title: N-glycosylation alters cadherin-mediated intercellular binding kinetics.
abstract: We present direct evidence that the N-glycosylation state of neural cadherin impacts the intrinsic kinetics of cadherin-mediated intercellular binding. Micropipette manipulation measurements quantified the effect of N-glycosylation mutations on intercellular binding dynamics. The wild-type protein exhibits a two-stage binding process in which a fast, initial binding step is followed by a short lag and second, slower transition to the final binding stage. Mutations that ablate N-glycosylation at three sites on the extracellular domains 2 and 3 of neural cadherin alter this kinetic fingerprint. Glycosylation does not affect the affinities between the adhesive N-terminal domains, but instead modulates additional cadherin interactions, which govern the dynamics of intercellular binding. These results, together with previous findings that these hypo-glycosylation mutations increase the prevalence of cis dimers on cell membranes, suggest a binding mechanism in which initial adhesion is followed by additional cadherin interactions, which enhance binding but are modulated by N-glycosylation. Given that oncogene expression drives specific changes in N-glycosylation, these results provide insight into possible mechanisms altering cadherin function during tumor progression.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Langer
authors.forename: Huabei
authors.initials: H
authors.lastname: Guo
authors.forename: Nitesh
authors.initials: N
authors.lastname: Shashikanth
authors.forename: J Michael
authors.initials: JM
authors.lastname: Pierce
authors.forename: Deborah E
authors.initials: DE
authors.lastname: Leckband
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D016466:CHO Cells; D015820:Cadherins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002448:Cell Adhesion; D006224:Cricetinae; D004912:Erythrocytes / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D007700:Kinetics; D051379:Mice; D011485:Protein Binding; D017434:Protein Structure, Tertiary
chemical_list: D015820:Cadherins