A digestive phospholipase A2 in larval mosquitoes, Aedes aegypti
Autor(es): Aliza, ARN; Stanley, DW
Resumo: We report on the presence of phospholipase A(2) activity in whole larva and midguts of the yellow fever mosquito Aedes aegypti. Phospholipase A(2) is responsible for hydrolyzing fatty acids from the sn-2 position of dietary phospholipids to release essential fatty acids for normal larval and adult growth. In contrast to the mammalian digestive phospholipase A(2) background, the Ae. aegypti phospholipase A(2) was Ca2+-independent. We further characterized the mosquito midgut phospholipase A(2) by altering the reaction conditions including incubation time, protein concentrations, pH and temperature. The site-specific PLA(2) inhibitor oleyloxyethylphosphorylcholine failed to inhibit the enzyme at concentrations up to 5000 mu M. We found that the phospholipase A(2) activity was consistently high throughout the fourth instar, but fell to very low levels on the first day of pupation which is a non-feeding stage. The enzyme is regulated with respect to feeding activity because fasting and re-feeding modified the larval digestive PLA(2) activity. (C) 1998 Elsevier Science Ltd. All rights reserved.
Palavras-Chave: Mosquito; Aedes aegypti; Polyunsaturated fatty acids (PUFAs); Phospholipid (PL); Phospholipase A2 (PLA2); Insect digesti
Imprenta: Insect Biochemistry and Molecular Biology, v. 28, n. 8, p. 561-569, 1998
Identificador do objeto digital: 10.1016/S0965-1748(98)00050-2
Descritores: Aedes aegypti - Biosynthesis
Data de publicação: 1998
