PMID: 16293754

 

    Legend: Sugar

Title : Structure of the quaternary complex of interleukin-2 with its alpha, beta, and gammac receptors

Abstract :
  1. Interleukin-2 ( IL-2 ) is an immunoregulatory cytokine that acts through a quaternary receptor signaling complex containing alpha ( IL-2Ralpha), beta ( IL-2Rbeta ), and common gamma chain (gc) receptors
  2. In the structure of the quaternary ectodomain complex as visualized at a resolution of 2.3 angstroms, the binding of IL-2Ralpha to IL-2 stabilizes a secondary binding site for presentation to IL-2Rbeta
  3. gammac is then recruited to the composite surface formed by the IL-2 / IL-2Rbeta complex
  4. Consistent with its role as a shared receptor for IL-4 , IL-7 , IL-9 , IL-15 , and IL-21 , gammac forms degenerate contacts with IL-2
  5. The structure of gammac provides a rationale for loss-of-function mutations found in patients with X-linked severe combined immunodeficiency diseases (X-SCID)
  6. This complex structure provides a framework for other gammac-dependent cytokine- receptor interactions and for the engineering of improved IL-2 therapeutics