3HO5: Crystal Structure Of Hedgehog-interacting Protein (hhip) And Sonic Hedgehog (shh) Complex

Hedgehog (Hh) signaling is crucial for many aspects of embryonic development, whereas dysregulation of this pathway is associated with several types of cancer. Hedgehog-interacting protein (Hhip) is a surface receptor antagonist that is equipotent against all three mammalian Hh homologs. The crystal structures of human HHIP alone and bound to Sonic hedgehog (SHH) now reveal that HHIP is comprised of two EGF domains and a six-bladed beta-propeller domain. In the complex structure, a critical loop from HHIP binds the pseudo active site groove of SHH and directly coordinates its Zn2+ cation. Notably, sequence comparisons of this SHH binding loop with the Hh receptor Patched (Ptc1) ectodomains and HHIP- and PTC1-peptide binding studies suggest a 'patch for Patched' at the Shh pseudo active site; thus, we propose a role for Hhip as a structural decoy receptor for vertebrate Hh.
PDB ID: 3HO5Download
MMDB ID: 73920
PDB Deposition Date: 2009/6/1
Updated in MMDB: 2009/06
Experimental Method:
x-ray diffraction
Resolution: 3.01  Å
Source Organism:
Similar Structures:
Biological Unit for 3HO5: monomeric; determined by author and by software (PISA)
Molecular Components in 3HO5
Label Count Molecule
Protein (1 molecule)
Hedgehog-interacting Protein(Gene symbol: HHIP)
Molecule annotation
Chemical (1 molecule)
* Click molecule labels to explore molecular sequence information.

Citing MMDB