PMID: 19196183

 

    Legend: Gene, Sites

Title : Identification of N-glycosylation sites on secreted proteins of human hepatocellular carcinoma cells with a complementary proteomics approach

Abstract :
  1. N-linked glycosylation is prevalent in proteins destined for extracellular environments; nearly all secreted proteins are glycosylated
  2. However, with respect to their glycosylation sites , little attention has been paid
  3. Here, we report the analysis of N-glycosylation sites on secreted proteins of human hepatocellular carcinoma cells
  4. For the enrichment of glycopeptides , capture methods with hydrophilic affinity (HA) and hydrazide chemistry (HC) were used complementarily
  5. With the use of both methods in combination with nano-LC- ESI-MS/MS analysis, 300 different glycosylation sites within 194 unique glycoproteins were identified, and 172 glycosites have not been determined experimentally previously
  6. A direct comparison between HA and HC methods was also investigated for the first time
  7. In brief, in terms of selectivity for glycopeptides , HC is superior to HA (92.9% vs 51.3%); however, based on the number of glycosites identified, HA outweighs HC (265 vs 159)
  8. Furthermore, unavoidable contaminants such as actin and bovine serum albumin which are not N-glycosylated could be easily depleted by using this glycoproteomic strategy
  9. As a consequence, more low-abundance and genuinely secreted proteins were identified
  10. Among the glycoproteins identified, alpha-fetoprotein , CD44 and laminin have been reported to be implicated in HCC and its metastasis
Output (sent_index, trigger, protein, sugar, site):
  • 0. N-glycosylation, , -, -, sites
  • 1. glycosylated, , -, all secreted proteins, -
  • 10. glycoproteins, , glycoproteins, -, -
  • 2. glycosylation, , -, -, sites
  • 3. N-glycosylation, , -, -, sites
  • 4. glycopeptides, , -, -, glycopeptides
  • 5. glycoproteins, , glycoproteins, -, -
  • 5. glycosites, , -, -, glycosites
  • 5. glycosylation, , -, -, sites
  • 7. glycopeptides, , -, -, glycopeptides
  • 7. glycosites, , -, -, glycosites
  • 8. N-glycosylated, , albumin, -, -
Output(Part-Of) (sent_index, protein, site):
  • 0. proteins, sites
*Output_Site_Fusion* (sent_index, protein, sugar, site):

 

 

Protein NCBI ID SENTENCE INDEX
CD44 960 10
alpha-fetoprotein 174 10