PMID: 1740433

 

    Legend: Gene, Sites

Title : Identification of novel members of the serum amyloid A protein superfamily as constitutive apolipoproteins of high density lipoprotein

Abstract :
  1. A novel serum amyloid A protein ( SAA ) has been identified as a normal apo lipoprotein component of non-acute phase high density lipoprotein
  2. This novel SAA has been designated "constitutive" SAA (C- SAA ) to distinguish it from "acute phase" SAA (A- SAA )
  3. C- SAA was partially sequenced, and immunochemical analyses indicated that it constitutes a distinct subclass of apolipoproteins within the SAA superfamily
  4. A C- SAA cDNA clone was isolated from a human liver library and sequenced
  5. The clone predicts a pre-C- SAA molecule of 130 residues from which an 18-residue leader peptide is cleaved
  6. The 112-residue mature molecule is 8 residues longer than human A- SAA ; the size difference is due to the presence of an octapeptide between positions 70 and 77 that is not found in the corresponding region of human A- SAA
  7. Paradoxically, octapeptides of similar com position are found at similar positions in the A-SAAs of a number of other species
  8. The C- SAA octapeptide specifies the first two residues of a NSS tripeptide , the only potential N-linked glycosylation site in the molecule
  9. Studies indicate that approximately 50% of these sites are glycosylated, thereby giving rise to two size classes, 14 and 19 kDa, of C- SAA in vivo
  10. Human acute phase liver contains little C- SAA mRNA relative to the levels of A- SAA mRNA, and the treatment of PLC /PRF/5 hepatoma cells with monocyte-conditioned medium does not induce C- SAA mRNA concentrations to detectable levels, in contrast to the massive induction of A- SAA mRNA observed
  11. C- SAA is therefore not a major acute phase reactant
Output (sent_index, trigger, protein, sugar, site):
  • 8. glycosylation, , -, -, site
  • 8. glycosylation, , -, -, tripeptide
  • 9. glycosylated, , -, -, sites
Output(Part-Of) (sent_index, protein, site):
  • 6. SAA, region
  • 8. C-SAA, octapeptide
*Output_Site_Fusion* (sent_index, protein, sugar, site):

 

 

Protein NCBI ID SENTENCE INDEX
serum amyloid A protein 6288 0,1
PLC 3339 10