Stewart L M, Hirst M, López Ferber M, Merryweather A T, Cayley P J, Possee R D
NERC Institute of Virology and Environmental Microbiology, Oxford, UK.
Nature. 1991 Jul 4;352(6330):85-8. doi: 10.1038/352085a0.
Baculoviruses provide alternatives to chemicals for controlling insect pests and can be applied by spraying. Baculoviruses have a limited host range, but work relatively slowly. They are dissolved in the midgut of insect larvae to release infectious virions which enter gut epithelial cells and begin to replicate. Replication in other organs causes extensive tissue damage and eventually death. This process can take 4-5 days, but in the field may last for more than a week, allowing the larvae to feed for longer and thereby damaging the host plant. Baculovirus expression vectors expressing foreign genes, such as those for insect-specific toxins, hormones or enzymes, might alleviate this problem. We have now constructed a recombinant baculovirus derived from Autographa californica nuclear polyhedrosis virus containing an insect-specific neurotoxin from the venom of the North African (Algerian) scorpion, Androctonus australis Hector. The neurotoxin acts by causing specific modifications to the Na+ conductance of neurons, producing a presynaptic excitatory effect leading to paralysis and death; it has no effect in mice. Expression of the neurotoxin by the virus causes a reduction in the time required to kill the host insect.
杆状病毒为控制害虫提供了化学药剂之外的选择，可通过喷雾进行施用。杆状病毒的宿主范围有限，但起效相对较慢。它们在昆虫幼虫的中肠中溶解，释放出感染性病毒粒子，这些粒子进入肠道上皮细胞并开始复制。在其他器官中的复制会导致广泛的组织损伤并最终导致死亡。这个过程可能需要4至5天，但在田间可能会持续超过一周，使幼虫能够进食更长时间，从而损害宿主植物。表达外源基因（如昆虫特异性毒素、激素或酶的基因）的杆状病毒表达载体可能会缓解这个问题。我们现已构建了一种源自苜蓿银纹夜蛾核型多角体病毒的重组杆状病毒，其含有来自北非（阿尔及利亚）蝎子黄肥尾蝎毒液中的一种昆虫特异性神经毒素。该神经毒素通过对神经元的钠离子电导进行特定修饰而起作用，产生突触前兴奋效应，导致麻痹和死亡；它对小鼠没有影响。病毒表达这种神经毒素会缩短杀死宿主昆虫所需的时间。
