PMID: 12122212

 

    Legend: Gene, Sites

Title : The crystal structure of human CD21 : Implications for Epstein-Barr virus and C3d binding

Abstract :
  1. Human complement receptor type 2 2 (CD21 ) is the cellular receptor for Epstein-Barr virus (EBV) , a human tumor virus
  2. The N-terminal two short consensus repeats (SCR1- SCR2 ) of the receptor interact with the EBV glycoprotein gp350/220 and also with the natural CD21 ligand C3d
  3. Here we present the crystal structure of the CD21 SCR1- SCR2 fragment in the absence of ligand and demonstrate that it is able to bind EBV
  4. Based on a functional analysis of wild-type and mutant CD21 and molecular modeling, we identify a likely region for EBV attachment and demonstrate that this region is not involved in the interaction with C3d
  5. A comparison with the previously determined structure of CD21 SCR1- SCR2 in complex with C3d shows that, in both cases, CD21 assumes compact V-shaped conformations
  6. However, our analysis reveals a surprising degree of flexibility at the SCR1- SCR2 interface, suggesting interactions between the two domains are not specific
  7. We present evidence that the V-shaped conformation is induced by deglycosylation of the protein , and that physiologic glycosylation of CD21 would result in a more extended conformation, perhaps with additional epitopes for C3d binding
Output (sent_index, trigger, protein, sugar, site):
  • 2. glycoprotein, , glycoprotein, -, -
  • 2. receptor, , receptor, The N-terminal two short consensus repeats, -
  • 7. deglycosylation, , protein, -, -
  • 7. glycosylation, , CD21, -, -
Output(Part-Of) (sent_index, protein, site):
  • 3. SCR2, fragment
  • 3. structure of the CD21, fragment
*Output_Site_Fusion* (sent_index, protein, sugar, site):

 

 

Protein NCBI ID SENTENCE INDEX
SCR2 5937 2,3,5,6
C3d 100861467 0,2,4,5,7
CD21 1380 0,2,4,5,7
2 (CD21 1380 1
structure of the CD21 1380 3
structure of CD21 1380 5