Research Abstract

カイコ(Bombyx mori)のJHBPによる血リンパでのJH送達の構造機構

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

2011年10月28日 Scientific Reports 1 : 133 doi: 10.1038/srep00133


鈴木 倫太郎1*, 藤本 瑞1*, 塩月 孝博2 土屋 渉1, 門間 充1, 多勢 祥1, 宮澤 光博3 & 山崎 俊正1

  1. 独立行政法人 農業生物資源研究所 農業生物先端ゲノム研究センター 生体分子研究ユニット
  2. 独立行政法人 農業生物資源研究所 昆虫科学研究領域 昆虫成長制御研究ユニット
  3. 独立行政法人 農業生物資源研究所 遺伝子組換え研究センター 昆虫機能研究開発ユニット
    *The first two authors contributed equally to this work.
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.