Crystal structure of a scavenger receptor cysteine-rich domain sheds light on an ancient superfamily

Nat Struct Biol. 1999 Mar;6(3):228-32. doi: 10.1038/6669.


Scavenger receptor cysteine-rich (SRCR) domains are found widely in cell surface molecules and in some secreted proteins, where they are thought to mediate ligand binding. We have determined the crystal structure at 2.0 A resolution of the SRCR domain of Mac-2 binding protein (M2BP), a tumor-associated antigen and matrix protein. The structure reveals a curved six-stranded beta-sheet cradling an alpha-helix. Structure-based sequence alignment demonstrates that the M2BP SRCR domain is a valid template for the entire SRCR protein superfamily. This allows an interpretation of previous mutagenesis data on ligand binding to the lymphocyte receptor CD6.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Crystallography, X-Ray
  • Cysteine / chemistry*
  • DNA Primers
  • Ligands
  • Membrane Proteins*
  • Molecular Sequence Data
  • Protein Binding
  • Receptors, Immunologic / chemistry*
  • Receptors, Immunologic / metabolism
  • Receptors, Lipoprotein*
  • Receptors, Scavenger
  • Scavenger Receptors, Class B
  • Sequence Homology, Amino Acid


  • DNA Primers
  • Ligands
  • Membrane Proteins
  • Receptors, Immunologic
  • Receptors, Lipoprotein
  • Receptors, Scavenger
  • Scarb1 protein, mouse
  • Scavenger Receptors, Class B
  • Cysteine

Associated data

  • PDB/1BY2