1 ISSN 0022-0930, Journal of Evolutionary Biochemistry and Physiology, 2013, Vol. 49, No. 1, pp. 1—9. © Pleiades Publishing, Ltd., 2013. Original Russian Text © R.A. Ilyasov, L.R. Gaifullina, E.S. Saltykova, A.V. Poskryakov, A.G. Nikolaenko, 2012, published in Zhurnal Evolyutsionnoi Biokhimii i Fiziologii, 2012, Vol. 48, No. 5, pp. 425—432. REVIEWS Defensins in the Honeybee Antiinfectious Protection R. A. Ilyasov, L. R. Gaifullina, E. S. Saltykova, A. V. Poskryakov, and A. G. Nikolaenko Institute of Biochemistry and Genetics, Ufa Research Center, Russian Academy of Sciences, Ufa, Bashkortostan, Russia E-mail: apismell@hotmail.com Received 10 October, 2011 Abstract—Specific conditions of the honeybee life honeybee life require the presence of effective mechanisms of antiinfectious protection whose one of the most important components are defensins—the family of antimicrobial peptides. In the honeybee, defensins are present in the form of two different peptides—defensin 1 and 2 that are similar between each other only by 55.8%. Defensin 1 synthesized in salivary glands plays an important role in social immunity, whereas defensin 2 synthesized by cells of fat body and lymph is an important factor in the system of the honeybee individual immunity. Defensins are inducible, are controlled by interaction of Toll and Imd signal pathways and have a large specter of antimicrobial action. DOI: 10.1134/S0022093013010015 Key words: honeybee, Apis mellifera, antimicrobial peptides defensins, evolution, immunity. tant components of the honeybee immune system [3]. This is one of the evolutionary ancient and important mechanisms of invertebrates. AMP can be activated for the short time interval and be de- livered to the site of infection [8]. By the strength of their action, AMP are compared with antibi- otics and can be used for the elaboration of the medications that have antifungal and antibacterial properties [9]. The use of the antifungal prepara- tions and antibiotics at treatment of honeybee dis- eases leads to suppression of their own immunity, to the appearance of pathogens stable to them, and to pollution of products of apiculture. Thus, T. Miyagi with coauthors (2000) [10] showed development of resistance of the pathogenic for honeybees bacteria of the American foulbrood Paenibacillus larvae larvae to the antibiotic oxytet- racycline. Solution of this problem is an enhance- ment of the honeybee immunity by an increase in the AMP expression level AMP in the honeybees themselves [11]. Unfortunately, data on study of defensins that have the greatest polymorphism INTRODUCTION The family of honeybee Apis mellifera mellifera L. is represented by more than 10 thousand in- dividuals in the limited space of the hive. The constant temperature of 37°C inside the hive and frequent contacts of individuals created the ideal medium for fast spreading of infectious diseases [1]. These life conditions promoted the appear- ance of different mechanisms of antiinfectious protection. Apart from the individual protection systems, the collective mechanisms of resistance were developed in social insects in the process of evolution to compensate the increased risk of in- fection by the pathogenic microorganisms in the common life style. These protective mechanisms were called “social”, “public” or “collective im- munity” [2]. The components of the honeybee humoral antiinfectious protection are expressed in hemolymph [3], fat body [4], and cuticle [5], in middle intestine [6] and in salivary glands [7]. The antimicrobial peptides (AMP) are impor-