O'Connell Nichole E, Lelli Katherine, Mann Richard S, Palmer Arthur G
Department of Biochemistry and Molecular Biophysics, Columbia University, 630 West 168th Street, New York, NY 10032, United States.
Department of Biochemistry and Molecular Biophysics, Columbia University, 630 West 168th Street, New York, NY 10032, United States.
FEBS Lett. 2015 Oct 24;589(21):3237-41. doi: 10.1016/j.febslet.2015.09.020. Epub 2015 Oct 3.
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.
天冬酰胺的自发脱酰胺作用是蛋白质的一种非酶促翻译后修饰。果蝇同源框转录因子性梳减少（Scr）的主要脱酰胺位点是第321位天冬酰胺残基。通过HNCACB三共振核磁共振光谱检测到主要脱酰胺产物异天冬氨酸的形成。通过拟合（15）N-（1）H HSQC核磁共振光谱时间序列中天冬酰胺NH2侧链信号的衰减来定量脱酰胺速率。如通过电泳迁移率变动分析所确定的，Scr的脱酰胺形式以降低的亲和力与特定的DNA靶序列结合。
