title: Plasmodium yoelii: semiquantitative analyses of circumsporozoite protein gene expression during the sporogonic development of P. y. yoelii and P. y. nigeriensis in the mosquito vector Anopheles stephensi.
abstract: Malaria infection in the mosquito vector can be modulated by the vertebrate host, mosquito factors, and interactions between different parasite populations. Modulation of parasite development can be assessed through the study of gene expression. The present report describes a specific, sensitive, and nonradioactive method that permits assessment of parasite load and quantification of circumsporozoite protein gene expression during the sporogonic stages of Plasmodium yoelii yoelii and P. y. nigeriensis. A decrease in parasite load was observed when comparing DNA of oocysts on day 7 postinfection with that of oocysts and sporozoites on day 19. On day 7, parasites (oocysts) showed a marked increase of circumsporozoite protein expression when compared with that (sporozoites and oocysts) on day 19. The method developed in this work can be a valuable tool to understand parasite interaction mechanisms that are involved in mosquito malaria infections.
authors.affiliation: Centro de Malária e Outras Doenças Tropicais e Unidade de Ensino e Investigação da Malaria, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa, 1349-008 Lisboa, Portugal.
authors.forename: Ana S
authors.initials: AS
authors.lastname: Franco
authors.forename: Henrique
authors.initials: H
authors.lastname: Silveira
authors.forename: Virgílio E
authors.initials: VE
authors.lastname: do Rosário
mesh_terms: D000818:Animals; D000852:Anopheles / Q000469:parasitology*; D017931:DNA Primers; D015342:DNA Probes; D018076:DNA, Complementary / Q000032:analysis; D016054:DNA, Protozoan / Q000032:analysis; D005260:Female; D018507:Gene Expression Regulation, Developmental; D007303:Insect Vectors / Q000469:parasitology*; D051379:Mice; D010967:Plasmodium yoelii / Q000235:genetics* / Q000254:growth & development; D015800:Protozoan Proteins / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics
chemical_list: D017931:DNA Primers; D015342:DNA Probes; D018076:DNA, Complementary; D016054:DNA, Protozoan; D015800:Protozoan Proteins; C041595:circumsporozoite protein, Protozoan; D013762:Tetrahydrofolate Dehydrogenase