Comparação transcricional dos túbulos de Malpighi e corpo gorduroso de Zophobas morio: função de AMP-CoA ligases nos túbulos e relação com lanternas de Arachnocampa luminosa

Abstract

The Malpighian tubules in insects play an essential role in osmoregulation, performing transport of ions and fluids during the formation of primary urine, whereas fat body is usually associated with the intermediary metabolism. The tubules also are involved in excretion of organic solutes and xenobiotics, and in unusual functions such as bioluminescence in Diptera. However, with the exception of a preliminar transcriptional survey of the Zophobas morio larval tubules, there are no detailed transcriptional analysis of this organ in Coleoptera. A luciferase-like enzyme that displays weak luminescence activity in the presence of firefly D-luciferin was cloned from the tubules of Z. morio larvae. Therefore, to better understand the molecular physiology of tubules and fat body in Coleoptera and analyse the AMP-CoA ligases enzymes, we performed a comparative transcriptional analysis of these tissues from Z. morio. As expected, the tubules displayed organic and inorganic transporters, xenobiotic metabolism enzymes, V-ATPases, channels, and pumps. Fat body showed proteins that are synthesized in this tissue and secreted to the hemolymph, lipidic and carbohydrates metabolism enzymes. Although these tissues perform distinct physiological functions in insects, they are also involved in common pathways, such as nitrogen metabolism to degradation/excretion, eye pigments biosynthesis, immunity, and detoxification. Ours results corroborate to the physiological versatility of tubules and fat body in a Coleopteran larvae. Futhermore our analysis also indicates the presence of coumarate like-ligases isoforms that could be related to degradation of coumaric acids derivatives or biosynthesis of eye pigments.