Analysis of mutation-originated gain-of-glycosylation using mass
spectrometry-based N-glycoproteomics
Abstract
RATIONALE: A general N-glycoproteomics analysis pipeline has
been established for characterization of mutation-related
gain-of-glycosylation (GoG) at intact N-glycopeptide molecular level,
generating comprehensive site and structure information of
N-glycosylation. METHODS: This study focus on
mutation-originated gain-of-glycosylation using mass spectrometry-based
N-glycoproteomics analysis workflow. In brief, GoG intact N-glycopeptide
databases were built, consisting of 2,701 proteins (potential GoG
N-glycosites and amino acids derived from MUTAGEN, VARIANT and VAR_SEQ
in UniProt) and 6,709 human N-glycans (≤50 sequence isomers per
monosaccharide composition). We employed the site- and
structure-specific N-glycoproteomics workflow utilizing intact
N-glycopeptides search engine GPSeeker to identify GoG intact
N-glycopeptides from parental breast cancer stem cells (MCF-7 CSCs) and
adriamycin-resistant breast cancer stem cells (MCF-7/ADR CSCs).
RESULTS: With the criteria of spectrum-level FDR control of
≤1%, we identified 88 and 96 GoG intact N-glycopeptides corresponding
to 38 and 36 intact N-glycoproteins from MCF-7 CSCs and MCF-7/ADR CSCs,
respectively. Among KEGG annotation of GoG N-glycoproteins, DNA
polymerase eta (POLH), serine-protein kinase ATM (ATM) and cellular
tumor antigen p53 (P53) were enriched in platinum drug resistance signal
pathway. ATM, P53 and G2 and S phase-expressed protein 1 (GTSE1) were
associated with p53 signaling pathway. CONCLUSIONS: The
integration of site- and structure-specific N-glycoproteomics approach,
conjugating with GoG characterization, provides a universal workflow for
revealing comprehensive N-glycosite and N-glycan structure information
of gain-of-glycosylation. The analysis of mutation-originated gain-of
glycosylation can be extended GoG characterization to all the other
N-glycoproteome systems including complex clinical tissues and body
fluids.