Knockdown of the Rhipicephalus microplus Cytochrome c Oxidase Subunit III Gene Is Associated with a Failure of Anaplasma marginale Transmission

Author(s)

Bifano, Thais D. ^{[1, 2]} ; Ueti, Massaro W. ^[3] ; Esteves, Eliane ^[1] ; Reif, Kathryn E. ^[2] ; Braz, Gloria R. C. ^{[4, 5]} ; Scoles, Glen A. ^[3] ; Bastos, Reginaldo G. ^[2] ; White, Stephen N. ^[3] ; Daffre, Sirlei ^{[1, 4]}

Affiliation

^[1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Parasitol, BR-05508 Sao Paulo - Brazil

^[2] Washington State Univ, Dept Vet Microbiol & Pathol, Pullman, WA 99164 - USA

^[3] Washington State Univ, USDA ARS, Anim Dis Res Unit, Pullman, WA 99164 - USA

^[4] Inst Nacl Ciencia & Tecnol Entomol Mol, Rio De Janeiro, RJ - Brazil

^[5] Univ Fed Rio de Janeiro, Inst Quim, Dept Biochem, Rio De Janeiro, RJ - Brazil

• Document type: Journal article
• Source: PLoS One; v. 9, n. 5 MAY 30 2014.
• Web of Science Citations: 6

Abstract

Rhipicephalus microplus is an obligate hematophagous ectoparasite of cattle and an important biological vector of Anaplasma marginale in tropical and subtropical regions. The primary determinants for A. marginale transmission are infection of the tick gut, followed by infection of salivary glands. Transmission of A. marginale to cattle occurs via infected saliva delivered during tick feeding. Interference in colonization of either the tick gut or salivary glands can affect transmission of A. marginale to naive animals. In this study, we used the tick embryonic cell line BME26 to identify genes that are modulated in response to A. marginale infection. Suppression-subtractive hybridization libraries (SSH) were constructed, and five up-regulated genes [glutathione S-transferase (GST), cytochrome c oxidase sub III (COXIII), dynein (DYN), synaptobrevin (SYN) and phosphatidylinositol-3,4,5-triphosphate 3-phosphatase (PHOS)] were selected as targets for functional in vivo genomic analysis. RNA interference (RNAi) was used to determine the effect of tick gene knockdown on A. marginale acquisition and transmission. Although RNAi consistently knocked down all individually examined tick genes in infected tick guts and salivary glands, only the group of ticks injected with dsCOXIII failed to transmit A. marginale to naive calves. To our knowledge, this is the first report demonstrating that RNAi of a tick gene is associated with a failure of A. marginale transmission. (AU)

• FAPESP's process: 11/22124-8 - Functional genomics analysis of the interaction between Rhipicephalus (Boophilus) microplus and Anaplasma marginale
• Grantee: Thaís Duarte Bifano
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor