Autor(es): Pierro, Dennis J.; Powers, Erik L.; Olson, Ken E.

Resumo: Mosquito midgut epithelial cells (MEC) play a major role in determining whether an arbovirus can successfully infect and be transmitted by mosquitoes. The Sindbis virus (SINV) strain TR339 efficiently infects Aedes aegypti MEC but the SINV strain TE/52J poorly infects MEC. SINV determinants for MEC infection have been localized to the E2 glycoprotein. The E2 amino acid sequences of TR339 and TE/52J differ at two sites, E2-55 and E2-70. We have altered the TE/52J virus genome by site-directed mutagenesis to contain two TR339 residues, E2-55 H->Q (histidine to glutamine) and E2-70 K->E (lysine to glutamic acid). We have characterized the growth patterns of derived viruses in cell culture and determined the midgut infection rate (MIR) in A. aegypti mosquitoes. Our results clearly show that the E2-55 H->Q and the E2-70 K->E mutations in the TE/52J virus increase MIR both independently and in combination. TE/52J virus containing both TR339 E2 residues had MIRs similar to the parental TR339 virus. In addition, SINV propagated in a mammalian cell line had a significantly lower A. aegypti midgut 50 % infectious dose than virus propagated in a mosquito cell line.

Palavras-Chave: Viral diseases; Mutations; Cell culture; Glycoproteins; Mutagenesis; Site-directed mutagenesis; Epithelial cells; Glutamine; Lysine; Infection; Growth patterns; Mammalian cells; Histidine; Glutamic acid; Mutation

Imprenta: Journal of General Virology, v. 88, n. 5, p. 1545-1554, 2007.

Descritores: Aedes aegypti - Biochemistry ; Aedes aegypti - Cell ; Aedes aegypti - Infectious diseases ; Aedes aegypti - Viral infections ; Aedes aegypti - Virus ; Aedes aegypti - Immunology ; Aedes aegypti - Public health

Data de publicação: 2007