Juvenile hormone binding protein traffic -- Interaction with ATP synthase and lipid transfer proteins.
Juvenile hormone (JH) controls insect development, metamorphosis and reproduction. In insect hemolymph a significant proportion of JH is bound to juvenile hormone binding protein (JHBP), which serves as a carrier supplying the hormone to the target tissues. To shed some light on JHBP passage within insect tissues, the interaction of this carrier with other proteins from Galleria mellonella (Lepidoptera) was investigated. Our studies revealed the presence of JHBP within the tracheal epithelium and fat body cells in both the membrane and cytoplasmic sections. We found that the interaction between JHBP and membrane proteins occurs with saturation kinetics and is specific and reversible. ATP synthase was indicated as a JHBP membrane binding protein based upon SPR-BIA and MS analysis. It was found that in G. mellonella fat body, this enzyme is present in mitochondrial fraction, plasma membranes and cytosol as well. In the model system containing bovine F(1) ATP synthase and JHBP, the interaction between these two components occurs with K(d)=0.86 nM. In hemolymph we detected JHBP binding to apolipophorin, arylphorin and hexamerin. These results provide the first demonstration of the physical interaction of JHBP with membrane and hemolymph proteins which can be involved in JHBP molecule traffic.
Zalewska
Marta
M
Department of Biochemistry, Faculty of Chemistry, Wrocław University of Technology, Wybrzeze Wyspiańskiego 27, 50-370, Wrocław, Poland.
Kochman
Agata
A
Estève
Jean-Pierre
JP
Lopez
Frédéric
F
Chaoui
Karima
K
Susini
Christiane
C
Ozyhar
Andrzej
A
Kochman
Marian
M
D000818:Animals; D001053:Apolipoproteins / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism*; D005216:Fat Body / Q000737:chemistry / Q000648:ultrastructure; D006458:Hemolymph / Q000378:metabolism; D019476:Insect Proteins / Q000378:metabolism*; D007605:Juvenile Hormones / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D025261:Mitochondrial Proton-Translocating ATPases / Q000378:metabolism*; D009036:Moths; D021381:Protein Transport / Q000502:physiology*; D020349:Surface Plasmon Resonance
D001053:Apolipoproteins; D002352:Carrier Proteins; D019476:Insect Proteins; D007605:Juvenile Hormones; D008565:Membrane Proteins; C042470:apolipophorin III; C035606:juvenile hormone-binding protein, insect; C030363:lipid transfer protein; C474451:F1F0-ATP synthase; D025261:Mitochondrial Proton-Translocating ATPases