Global serum glycoform profiling for the investigation of dystroglycanopathies & Congenital Disorders of Glycosylation

Molecular Genetics and Metabolism Reports

Gabriela Carreno¹  Kevin Mills¹  Philippa Mills¹  Stephanie Grunewald¹  Emily Bliss¹  Wendy E. Heywood¹  Jale Yuzugulen¹  Peter T. Clayton¹  Silvia Torelli²  Francesco Muntoni²  Neil J. Sebire³  Viki C. Worthington⁴ 

[1] Centre for Inborn Errors of Metabolism, Great Ormond Street Hospital, Great Ormond Street, London WC1N 3JH, UK;Dubowitz Neuromuscular Centre, UCL Institute of Child Health and Great Ormond Street Hospital, NHS Foundation Trust, London WC1N 1EH, UK;Histopathology Department Great Ormond Street Hospital, NHS Foundation Trust, London WC1N 1EH, UK;Neuroimmunology & CSF Laboratory, Institute of Neurology, Queen Square, London WC1N 3BG, UK;

关键词: Congenital Disorders of Glycosylation;    Dystroglycanopathies, 2D DIGE;    C1-esterase inhibitor;    Glycoproteome;    α1-Antitrypsin;   

DOI  :  10.1016/j.ymgmr.2016.03.002

来源: DOAJ

【 摘 要 】

The Congenital Disorders of Glycosylation (CDG) are an expanding group of genetic disorders which encompass a spectrum of glycosylation defects of protein and lipids, including N- & O-linked defects and among the latter are the muscular dystroglycanopathies (MD). Initial screening of CDG is usually based on the investigation of the glycoproteins transferrin, and/or apolipoprotein CIII. These biomarkers do not always detect complex or subtle defects present in older patients, therefore there is a need to investigate additional glycoproteins in some cases. We describe a sensitive 2D-Differential Gel Electrophoresis (DIGE) method that provides a global analysis of the serum glycoproteome. Patient samples from PMM2-CDG (n = 5), CDG-II (n = 7), MD and known complex N- & O-linked glycosylation defects (n = 3) were analysed by 2D DIGE. Using this technique we demonstrated characteristic changes in mass and charge in PMM2-CDG and in charge in CDG-II for α1-antitrypsin, α1-antichymotrypsin, α2-HS-glycoprotein, ceruloplasmin, and α1-acid glycoproteins 1&2. Analysis of the samples with known N- & O-linked defects identified a lower molecular weight glycoform of C1-esterase inhibitor that was not observed in the N-linked glycosylation disorders indicating the change is likely due to affected O-glycosylation. In addition, we could identify abnormal serum glycoproteins in LARGE and B3GALNT2-deficient muscular dystrophies. The results demonstrate that the glycoform pattern is varied for some CDG patients not all glycoproteins are consistently affected and analysis of more than one protein in complex cases is warranted. 2D DIGE is an ideal method to investigate the global glycoproteome and is a potentially powerful tool and secondary test for aiding the complex diagnosis and sub classification of CDG. The technique has further potential in monitoring patients for future treatment strategies. In an era of shifting emphasis from gel- to mass-spectral based proteomics techniques, we demonstrate that 2D-DIGE remains a powerful method for studying global changes in post-translational modifications of proteins.

【 授权许可】

Unknown