Lipophorins lipid transport

Chino, H. 1985. Lipid transport Biochemistry of hemolymph lipophorin. In Comprehensive Insect Physiology, Biochemistry, and Pharmacology, eds. Kerkut G. A. and Gilbert L. I., Oxford Pergamon Press, 10 115-134. 

The third, and perhaps least understood, mechanism regulating contact pheromone production involves its transport to the cuticular surface. The detection of large amounts of hydrocarbons and pheromone internally, within the hemolymph, prompted an examination of lipid transport in B. germanica. Gu et al. (1995) and Sevala etal. (1997) isolated and purified a high density lipoprotein, lipophorin, that carries hydrocarbons, contact pheromone, and JH within the hemolymph. The accumulated evidence supports the idea that the hydrocarbons and contact pheromone components are produced by oenocytes within the abdominal integument, carried by lipophorin, and differentially deposited in the cuticle and ovaries (Fan et al.,... 

A third group of lipid-binding proteins have a four-helix bundle structure. They include the insect lipophorins, which transport diacylglycerols in the hemolymph (see main text), and nonspecific lipid carriers of green plants.q An 87-residue four-helix protein with a more open structure binds acyl-coenzyme A molecules in liver.r... 

Chino H. (1997) Physiological significance of lipid transport by lipophorin for longdistance flight in insects. Comp. Biochem. Physiol. B 117, 455-461. 

Chino H. and Downer R. G. H. (1982) Insect hemolymph lipophorin a mechanism of lipid transport in insects. Adv. Biophys. 15, 67-92. 

Soulages J. L. and Wells M. A. (1994) Lipophorin the structure of an insect lipoprotein and its role in lipid transport in insects. Adv. Protein. Chem. 45, 371-415. 

Chino, H. (1985). Lipid transport biochemistry of hemolymph lipophorin. In... 

Atella, G.C., Silva-Neto, A.C., Golodne, D.M., Arehn, S. and Shahabuddin, M. (2006). Anopheles gambiae lipophorin Characterization and role in lipid transport to developing oocyte. Insect Biochem. Mol. Ecol., 36, 375-386. 

Insects use camouflage coloration as a means of avoiding predation. The green color of the tobacco hornworm larvae, (Manduca sexta) can be separated into constituent blue and yellow components. The water soluble blue component is the biliprotein, insecticyanin. The yellow color is derived from lipoprotein bound carotenes. This lipoprotein, lipophorin, is the major lipid transport vehicle in insect hemolymph. In addition to transporting dietary lipid, lipophorin is also involved in the transport of lipophilic insecticides. Nearly all the recovered radioactivity in hemolymph from topically applied [14c] ddt is associated with lipophorin. Lipophorin of adult M. sexta is larger, less dense and is associated with small amounts of a third, adult specific, apoprotein. Alterations in adult lipophorin density, lipid content and apoprotein stoichiometry can be caused by injection of the decapeptide, adipokinetic hormone. 

LIPOPHORIN THE STRUCTURE OF AN INSECT LIPOPROTEIN AND ITS ROLE IN LIPID TRANSPORT IN INSECTS... 

Vertebrate, especially mammalian, lipoproteins have been extensively studied. In the invertebrate world, only insect lipoproteins have received serious attention. Whereas vertebrates rely on a battery of lipoproteins (chylomicrons, very low-density lipoproteins, low-density lipoproteins, and high-density lipoproteins) to effect lipid transport, insects use primarily a single type of lipoprotein, lipophorin, for lipid transport. Lipophorin is both more versatile than vertebrate lipoproteins in terms of the diverse lipids it transports and more efficient than vertebrate lipoproteins in that, for the most part, it delivers lipids to tissues without being internalized and destroyed. We believe that new insights can be obtained from an understanding of insect lipoproteins, and in this article we review the current state of knowledge about the structure and metabolism of lipophorins. 

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