Identification and transcriptional profile of Culex quinquefasciatus Say (Diptera: Culicidae) lipophorin in different stages.

Lipophorin is a major hemolymph lipoprotein found in insects with a molecular native mass of 700 kDa. In mosquitoes, two different types of apolipoproteins are characterized, apolipophorin-I (ApoLp-I, ~250 kDa) and apolipophorin-II (ApoLp-II, ~80 kDa). This concentration depends on the stage of development and the age of the insects. Lipophorins are best studied in mosquitoes of the genus Aedes and Anopheles. In this study, we analyze the lipophorin sequence and show the lipophorin purification of the Culex quinquefasciatus and the transcriptional profile of the lipophorin gene in different life cycle stages. Similar amino acid composition and molecular weights are founded in three mosquitoes species lipophorins amino acid sequence. The two subunits of purified lipophorin (Apo I and Apo II) showed molecular masses of approximately 248 and 93 kDa, like that found in other mosquitoes. A gradual increase in the lipophorin expression gene was obtained during the previtellogenic period and after feeding we obtained peak expression at 24 h after feeding. With our results, we conclude that C. quinquefasciatus protein sequence has the same characteristics as those observed in other mosquitoes and that the expression of its apolipophorins is induced by blood feeding.

The First Molecular Characterization of Anopheles (Nyssorhynchus) aquasalis (Diptera: Culicidae) Vitellogenin Expression Products and a Partial cDNA Sequence Isolation.

Anopheles (Nyssorhynchus) aquasalis Curry, 1932, is an anopheline that plays an important role in Plasmodium transmission in the New World. Few studies have explored the molecular reproductive biology of this vector species. In the current study, we isolated and sequenced a partial, 886 bp, cDNA fragment of a vitellogenin (Vtg) gene from An. aquasalis. The transcription profile of this Vtg gene in adult females was characterized, and it is similar to other members of the Culicidae. We also detected a smaller subunit of An. aquasalis Vtg proteins in ovary tissue and characterized its translational profile in previtellogenic and vitellogenic females. Our results represent the first molecular characterization of An. aquasalis vitellogenin expression products.