大豆叶毒蛾核型多角体病毒(Oa NPV)的超微结构及形态发生

THE ULTRASTRUCTURE AND MORPHOGENESIS OF A STRAIN OF NUCLEAR POYHEDROSIS VIRUS (OaNPV) ISOLATED FROM ORGYIA ANTIQUA (L.)

1987年,在哈尔滨从大豆叶毒蛾Orgyia antiqua(L.)感病致死幼体中分离出核型多角体病毒OaNPV一株。该病毒多角体近圆形,大小约0.4～2.1μm。多角体表面不光滑,有厚约9.0nm的多角体膜。多角体蛋白晶格为线型,晶格均宽约2.66 nm,晶格间距约1.66 nm,两个方向的平行线交角分别为53°和90°。病毒粒子为杆状,大小约62 nm×352 nm。大部分病毒粒子为单粒包埋,但观察到包含2粒和3粒核衣壳的病毒束,病毒粒子外膜为两层膜结构,厚约8.3 nm,内膜厚约2.2 nm。髓核呈螺旋形外观。病毒感染的脂肪体细胞的早期病理变化表现为:核仁消失,染色质凝集,随后细胞核中出现病毒发生基质和核衣壳。核衣壳获得外膜后,被封闭在多角体内。先形成的多角体多在细胞核的外围,多角体数量不断增加,最后充满整个细胞核。

<ABSTRACT> A strain of nuclear polyhedrosis virus (OaNPV) was isolated from a naturally deadlarva of rusty tussock moth Orgyia antiqua (L.) in Harbin. The polyhedra were nearlyround, ranging from 0.4μm to 2.1μm in diameter. There was a layer of about 9.0 nm--thickpolyhedral menbrane surrounding the polyhedra. The surface of polyhedra appeared unevenand wrinkly. Protein lattices of polyhedra belong to linear type. The lattice width and interdistance were about 2.66 nm and 1.66 nm respectively. The angles of intersection of two--di-rection parallel lines were 53°and 90°respectively. Rod-shaped virions were about 62 nm×352 nm in dimension approximately. There were virus bundles containing two and threenucleocapsids, but the majority of virions contained only one nucleocapsid within cach viralenvelope. The outer membrane with two--layer structure and inner membrane of virionswere about 8.3 nm and 2.2 nm in thickness respectively. The core appeared spiral in shape. An early sign of fat body cells infected with OaNOV was nucleus disappearance andchromatin coacervation. Then virogenic stroma and nucleocapsids were observed within thenucleus. After nucleocapsids acquired the outer menbrane, they were occluded intopolyhedra. The polyhedra formed earlier were mostly around the nucleus. Polyhedra in-creased progressively and finally filled the nucleus.