Tomalski M D, Miller L K
Department of Entomology, University of Georgia, Athens 30602.
Nature. 1991 Jul 4;352(6330):82-5. doi: 10.1038/352082a0.
Female mites of the species Pyemotes tritici inject an extremely potent venom into their insect prey that causes muscle-contraction and paralysis. These mites are able to paralyse insects 150,000 times their size and their venom is effective in a broad range of insect species. A toxin (TxP-I) associated with the mite venom apparatus causes immediate muscle-contractive paralysis when injected into insects but not mice. In this report, we describe the cloning, sequencing and expression of a complementary DNA (Tox-34) encoding TxP-I. Insect cells infected with a recombinant baculovirus (vEV-Tox34) expressing Tox-34 secrete three polypeptides related to TxP-I which cause paralysis on injection. Larvae infected with vEV-Tox34 become paralysed during infection, thus reflecting the potential application of this toxin gene in insect biocontrol methods. The toxin gene expression system will also allow further exploration of the neurophysiological basis of its insect-specific effects.
小麦嗜卷叶螨的雌螨会向其昆虫猎物注入一种极强的毒液，这种毒液会导致肌肉收缩和麻痹。这些螨虫能够麻痹比自身大15万倍的昆虫，而且它们的毒液对多种昆虫都有效。一种与螨毒液器官相关的毒素（TxP-I）注入昆虫体内时会立即导致肌肉收缩性麻痹，但注入小鼠体内则不会。在本报告中，我们描述了编码TxP-I的互补DNA（Tox-34）的克隆、测序和表达。感染了表达Tox-34的重组杆状病毒（vEV-Tox34）的昆虫细胞会分泌三种与TxP-I相关的多肽，这些多肽注入后会导致麻痹。感染vEV-Tox34的幼虫在感染过程中会麻痹，这反映了该毒素基因在昆虫生物防治方法中的潜在应用。该毒素基因表达系统还将有助于进一步探索其昆虫特异性作用的神经生理学基础。
