The EGF-TM7 family: a postgenomic view

Immunogenetics. 2004 Jan;55(10):655-66. doi: 10.1007/s00251-003-0625-2. Epub 2003 Nov 27.


With the human and mouse genome projects now completed, the receptor repertoire of mammalian cells has finally been elucidated. The EGF-TM7 receptors are a family of class B seven-span transmembrane (TM7) receptors predominantly expressed by cells of the immune system. Within the large TM7 superfamily, the molecular structure and ligand-binding properties of EGF-TM7 receptors are unique. Derived from the processing of a single polypeptide, they are expressed at the cell surface as heterodimers consisting of a large extracellular region associated with a TM7 moiety. Through a variable number of N-terminal epidermal growth factor (EGF)-like domains, EGF-TM7 receptors interact with cellular ligands such as CD55 and chondroitin sulfate. Recent in vivo studies demonstrate a role of the EGF-TM7 receptor CD97 in leukocyte migration. The different number of EGF-TM7 genes in man compared with mice, the chimeric nature of EMR2 and the inactivation of human EMR4 point toward a still-evolving receptor family. Here we discuss the currently available information on this intriguing receptor family.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Movement
  • Epidermal Growth Factor / chemistry
  • Epidermal Growth Factor / genetics*
  • Epidermal Growth Factor / physiology
  • Evolution, Molecular
  • GTP-Binding Proteins / physiology
  • Humans
  • Membrane Proteins / chemistry
  • Membrane Proteins / classification
  • Membrane Proteins / genetics*
  • Membrane Proteins / physiology
  • Mice
  • Models, Molecular
  • Molecular Sequence Data
  • Multigene Family*
  • Muscle, Smooth / cytology
  • Muscle, Smooth / metabolism
  • Myeloid Cells / metabolism
  • Primates / genetics
  • Protein Conformation
  • Protein Structure, Tertiary
  • Receptors, G-Protein-Coupled / genetics
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • Species Specificity


  • ADGRE4P protein, human
  • Emr4 protein, mouse
  • Membrane Proteins
  • Receptors, G-Protein-Coupled
  • Epidermal Growth Factor
  • GTP-Binding Proteins