Skip to content
2000
Volume 27, Issue 11
  • ISSN: 0929-8665
  • E-ISSN: 1875-5305

Abstract

Background: B-cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) can activate signaling pathways by binding to specific receptors. BR3 (BAFF receptor) shows a unique selectivity for BAFF ligand, while B-cell maturation antigen (BCMA) exhibits a stronger interaction between APRIL-BCMA rather than BAFF-BCMA interaction. Objective: The combined domains were fused with IgG1 Fc to better understand which domain affects the selective interaction of the receptor with BAFF and APRIL. Methods: Since BR3 and BCMA both contain cysteine-rich repeat domains (CRD) with DxL motif, the binding domains of BR3 and BCMA were segmented into two parts in this study. BR3-1 (CFDLLVRHGVAC) and BCMA-1 (YFDSLLHACIPC) contained the conservative DxL motif, while BR3-2 (GLLRTPRPKPA) and BCMA-2 (QLRCSSNTPPLT) were adjacent to the CRDs yet still joined with BR3-1 and BCMA-1. Affinity between all possible combinations was then tested. Results: The affinity of BR3-1-BCMA-2-Fc and BR3-1-BR3-2-Fc for BAFF was higher than BCMA-1-BR3-2-Fc and BCMA-1-BCMA-2-Fc. Moreover, BR3-1-BCMA-2-Fc and BCMA-1-BCMA- 2-Fc had affinity for APRIL, while BR3-1-BR3-2-Fc and BCMA-1-BR3-2-Fc hardly interacted with APRIL. Conclusion: BR3-1 region played a key role for interaction with BAFF, while BCMA-1 region exhibited weaker binding with BAFF. BCMA-2 region having an α-helix might contribute towards selectivity of APRIL-BCMA binding and BR3-2 rigid region had deleterious effects on the APRIL-BR3 interaction. These results provide comprehensive insights of the mechanism of selective interactions, and may promote specific antagonist design in the future.

Loading

Article metrics loading...

/content/journals/ppl/10.2174/0929866527666200413101757
2020-11-01
2025-06-13
Loading full text...

Full text loading...

/content/journals/ppl/10.2174/0929866527666200413101757
Loading

  • Article Type:
    Research Article
Keyword(s): APRIL; BAFF; BCMA; BR3; mechanism; selective binding
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error
Please enter a valid_number test