88-Asn-Arg-Glu-Leu-Ser-Glu-Asp95. Antibodies that recognized other features of the PAS area but not the Arg 90-Gly-Leu-Ser-Glu-Asp95 motif interfered neither with laminin binding nor with cell adhesion. These results define sites for the interaction of AChE and laminin and suggest that the interaction plays a role in cell adhesion. They also suggest the strong probability of functional redundancy between AChE and other molecules in early development, particularly heparan sulfate proteoglycans, which may explain the survival of the AChE-knockout mouse. © The Authors.
dc.description.versionArticle
dc.identifier.citationBiochemical Journal
dc.identifier.citation411
dc.identifier.citation3
dc.identifier.issn2646021
dc.identifier.other10.1042/BJ20071404
dc.identifier.urihttp://hdl.handle.net/10019.1/12599
dc.subjectAntibodies
dc.subjectCell adhesion
dc.subjectHydrolysis
dc.subjectRats
dc.subjectAcetylcholinesterase
dc.subjectNeunte outgrowth
dc.subjectPeripheral anionic site (PAS)
dc.subjectEnzyme activity
dc.subjectacetylcholinesterase
dc.subjectdocking protein
dc.subjectheparin
dc.subjectlaminin 1
dc.subjectlaminin binding protein
dc.subjectsynthetic peptide
dc.subjectAG 73
dc.subjectanion
dc.subjectepitope
dc.subjectlaminin
dc.subjectlaminin a
dc.subjectmonoclonal antibody
dc.subjectpeptide fragment
dc.subjectunclassified drug
dc.subjectarticle
dc.subjectcell adhesion
dc.subjectconformational transition
dc.subjectenzyme binding
dc.subjectenzyme linked immunosorbent assay
dc.subjectmolecular interaction
dc.subjectpriority journal
dc.subjectprotein analysis
dc.subjectamino acid sequence
dc.subjectanimal
dc.subjectbinding competition
dc.subjectchemical structure
dc.subjectchemistry
dc.subjecthuman
dc.subjectimmunology
dc.subjectmetabolism
dc.subjectmolecular genetics
dc.subjectmouse
dc.subjectprotein binding
dc.subjectprotein quaternary structure
dc.subjectprotein tertiary structure
dc.subjectsequence alignment
dc.subjectAcetylcholinesterase
dc.subjectAmino Acid Sequence
dc.subjectAnimals
dc.subjectAnions
dc.subjectAntibodies, Monoclonal
dc.subjectBinding, Competitive
dc.subjectEpitopes
dc.subjectHeparin
dc.subjectHumans
dc.subjectLaminin
dc.subjectMice
dc.subjectModels, Molecular
dc.subjectMolecular Sequence Data
dc.subjectPeptide Fragments
dc.subjectProtein Binding
dc.subjectProtein Structure, Quaternary
dc.subjectProtein Structure, Tertiary
dc.subjectSequence Alignment
dc.titleInteraction of acetylcholinesterase with the G4 domain of the laminin α1-chain
dc.typeArticle
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