PDBsum entry 3aos

Hormone binding protein

PDB id: 3aos

Contents

Protein chains

221 a.a.

Ligands

JH2 ×2

Waters ×124

PDB id:

3aos

Name:

Hormone binding protein

Title:

Crystal structure of juvenile hormone binding protein from silkworm in complex with jh ii

Structure:

Hemolymph juvenile hormone binding protein. Chain: a, b. Fragment: unp residues 19-243. Engineered: yes

Source:

Bombyx mori. Silk moth, silkworm. Organism_taxid: 7091. Gene: hjhbp. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.20Å R-factor: 0.242 R-free: 0.291

Authors:

Z.Fujimoto,R.Suzuki,T.Shiotsuki,M.Momma,T.Yamazaki

Key ref:

R.Suzuki et al. (2011). Structural mechanism of JH delivery in hemolymph by JHBP of silkworm, Bombyx mori. Sci Rep, 1, 133. PubMed id: 22355650

Date:

06-Oct-10 Release date: 12-Oct-11

Protein chains

Q9U556  (Q9U556_BOMMO) -  Hemolymph juvenile hormone binding protein from Bombyx mori

Seq: 243 a.a.

Struc: 221 a.a.

Sci Rep 1:133 (2011)

PubMed id: 22355650

Structural mechanism of JH delivery in hemolymph by JHBP of silkworm, Bombyx mori.

R.Suzuki, Z.Fujimoto, T.Shiotsuki, W.Tsuchiya, M.Momma, A.Tase, M.Miyazawa, T.Yamazaki.

ABSTRACT

Juvenile hormone (JH) plays crucial roles in many aspects of the insect life. All the JH actions are initiated by transport of JH in the hemolymph as a complex with JH-binding protein (JHBP) to target tissues. Here, we report structural mechanism of JH delivery by JHBP based upon the crystal and solution structures of apo and JH-bound JHBP. In solution, apo-JHBP exists in equilibrium of multiple conformations with different orientations of the gate helix for the hormone-binding pocket ranging from closed to open forms. JH-binding to the gate-open form results in the fully closed JHBP-JH complex structure where the bound JH is completely buried inside the protein. JH-bound JHBP opens the gate helix to release the bound hormone likely by sensing the less polar environment at the membrane surface of target cells. This is the first report that provides structural insight into JH signaling.