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Drosophila OTK Is a Glycosaminoglycan-Binding Protein with High Conformational Flexibility.

ABSTRACT: The transmembrane protein OTK plays an essential role in plexin and Wnt signaling during Drosophila development. We have determined a crystal structure of the last three domains of the OTK ectodomain and found that OTK shows high conformational flexibility resulting from mobility at the interdomain interfaces. We failed to detect direct binding between Drosophila Plexin A (PlexA) and OTK, which was suggested previously. We found that, instead of PlexA, OTK directly binds semaphorin 1a. Our binding analyses further revealed that glycosaminoglycans, heparin and heparan sulfate, are ligands for OTK and thus may play a role in the Sema1a-PlexA axon guidance system.

SUBMITTER: Rozbesky D

PROVIDER: S-EPMC7203548 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Drosophila OTK Is a Glycosaminoglycan-Binding Protein with High Conformational Flexibility.

Rozbesky Daniel D Monistrol Jim J Jain Vitul V Hillier James J Padilla-Parra Sergi S Jones E Yvonne EY

Structure (London, England : 1993) 20200317 5

The transmembrane protein OTK plays an essential role in plexin and Wnt signaling during Drosophila development. We have determined a crystal structure of the last three domains of the OTK ectodomain and found that OTK shows high conformational flexibility resulting from mobility at the interdomain interfaces. We failed to detect direct binding between Drosophila Plexin A (PlexA) and OTK, which was suggested previously. We found that, instead of PlexA, OTK directly binds semaphorin 1a. Our bindi ...[more]

PMID: 32187531

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