The intact 741 hp polyhedrin gene of LsNPV was sequenced by Silver Sequencing System, and shares 90.6% and 97.0% nucleotide identity, 97.2% and 97. 6% amino acid identity with PfNPV and MdNPV polh genes respectively....The intact 741 hp polyhedrin gene of LsNPV was sequenced by Silver Sequencing System, and shares 90.6% and 97.0% nucleotide identity, 97.2% and 97. 6% amino acid identity with PfNPV and MdNPV polh genes respectively. The 14 hp conservative sequence with the core element GTAAG,is located in the 5'untranslated region of the gene. The polh gene was predicted to encodes a 246 amino sold residures with molecular weight of 29.0 kd, in which the number of acidic amino acids and alkaline amino acids was roughly equal resulting in almost no charges in polyhedrin protein molecule and hence occlusion body. It gives a valuable implication that ionic bonds as well as hydrophobic bonds and hydrogen bond may Play an important role in the crystallization or polyhedrin, by comparing amino acid variation of twenty-one polyhedrin. The comparison of promoter regions of polyhedrin gene and class Ⅲ gene shown that they are very similar, but also have differences in GC content.This could explain that both categories of gene are highly expressed, and polyhedrin genes are expressed more higher than class Ⅲ gene.展开更多
The green fluorescence of bioluminescent jellyfish Aequorea victoria is due to the presence of the green fluorescent protein (GFP). To examine whether the GFP gene can be applied as a reporter gene in insect cells...The green fluorescence of bioluminescent jellyfish Aequorea victoria is due to the presence of the green fluorescent protein (GFP). To examine whether the GFP gene can be applied as a reporter gene in insect cells, a baculovirus transfer vector containing the neomycin resistance gene (neo) was established. The GFP gene was subcloned into the vector downstream of the polyhedrin gene (ocu) promoter. In the presence of G418, the recombinant virus can be purified. Expression of the GFP gene in the recombinant virus should give rise to synthesis of the GFP with a molecular weight of 30×10 3 dalton, and is observable by the strong green light irradiated by ultraviolet or blue light in viable intact insect cells. The GFP produced in insect cells has typical fluorescent spectra indistinguishable from those of the purified native GFP. The GFP gene as a good reporter gene can be applied to the baculovirus insect cell expression system.展开更多
LdMNPV-NEFU isolate collected from the forestry farm of Northeast Forestry University was purified and the genomic DNA of LdMNPV was extracted. The LdMNPV polyhedrin gene was cloned by PCR. The results showed that the...LdMNPV-NEFU isolate collected from the forestry farm of Northeast Forestry University was purified and the genomic DNA of LdMNPV was extracted. The LdMNPV polyhedrin gene was cloned by PCR. The results showed that the sequence was an open reading frame (ORF) of 735bp capable of encoding 245 amino acids. The polyhedrin gene sequences of the LdMNPV-NEFU isolate and a Canada strain, LdMNPV-G differed in 5 bases. The polyhedrin gene of the LdMNPV-NEFU isolate contained C, G, T, C and G at 54, 109,379, 508 and 701 sites from the start codon, but the LdMNPV-G isolate contained G, C, C, T and T at the corresponding sites respectively. The same amino acids were encoded by the two ORF sequences, with the exception that Asp and His are encoded by GAC on the polyhedrin gene sequence of the LdMNPV-NEFU isolate and by CAC in the LdMNPV-G isolate. The LdMNPV polyhedrin gene was expressed in E.coli BL21 (DE3) by the pT7-7 plasmid vector.展开更多
The polyhedrin gene of EpNPV was located on Hin d III E, Xba I B, Eco RI J, Kpn I A, Pst I F, Bam H I G fragments under stringent condition(68℃,in water),by using the DIG labeled Bam H I F fragment of AcMNPV DNA as t...The polyhedrin gene of EpNPV was located on Hin d III E, Xba I B, Eco RI J, Kpn I A, Pst I F, Bam H I G fragments under stringent condition(68℃,in water),by using the DIG labeled Bam H I F fragment of AcMNPV DNA as the probe.In order to sequence the EpNPV polyhedrin gene,the Bam H I G fragment was cloned into pTZ19R vector.Then the fragment was digested by Xba I? Hin d III,and subcloned into pTZ19R.展开更多
文摘The intact 741 hp polyhedrin gene of LsNPV was sequenced by Silver Sequencing System, and shares 90.6% and 97.0% nucleotide identity, 97.2% and 97. 6% amino acid identity with PfNPV and MdNPV polh genes respectively. The 14 hp conservative sequence with the core element GTAAG,is located in the 5'untranslated region of the gene. The polh gene was predicted to encodes a 246 amino sold residures with molecular weight of 29.0 kd, in which the number of acidic amino acids and alkaline amino acids was roughly equal resulting in almost no charges in polyhedrin protein molecule and hence occlusion body. It gives a valuable implication that ionic bonds as well as hydrophobic bonds and hydrogen bond may Play an important role in the crystallization or polyhedrin, by comparing amino acid variation of twenty-one polyhedrin. The comparison of promoter regions of polyhedrin gene and class Ⅲ gene shown that they are very similar, but also have differences in GC content.This could explain that both categories of gene are highly expressed, and polyhedrin genes are expressed more higher than class Ⅲ gene.
文摘The green fluorescence of bioluminescent jellyfish Aequorea victoria is due to the presence of the green fluorescent protein (GFP). To examine whether the GFP gene can be applied as a reporter gene in insect cells, a baculovirus transfer vector containing the neomycin resistance gene (neo) was established. The GFP gene was subcloned into the vector downstream of the polyhedrin gene (ocu) promoter. In the presence of G418, the recombinant virus can be purified. Expression of the GFP gene in the recombinant virus should give rise to synthesis of the GFP with a molecular weight of 30×10 3 dalton, and is observable by the strong green light irradiated by ultraviolet or blue light in viable intact insect cells. The GFP produced in insect cells has typical fluorescent spectra indistinguishable from those of the purified native GFP. The GFP gene as a good reporter gene can be applied to the baculovirus insect cell expression system.
文摘LdMNPV-NEFU isolate collected from the forestry farm of Northeast Forestry University was purified and the genomic DNA of LdMNPV was extracted. The LdMNPV polyhedrin gene was cloned by PCR. The results showed that the sequence was an open reading frame (ORF) of 735bp capable of encoding 245 amino acids. The polyhedrin gene sequences of the LdMNPV-NEFU isolate and a Canada strain, LdMNPV-G differed in 5 bases. The polyhedrin gene of the LdMNPV-NEFU isolate contained C, G, T, C and G at 54, 109,379, 508 and 701 sites from the start codon, but the LdMNPV-G isolate contained G, C, C, T and T at the corresponding sites respectively. The same amino acids were encoded by the two ORF sequences, with the exception that Asp and His are encoded by GAC on the polyhedrin gene sequence of the LdMNPV-NEFU isolate and by CAC in the LdMNPV-G isolate. The LdMNPV polyhedrin gene was expressed in E.coli BL21 (DE3) by the pT7-7 plasmid vector.
文摘The polyhedrin gene of EpNPV was located on Hin d III E, Xba I B, Eco RI J, Kpn I A, Pst I F, Bam H I G fragments under stringent condition(68℃,in water),by using the DIG labeled Bam H I F fragment of AcMNPV DNA as the probe.In order to sequence the EpNPV polyhedrin gene,the Bam H I G fragment was cloned into pTZ19R vector.Then the fragment was digested by Xba I? Hin d III,and subcloned into pTZ19R.
