PMID: 17395588

 

    Legend: Gene, Sites

Title : O-fucosylation of thrombospondin type 1 repeats in ADAMTS-like-1 / punctin-1 regulates secretion: implications for the ADAMTS superfamily

Abstract :
  1. The ADAMTS superfamily contains several metalloproteases (ADAMTS proteases) as well as ADAMTS-like molecules that lack proteolytic activity
  2. Their common feature is the presence of one or more thrombospondin type-1 repeats (TSRs) within a characteristic modular organization
  3. ADAMTS like-1 / punctin-1 has four TSRs
  4. Previously, O-fucosylation on Ser or Thr mediated by the endoplasmic reticulum-localized enzyme protein-O-fucosyltransferase 2 ( POFUT2 ) was described for TSRs of thrombospondin-1 , properdin , and F-spondin within the sequence Cys-Xaa(1)-Xaa(2)-( Ser/Thr )- Cys-Xaa-Xaa- Gly (where the fucosylated residue is underlined)
  5. On mass spectrometric analysis of tryptic peptides from recombinant secreted human punctin-1 , the appropriate peptides from TSR2 , TSR3 , and TSR4 were found to bear either a fucose monosaccharide ( TSR3 , TSR4) or a fucose-glucose disaccharide ( TSR2 , TSR3 , TSR4)
  6. Although mass spectral analysis did not unambiguously identify the relevant peptide from TSR1 , metabolic labeling of cells expressing TSR1 and the cysteine-rich module led to incorporation of [(3)H]fucose into this construct
  7. Mutation of the putative modified Ser/Thr residues in TSR2 , TSR3 , and TSR4 led to significantly decreased levels of secreted punctin-1
  8. Similarly, expression of punctin-1 in Lec-13 cells that are deficient in conversion of GDP-mannose to GDP-fucose substantially decreased the levels of secreted protein , which were restored upon culture in the presence of exogenous l-fucose
  9. In addition, mutation of the single N-linked oligosaccharide in punctin-1 led to decreased levels of secreted punctin-1
  10. Taken together, the data define a critical role for N-glycosylation and O-fucosylation in the biosynthesis of punctin-1
  11. From a broad perspective, these data suggest that O-fucosylation may be a widespread post-translational modification in members of the ADAMTS superfamily with possible regulatory consequences
Output (sent_index, trigger, protein, sugar, site):
  • 0. O-fucosylation, , ADAMTS-like-1, O-fucosylation, -
  • 0. O-fucosylation, , ADAMTS-like-1, thrombospondin type 1 repeats, -
  • 4. O-fucosylation, , -, Ser, Ser
  • 4. O-fucosylation, , -, Thr, Thr
  • 4. fucosylated, , -, the fucosylated residue, -
  • 5. bear, , -, a fucose monosaccharide, peptides
  • 5. bear, , -, a fucose-glucose disaccharide, peptides
Output(Part-Of) (sent_index, protein, site):
  • 5. TSR2, peptides
  • 5. TSR3, peptides
  • 5. punctin-1, peptides
  • 6. TSR1, peptide
  • 7. TSR2, residues in
  • 7. TSR3, residues in
*Output_Site_Fusion* (sent_index, protein, sugar, site):

 

 

Protein NCBI ID SENTENCE INDEX
punctin-1 92949 0,3,5,7,8,9,10
ADAMTS-like-1 92949 0
F-spondin 10418 4
TSR1 55720 6
TSR3 115939 5,7
TSR2 90121 5,7
ADAMTS like-1 92949 3
protein-O-fucosyltransferase 2 23275 4
POFUT2 23275 4