Trowell S C, Hines E R, Herlt A J, Rickards R W
CSIRO Division of Entomology, Canberra, Australia.
Comp Biochem Physiol B Biochem Mol Biol. 1994 Oct-Nov;109(2-3):339-57. doi: 10.1016/0305-0491(94)90018-3.
The larval haemolymph of the sheep blowfly Lucilia cuprina (Weidemann) contains a juvenile hormone binding protein with a Kd for racemic JH III of 33 +/- 6 nM. The density of the binding sites is 212 +/- 33 pmol/mg haemolymph protein. The binding protein is equally specific for JH III and methyl farnesoate. Some natural juvenoids were ranked for their ability to displace [3H]JH III with JH III > JH II > JH I > JH III acid > JH III diol > JHB3 = no detectable displacement. These data, together with displacement studies for 14 synthetic juvenoids, indicate some characteristics of the JH binding cleft. The binding protein is a high density lipophorin (density = 1.15 g/ml) and has subunit molecular weights of 228 kDa (apolipophorin I) and 70 kDa (apolipophorin II). The N-terminal amino acid sequences of the subunits have no discernible homology to any previously sequenced protein. Lipophorin-specific immunocytochemical staining occurs in a subset of fat body cells.
