Archives of Insect Biochemistry and Physiology 55:55–67 (2004) © 2004 Wiley-Liss, Inc. DOI: 10.1002/arch.10123 Published online in Wiley InterScience (www.interscience.wiley.com) The Effect of Mutations Altering Biogenic Amine Metabolism in Drosophila on Viability and the Response to Environmental Stresses N. Gruntenko, 1 * N.A. Chentsova, 1 E.V. Bogomolova, 1 E.K. Karpova, 1 G.V. Glazko, 1 N.V. Faddeeva, 1 M. Monastirioti, 2 and I. Yu. Rauschenbach 1 Dopamine (DA) content, tyrosine decarboxylase (TDC) activity and survival were studied under normal and environmental stress conditions in the ste and e strains carrying ebony mutation increasing DA level and the octopamineless strain Tbh nM18 of Drosophila melanogaster. Wild-type strains Canton S and Oregon R, and strain p845 from which Tbh nM18 strain was derived were used as controls. Sexual dimorphism of TDC activity, DA content, and survival in flies of all D. melanogaster strains under study was found. Tbh nM18 mutation sharply reduced TDC activity in females, while ebony had no such effect. DA content and survival under heat stress in Tbh nM18 flies did not differ from those in the wild type. ste and e flies had drastically increased DA content under normal conditions, dramatically decreased survival under heat stress, but increased survival under starva- tion. DA content and survival under heat stress were also studied in the reciprocal hybrids (males) F 1 of the cross D. virilis strains 101 (wild type) and 147 with X-linked mutation, which significantly increases DA content. 147´101 males had a considerably higher DA content and lower survival than 101´147 ones. Individuals of all D. melanogaster strains under study developed the stress reaction, as judged by changes in TDC activity and DA levels. The role of biogenic amines in the stress reaction development and adaptation to environmental stresses in Drosophila is discussed. Arch. Insect Biochem. Physiol. 55:55–67, 2004. © 2004 Wiley-Liss, Inc. KEYWORDS: Drosophila; heat stress; tyrosine decarboxylase; dopamine; viability INTRODUCTION It is well known that biogenic amines play an important role in the regulation of insects’ energy metabolism: octopamine (OA) and dopamine (DA) control the conversion of glycogen to treha- lose and its release into the hemolymph, stimu- late oxidation of glucose and trehalose, as well as lipids release from the fat body; and OA injection increases the levels of sugars and lipids (Candy, 1979; Downer, 1979; Orchard et al., 1982; Wood- ring et al., 1989). It has been shown that unfavorable conditions cause an increase in the content of OA and DA in insects of various species. This response to stressor is non-specific, i.e., it arises under the action of stressors of different origins: high and low tem- perature, mechanical and chemical stimuli, high population density, and also under immobilization conditions (Orchard and Loughton, 1981; Daven- 1 Institute of Cytology and Genetics, Siberian Division of Russian Academy of Sciences, Novosibirsk, Russia 2 Institute of Molecular Biology and Biotechnology, Heraklion, Crete, Greece *Correspondence to: N.E. Gruntenko, ICG SD RAS, Lavrentieva ave #10, Novosibirsk 630090, Russia. E-mail: nataly@bionet.nsc.ru Contract grant sponsor: Russian Foundation for Basic Research; Contract grant number: 03-04-48168; Contract grant sponsor: Integration Project of Siberian Division of Russian Academy of Sciences; Contract grant number: 151; Contract grant sponsor: President of Russian Federation; Contract grant sponsor: Siberian Division of Russian Academy of Sciences. Received 1 March 2002; Accepted 12 August 2003