Mutation analysis of the short cytoplasmic domain of the cell-cell adhesion molecule CEACAM1 identifies residues that orchestrate actin binding and lumen formation

J Biol Chem. 2007 Feb 23;282(8):5749-60. doi: 10.1074/jbc.M610903200. Epub 2006 Dec 27.


CEACAM1-4S (carcinoembryonic antigen cell adhesion molecule 1, with 4 ectodomains and a short, 12-14 amino acid cytoplasmic domain) mediates lumen formation via an apoptotic and cytoskeletal reorganization mechanism when mammary epithelial cells are grown in a three-dimensional model of mammary morphogenesis. We show by quantitative yeast two-hybrid, BIAcore, NMR HSQC and STD, and confocal analyses that amino acids phenylalanine (Phe(454)) and lysine (Lys(456)) are key residues that interact with actin orchestrating the cytoskeletal reorganization. A CEACAM1 membrane model based on vitamin D-binding protein that predicts an interaction of Phe(454) at subdomain 3 of actin was supported by inhibition of binding of actin to vitamin D-binding protein by the cytoplasmic domain peptide. We also show that residues Thr(457) and/or Ser(459) are phosphorylated in CEACAM1-transfected cells grown in three-dimensional culture and that mutation analysis of these residues (T457A/S459A) or F454A blocks lumen formation. These studies demonstrate that a short cytoplasmic domain membrane receptor can directly mediate substantial intracellular signaling.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Actins / genetics
  • Actins / metabolism*
  • Amino Acid Substitution
  • Antigens, CD / genetics
  • Antigens, CD / metabolism*
  • Apoptosis / physiology
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism*
  • Cell Culture Techniques
  • Cytoskeleton / genetics
  • Cytoskeleton / metabolism
  • Epithelial Cells / cytology
  • Epithelial Cells / metabolism*
  • Female
  • HeLa Cells
  • Humans
  • Jurkat Cells
  • Mammary Glands, Human / cytology
  • Mammary Glands, Human / metabolism*
  • Models, Molecular*
  • Organogenesis / physiology
  • Protein Binding / physiology
  • Protein Structure, Tertiary / physiology
  • Signal Transduction / physiology*
  • Vitamin D-Binding Protein / genetics
  • Vitamin D-Binding Protein / metabolism


  • Actins
  • Antigens, CD
  • CD66 antigens
  • Cell Adhesion Molecules
  • Vitamin D-Binding Protein