title: Asparagine deamidation reduces DNA-binding affinity of the Drosophila melanogaster Scr homeodomain.
abstract: Spontaneous deamidation of asparagine is a non-enzymatic post-translational modification of proteins. Residue Asn 321 is the main site of deamidation of the Drosophila melanogaster Hox transcription factor Sex Combs Reduced (Scr). Formation of iso-aspartate, the major deamidation product, is detected by HNCACB triple-resonance NMR spectroscopy. The rate of deamidation is quantified by fitting the decay of Asn NH2 side-chain signals in a time-series of (15)N-(1)H HSQC NMR spectra. The deamidated form of Scr binds to specific DNA target sequences with reduced affinity as determined by an electrophoretic mobility shift assay.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Columbia University, 630 West 168th Street, New York, NY 10032, United States.
authors.forename: Nichole E
authors.initials: NE
authors.lastname: O'Connell
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Columbia University, 630 West 168th Street, New York, NY 10032, United States.
authors.forename: Katherine
authors.initials: K
authors.lastname: Lelli
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Columbia University, 630 West 168th Street, New York, NY 10032, United States.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Mann
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Columbia University, 630 West 168th Street, New York, NY 10032, United States. Electronic address: agp6@columbia.edu.
authors.forename: Arthur G
authors.initials: AG
authors.lastname: Palmer
mesh_terms: D000818:Animals; D001216:Asparagine / Q000378:metabolism*; D001665:Binding Sites; D004247:DNA / Q000378:metabolism*; D029721:Drosophila Proteins / Q000737:chemistry* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism*; D026581:Isoaspartic Acid / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; D026581:Isoaspartic Acid; C059627:Scr protein, Drosophila; D014157:Transcription Factors; D001216:Asparagine; D004247:DNA
keywords: Asparagine deamidation; DNA binding; Dissociation constant; Hox transcription factor; NMR spectroscopy; Sex Combs Reduced