In molecular biology, the haemolymph juvenile hormone-binding protein (JHPB) family of proteins consists of several insect specific haemolymph juvenile hormone binding proteins. Juvenile hormone (JH) has a profound effect on insects. It regulates embryogenesis, maintains the status quo of larva development and stimulates reproductive maturation in the adult forms. JH is transported from the sites of its synthesis to target tissues by a haemolymph carrier called juvenile hormone-binding protein (JHBP). JHBP protects the JH molecules from hydrolysis by non-specific esterases present in the insect haemolymph.[1] The crystal structure of the JHBP from Galleria mellonella (greater wax moth) shows an unusual fold consisting of a long alpha-helix wrapped in a much curved antiparallel beta-sheet. The folding pattern for this structure closely resembles that found in some tandem-repeat mammalian lipid-binding and bactericidal permeability-increasing proteins, with a similar organisation of the major cavity and a disulfide bond linking the long helix and the beta-sheet. It would appear that JHBP forms two cavities, only one of which, the one near the N- and C-termini, binds the hormone; binding induces a conformational change, of unknown significance.[2][3]
| Haemolymph juvenile hormone-binding protein | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| Symbol | JHBP | ||||||||
| Pfam | PF06585 | ||||||||
| InterPro | IPR010562 | ||||||||
| |||||||||
References
edit- ^ Kolodziejczyk R, Kochman M, Bujacz G, Dobryszycki P, Ozyhar A, Jaskolski M (March 2003). "Crystallization and preliminary crystallographic studies of juvenile hormone-binding protein from Galleria mellonella haemolymph". Acta Crystallogr. D. 59 (Pt 3): 519–21. Bibcode:2003AcCrD..59..519K. doi:10.1107/S0907444902022904. PMID 12595713.
- ^ Kolodziejczyk R, Bujacz G, Jakob M, Ozyhar A, Jaskolski M, Kochman M (March 2008). "Insect juvenile hormone binding protein shows ancestral fold present in human lipid-binding proteins". J. Mol. Biol. 377 (3): 870–81. doi:10.1016/j.jmb.2008.01.026. PMID 18291417.
- ^ Palli SR, Touhara K, Charles JP, Bonning BC, Atkinson JK, Trowell SC, Hiruma K, Goodman WG, Kyriakides T, Prestwich GD (June 1994). "A nuclear juvenile hormone-binding protein from larvae of Manduca sexta: a putative receptor for the metamorphic action of juvenile hormone". Proc. Natl. Acad. Sci. U.S.A. 91 (13): 6191–5. Bibcode:1994PNAS...91.6191P. doi:10.1073/pnas.91.13.6191. PMC 44164. PMID 8016136.