title: RNA interference of cytosolic leucine aminopeptidase reduces fecundity in the hard tick, Haemaphysalis longicornis.
abstract: Ticks are effective vectors of pathogens because of their blood feeding and high fecundity. This high fecundity is related to the size of the blood meal. Therefore, knowledge of how blood proteins are degraded and converted to proteins, including yolk protein, is important for the development of ways to inhibit the utilization of blood proteins by ticks. RNA interference (RNAi) is becoming a powerful post-transcriptional gene silencing technique that provides insight into gene function. We constructed a double-stranded RNA (dsRNA) based on a previously cloned Haemaphysalis longicornis leucine aminopeptidase (HlLAP) gene to reevaluate the biological role in tick blood digestion. Gene specific transcriptional, translational, and functional disruptions were achieved by the introduction of dsRNA into the ticks. Significantly delayed onset of egg-laying and reduced egg oviposition resulted from the RNAi for the HlLAP gene. These results suggest that HlLAP actually works as a blood digestive enzyme and affects tick fecundity via unknown mechanisms. The reduction of egg oviposition may be caused by a decrease in nutrients, especially free amino acids generated by HlLAP, from the blood meal. This is the first report of an impact on tick reproduction caused by gene silencing of a blood digestion-related molecule.
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hatta
authors.forename: Rika
authors.initials: R
authors.lastname: Umemiya
authors.forename: Min
authors.initials: M
authors.lastname: Liao
authors.forename: Haiyan
authors.initials: H
authors.lastname: Gong
authors.forename: Thasaneeya
authors.initials: T
authors.lastname: Harnnoi
authors.forename: Miho
authors.initials: M
authors.lastname: Tanaka
authors.forename: Takeharu
authors.initials: T
authors.lastname: Miyoshi
authors.forename: Damdinsuren
authors.initials: D
authors.lastname: Boldbaatar
authors.forename: Badgar
authors.initials: B
authors.lastname: Battsetseg
authors.forename: Jinlin
authors.initials: J
authors.lastname: Zhou
authors.forename: Xuenan
authors.initials: X
authors.lastname: Xuan
authors.forename: Naotoshi
authors.initials: N
authors.lastname: Tsuji
authors.forename: Demar
authors.initials: D
authors.lastname: Taylor
authors.forename: Kozo
authors.initials: K
authors.lastname: Fujisaki
mesh_terms: D000818:Animals; D003600:Cytosol / Q000201:enzymology; D005247:Feeding Behavior; D005298:Fertility / Q000235:genetics*; D005786:Gene Expression Regulation; D026863:Ixodidae / Q000201:enzymology*; D007931:Leucyl Aminopeptidase / Q000235:genetics* / Q000378:metabolism; D010058:Oviposition; D034622:RNA Interference
chemical_list: D007931:Leucyl Aminopeptidase