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Grb7-SH2 domain dimerisation is affected by a single point mutation.

Corrine J Porter·Matthew C J Wilce·Joel P Mackay·Peter Leedman·Jackie A Wilce
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Abstract

Growth factor receptor bound protein 7 (Grb7) is an adaptor protein that is co-overexpressed and forms a tight complex with the ErbB2 receptor in a number of breast tumours and breast cancer cell lines. The interaction of Grb7 with the ErbB2 receptor is mediated via its Src homology 2 (SH2) domain. Whilst most SH2 domains exist as monomers, recently reported studies have suggested that the Grb7-SH2 domain exists as a homodimer. The self-association properties of the Grb7-SH2 domain were therefore studied using sedimentation equilibrium ultracentrifugation. Analysis of the data demonstrated that the Grb7-SH2 domain is dimeric with a dissociation constant of approximately 11 muM. We also demonstrate, using size-exclusion chromatography, that mutation of phenylalanine 511 to an arginine produces a monomeric form of the Grb7-SH2 domain. This mutation represents the first step in the engineering of a Grb7-SH2 domain with good solution properties for further biophysical and structural investigation.

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ArginineBiophysicsCell Line, TumorChromatographyDimerizationDose-Response Relationship, DrugEscherichia coliHumansHydrogen-Ion ConcentrationModels, StatisticalMolecular ConformationMutagenesis, Site-DirectedMutationPhenylalaninePlasmidsPoint MutationProtein BindingProtein EngineeringProtein Structure, TertiaryUltracentrifugationsrc Homology DomainsJournal ArticleResearch Support, Non-U.S. Gov't

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Corrine J Porter, Matthew C J Wilce, Joel P Mackay, Peter Leedman, Jackie A Wilce. 2005-04-20. Grb7-SH2 domain dimerisation is affected by a single point mutation.. https://doi.org/10.1007/s00249-005-0480-1

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