|KIM, YONGGYUN - Andong National University|
Submitted to: Frontiers in Endocrinology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/2011
Publication Date: 12/30/2011
Citation: Stanley, D.W., Kim, Y. 2011. Prostaglandins and their receptors in insect biology. Frontiers in Endocrinology. 2:105.
Interpretive Summary: The concept of biological control of insects is based on the idea that direct application of some of these pathogens and parasites can reduce pest insect populations and the economic damage due to pest insects. The problem, however, is the efficiency of these organisms in biological control programs is limited by insect immune defense reactions to challenge. One approach to improving the efficiency of biocontrol agents would be to somehow disable insect immune reactions to viral, bacterial, fungal and parasitic infections. We have discovered one group of molecules that mediate insect cellular immune reactions. In this paper we present a background description of insect immunity and discuss the roles of the molecules we discovered in mediating insect immune reactions to infection. In doing so, we join two disparate concepts in insect science: one is research designed to understand how chemical mediators act in cellular immunity. The other is research designed to understand how chemical treatments can disable insect immunity. This new conjunction will be directly useful to scientists who are working to improve the efficacy of biological control methods. The ensuing improved biological control methods enhance long-term environmental and agricultural sustainability. These enhancements will benefit agricultural producers and the people who consume their products.
Technical Abstract: We treat the biological significance of prostaglandins (PGs) and their known receptors in insect biology. PGs and related eicosanoids are oxygenated derivatives of arachidonic acid (AA) and two other C20 polyunsaturated fatty acids. PGs are mostly appreciated in the context of biomedicine, but a growing body of literature indicates the biological significance of these compounds extends throughout the animal kingdom, and possibly beyond. PGs act in several crucial areas of insect biology. In reproduction, a specific PG, PGE2, releases oviposition behavior in most crickets and a few other insect species; PGs also mediate events in egg development in some species, which may represent all insects. PGs play major roles in modulating fluid secretion in Malpighian tubules, rectum and salivary glands, although, again, this has been studied in only a few insect species that may represent the Class. Insect immunity is a very complex defense system. PGs and other eicosanoids mediate a large number of immune reactions to infection and invasion. The actions of most PGs are mediated by specific receptors. Biomedical research has discovered a great deal of knowledge about PG receptors in mammals, including their structures, pharmacology, molecular biology and cellular locations. Studies of PG receptors in insects lag behind the biomedical background, however, recent results hold the promise of accelerated research in this area. A PG receptor has been identified in a class of lepidopteran hemocytes and experimentally linked to the release of prophenoloxidase. We conclude that research into PGs and their receptors in insects will lead to important advances in our understanding of insect biology.