期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2004
卷号：101
期号：16
页码：5874-5879
DOI：10.1073/pnas.0307529101
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Most female ixodid ticks, once mated, feed to repletion within 6-10 days. Previous studies indicate that an engorgement factor (EF), passed to the female during copulation, may be the stimulus for engorgement. Here, we show that extracts of the testis/vas deferens of fed (but not unfed) male Amblyomma hebraeum contain EF bioactivity when injected into the hemocoel of feeding virgins. We have produced recombinant proteins (recproteins) from 28 feeding-induced genes in the male gonad and have identified a recombinant A. hebraeum engorgement factor (recAhEF) among these recproteins. recAhEF is a combination of two peptides, recAhEF{alpha} (16.1 kDa) and recAhEF{beta} (11.6 kDa), neither of which has bioactivity on its own. recAhEF also stimulates salivary gland degeneration and partial development of the ovary, suggesting that it may be the same material as another male gonadal protein from this tick, male factor. We propose the name "voraxin" for the natural EF of ticks. When normal mated females were put on a rabbit immunized against recAhEF, 74% failed to feed beyond one-tenth the normal engorged weight within 14 days whereas all mated ticks put on a control rabbit engorged normally (mean duration of 8.8 {+/-} 0.8 days). This result constitutes preliminary evidence that an anti-tick vaccine might be developed from voraxin.
