【摘要】 中红侧沟茧蜂Microplitismediator雌蜂输卵管萼中有一种病毒样纤丝 (virus likefilaments ,VLFs)。在蜂卵从卵巢管通过输卵管萼产出的过程中 ,VLF包裹在蜂卵的表面 ,随蜂卵进入寄主体内。透射电镜显示 ,VLF中心是电子致密物质 ,外有单层膜包被 ,直径约 35nm。负染技术表明 ,VLF是具有左螺旋结构的纤丝 ,负染时的直径约 2 5nm。不含VLF的蜂卵进入 3龄初寄主后 ,全部被寄主血细胞包囊 ;含有VLF的蜂卵进入同样的寄主后 ,88 2 %受到保护。VLF对蜂卵的保护作用在不同发育期的寄主中不同 ,在 3龄初的粘虫体内 ,平均有 64 7%的初产卵不被包囊 ,而在 4龄初的粘虫体内 ,只有 9 5%的初产卵受到保护。这一结果说明 ,VLF只能为蜂卵提供部分的保护作用 ,需配合其它寄生蜂因子 (萼液、蜂毒等 )共同作用于寄主的免疫系统更多还原

【Abstract】 There were virus like filaments (VLFs) in the calyx regions of oviduct in the female wasp, Microplitis mediator Haliday. When an egg passed through the calyx region, the VLF attached to its surface and entered into the hemocoel of the host along with the egg. Transmission electron microscopy showed that an electron dense core of 35 nm in diameter was wrapped by one layer membrane in the center of the VLF. The VLF exhibited a very long levogyrate structure with a diameter of 25 nm under negative staining. All of the wasp’s eggs without VLFs were encapsulated in the hosts, early 3rd instar larvae of Mythimna separata while 88 2% of eggs were protected from encapsulation when they were covered by VLFs in the same host. The ability of VLF in protecting the wasp’s eggs from encapsulation was different in the hosts at different stages. 64 7% and 9 5% newly laid eggs was unencapsulated in the early 3rd and 4th instar host larvae respectively. These results suggested that the VLF only provided partial protection for the wasp’s eggs and other factors (calyx fluid and venom, etc.) should make certain contribution to the immune system of the host, too.更多还原