Quantification of vitellogenesis and its control by 20-hydroxyecdysone in the ixodid tick, Amblyomma hebraeum

dc.contributor.authorFriesen, Kevin
dc.contributor.authorKaufman, Reuben
dc.date.accessioned2016-05-09
dc.date.accessioned2022-05-28T00:38:19Z
dc.date.available2022-05-28T00:38:19Z
dc.date.issued2002
dc.description.abstractOvaries of the ixodid tick, Amblyomma hebraeum Koch, grew rapidly after engorgment as a result of yolk uptake. At 26 °C, oviposition began by day 10 post-engorgement, plateaued on days 16–18, and ended by day 38. Vitellin (Vt) was partially purified from ovaries of day 10 engorged ticks by gel filtration and ion exchange chromatography. This Vt comprises seven major and several minor polypeptides. Two polypeptides (211 and 148 kD) from haemolymph of engorged female ticks corresponded to minor polypeptides of similar molecular weight in the ovary. The haemolymph titre of the 211 and 148 kD polypeptides increased up to the onset of oviposition. These polypeptides were absent in males and non-vitellogenic females (day 0 engorged or day 10 partially-fed females), and were thus designated as vitellogenin (Vg). Antibodies raised against haemolymph Vg211 and 148 recognized these polypeptides in partially purified Vt, as well as six of the seven major polypeptides. Using these antibodies we developed an indirect, competitive ELISA to quantify Vg. Rise in haemolymph Vg-concentration lagged slightly behind the rise in haemolymph ecdysteroid (ES)-concentration, and Vg-synthesis was stimulated by injections of 20E into non-vitellogenic females. These observations indicate that an ES is the vitellogenic hormone in A. hebraeum.
dc.description.urihttps://library.macewan.ca/cgi-bin/SFX/url.pl/8FP
dc.format.extenthttps://library.macewan.ca/cgi-bin/SFX/url.pl/8FP
dc.identifierhttps://doi.org/10.1016/S0022-1910(02)00107-5
dc.identifier.citationFriesen, K. J., & Kaufman, W. R. (2002). Quantification of vitellogenesis and its control by 20-hydroxyecdysone in the ixodid tick, Amblyomma hebraeum. Journal of Insect Physiology, 48(8), 773-782. doi:10.1016/S0022-1910(02)00107-5
dc.identifier.urihttps://hdl.handle.net/20.500.14078/1018
dc.languageEnglish
dc.language.isoen
dc.rightsAll Rights Reserved
dc.subjectixodid ticks
dc.subjectamblyomma
dc.subjectvitellogenesis
dc.subjectvitellogenin
dc.subject20-hydroxyecdysone
dc.titleQuantification of vitellogenesis and its control by 20-hydroxyecdysone in the ixodid tick, Amblyomma hebraeum
dc.typeArticle
dspace.entity.type
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