The proposed researh will analyze the distribution of juvenile hormone (JH) receptor proteins in fat body nuclei of melanoplus bivittaus. JH stimulates synthesis of egg yolk protein by grasshopper fat body, and JH receptors are thought to convert the hormone signal to activity at the gene level. A combination of methods used to isolate chromatin, nuclear matrix, and steroid acceptor sites from chromatin will be adapted to analyze JH receptors. Agents such as ionic and non-ionic detergents, neutral and chaotropic salts, and site specific enzymes will be used along with immunological techniques and Western blots currently being developed to simplify receptor identification. Tissues from females, males, and nymphs will be used to judge the physiological importance of receptor distribution within nuclei. Long-term goals include analyses of regulation of receptor synthesis in target and nontarget tissues, of receptor evolution, and of gene regulatory sites. The principles of JH action as determined for the grasshopper should be equally valid for other insects, and additional knowledge of JH action may allow design of chemicals that target the insect hormone pathway to control populations with no harm to vertebrates.
