Email updates   Highly Accessed Protein family review  The
Frizzled family: receptors for multiple signal transduction
pathways  Hui-Chuan Huang1 and Peter S Klein12*  Author
Affiliations  1 Department of Medicine, University of
Pennsylvania School of Medicine, 415 Curie Blvd. Philadelphia,
PA 19104-6148, USA  2 Howard Hughes Medical Institute,
University of Pennsylvania School of Medicine, 415 Curie Blvd.
Philadelphia, PA 19104-6148, USA  For all author emails, please
log on.  Genome Biology 2004, 5:234  doi:10.1186/gb-2004-5-7-234
Published:14 June 2004  © 2004 BioMed Central Ltd   Frizzled
genes encode integral membrane proteins that function in
multiple signal transduction pathways. They have been identified
in diverse animals, from sponges to humans. The family is
defined by conserved structural features, including seven
hydrophobic domains and a cysteine-rich ligand-binding domain.
Frizzled proteins are receptors for secreted Wnt proteins, as
well as other ligands, and also play a critical role in the