Multiplication of NPV and expression of polyhedrin gene in the midgut epithelium of silkworm, Bombyx mori

• Published in: Nihon sanshigaku zasshi Vol. 68; no. 1; pp. 19 - 25
• Main Authors: Tsuda, H. (Shinshu Univ., Ueda, Nagano (Japan). Faculty of Textile Science), Nakagaki, M, Hashimoto, T, Kajiura, Z, Takei, R, Iwashita, Y
• Format: Journal Article
• Language: Japanese; English
• Published: The Japanese Society of Sericultural Science 1999
• Subjects: BOMBYX MORI; ENFERMEDADES DE LOS INSECTOS; EXPRESION GENICA; EXPRESSION DES GENES; GENE EXPRESSION; INSECT DISEASES; MALADIE DES INSECTES; midgut epithelial cell; NPV; NUCLEAR POLYHEDROSIS VIRUS; polyhedron formation; VIRUS POLIEDROSIS NUCLEAR; VIRUS POLYEDROSE NUCLEAIRE
• ISSN: 0037-2455; 1884-796X
• DOI: 10.11416/kontyushigen1930.68.19

We determined the amounts of viral DNA, polyhedrin mRNA and polyhedrin in the midgut epithelial cells infected with BmNPV, in order to study the poor production of polyhedra in these cells. When the appearance and accumulation of polyhedrin mRNA in the midgut epithelial cells were investigated by northern blot analysis, polyhedrin mRNA were detected as early as 6 h post-infection (p. i.). At 12 h p. i., amount of polyhedrin mRNA increased in the midgut epithelial cells. Quantitative PCR of virus DNA in the midgut epithelial and fat body cells at 72 h p. i. indicated that amount of the virus DNA in midgut epithelial cells was close to that in fat body cells, suggesting that virus DNA synthesis occurred in midgut epithelial cells. Quantitative RT-PCR for polyhedrin mRNAs in the midgut epithelial and fat body cells at 72 h p. i. indicated that amounts of the mRNA in both cells did not differ significantly each other, suggesting that the transcription of polyhedrin gene occurred markedly in midgut epithelial cells. Western blot analysis showed that polyhedrin was produced in midgut epithelial cells, but its amount was much lower than that in fat body cells. It is concluded that low level of at translation of polyhedrin gene may be related to poor polyhedron formation in midgut epithelial cells