Skip to content
Free planNo credit card requiredStart writing
AI for Research home
AI for Research home
Dashboard
Sign inGet started

Search 250 million research papers

Read the abstract, see who wrote it and who cites it, and get the citation in APA, MLA, Chicago or Harvard.

About 768 papers for “Polyhedrin”

Integration of Cypoviruses into polyhedrin matrix

Olga V. Konevtsova, Ivan Golushko, Rudolf Podgornik et al. · Nanoscale Advances · 2023

Unlike in other viruses, in Cypoviruses the genome is doubly protected since their icosahedral capsids are embedded into a perfect polyhedrin crystal. Current experimental methods cannot resolve the resulting interface structure and we propose a symmetry-based approach to predict it. We reveal a remarkable match between the surfaces of Cypovirus and the outer polyhedrin matrix. The match arises due to the preservation of the common tetragonal symmetry, allowing perfect contacts of polyhedrin trimers with VP1 and VP5 capsid proteins. We highlight a crucial role of the VP5 proteins in embedding the Cypovirus into the polyhedrin matrix and discuss the relationship between the nucleoside triphosphatase activity of the proteins and their role in the superstructure formation. Additionally, we propose an electrostatic mechanism that drives the viral superstructure disassembly occurring in the alkaline environment of the insect intestines. Our study may underpin novel strategies for engineering proteinaceous nanocontainers in diverse biotechnological and chemical applications.

Cited by 3Open access

AnCPV RNA dependent RNA polymerase and polyhedrin phylogeny.

Guillaume Carissimo (2636878), Karin Eiglmeier (8102), Julie Reveillaud (225126) et al. · Figshare · 2016

<p>(A) Neighbor-joining tree of RNA-dependent RNA polymerase (RdRp) sequences of Cypoviruses, (B) Neighbor-joining tree of polyhedrin sequences of Cypoviruses. Multiple protein alignment was performed with the longest ORF (corresponding to the polymerase) for each nucleic acid. NJ bootstrap values (above 0.75) are indicated above branches. Pairwise distances are indicated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0153881#pone.0153881.s010" target="_blank">S6 File</a>.</p>

Cited by 0Open access

Expression of CSFV E2 protein fused with partial polyhedrin.

Sung Min Bae (401039), Hee Jung Kim (401040), Jun Beom Lee (401041) et al. · Figshare · 2015

<p>Sf21 cells were infected at an MOI of 5 with each virus and harvested at 4 days post-infection. Protein samples were analyzed by SDS-PAGE (A) and Western blot analysis with E2 monoclonal antibody (B).</p>

Cited by 0Open access

In cellulo structure determination of a novel cypovirus polyhedrin.

Axford, D, Ji, X, Stuart, DI et al. · Oxford University Research Archive (ORA) (University of Oxford) · 2014

This work demonstrates that with the use of a microfocus synchrotron beam the structure of a novel viral polyhedrin could be successfully determined from microcrystals within cells, removing the preparatory step of sample isolation and maintaining a favourable biological environment. The data obtained are of high quality, comparable to that obtained from isolated crystals, and enabled a facile structure determination. A small but significant difference is observed between the unit-cell parameters and the mosaic spread of in cellulo and isolated crystals, suggesting that even these robust crystals are adversely affected by removal from the cell.

Cited by 1Open access

Nucleotide sequence of the Buzura suppressaria single nucleocapsid nuclear polyhedrosis virus polyhedrin gene

Zhìhóng Hú, MengXin Liu, F. Jin et al. · Journal of General Virology · 1993

A portion of the genome of the Buzura suppressaria (Lepidoptera) single nucleocapsid nuclear polyhedrosis virus (BsSNPV) containing the polyhedrin gene was sequenced. An open reading frame of 738 nucleotides encoded a protein of 246 amino acids and represented the polyhedrin gene. A conserved TAAG motif, associated with transcriptional start sites in other polyhedrin genes, was identified 51 nucleotides upstream of the BsSNPV polyhedrin gene. A putative polyadenylation signal, AATAAA, was found immediately downstream of the polypeptide termination codon. Comparison of the amino acid sequence of BsSNPV polyhedrin with other NPV polyhedrins and granulosis virus granulins showed that the BsSNPV polyhedrin was most closely related to the polyhedrin of Orgyia pseudotsugata (Lepidoptera) SNPV and most distantly related to the polyhedrin of Neodiprion sertifer (Hymenoptera) SNPV.

Cited by 30Open access

Effect of mutations on the intracellular localization of Bombyx mori cytoplasmic polyhedrosis virus polyhedrin

Hiroshi Nakazawa, Frédéric Kendirgi, S. Belloncik et al. · Journal of General Virology · 1996

We have already cloned the polyhedrin genes of the wild-type strain H Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) and its mutant, strain A. In this work, polyhedrin genes of mutant BmCPV strains C1 and C2 were cloned and their nucleotide sequences were determined. The polyhedrin amino acid sequences of strains C1 and C2 were compared with that of strain H. Strains C1 and C2 contained two and three sites of mutation in their polyhedrin genes, respectively. Four amino acids (249RLLV) were added at the carboxy terminus of the polyhedrin of strain A, C1 and C2 and the corresponding polyhedrin genes were introduced into a baculovirus expression vector. Intracellular localization of expressed polyhedrin as well as the morphology and localization of polyhedra were investigated by Western blot and microscopy analysis. Recombinant baculovirus containing the polyhedrin gene of strain H produced hexahedral polyhedra in both the cytoplasm and the nucleus. However, the hexahedral polyhedra of strain A were localized only in the nucleus. Normal polyhedra were not observed in cells infected with recombinant baculoviruses expressing strain C1 or C2 polyhedrin genes, but amorphous structures were found in infected cells. Results of expression of a chimaeric luciferase-containing carboxyl-terminal sequence of strain A demonstrated that this sequence was responsible for the nuclear localization. We suggest that a mutation at the carboxy terminus of BmCPV polyhedrin led to nuclear localization of polyhedrin and that several other mutations were responsible for modification of the crystallization pattern of polyhedrin.

Cited by 9

EVALUATING MODIFIED POLYHEDRIN PROMOTERS FOR IMPROVED CO-EXPRESSION OF KRAS4b

Zoe Putman · Maryland Shared Open Access Repository (USMAI Consortium) · 2020

While the baculovirus expression vector system (BEVS) has proved its ability to produce high quality recombinant proteins utilizing a eukaryotic host, limited improvements have been made with regards to expressing multiple proteins. Current co-expression protocols utilize native baculovirus promoters which have limited versatility and varying expression levels. This thesis work aims to address these limitations, through the evaluation of modified AcMNPV polyhedrin promoters with the end goal of identifying novel promoters that display varying levels of expression and provide greater control over the ratio of recombinant proteins produced in the cell. Initial promoter screening measured fluorescence output of an eGFP reporter. Promoters of the most interest were then evaluated for test protein expression to determine their ability to produce more complex proteins. Mutations within the minimal promoter region which disrupt critical promoter elements were found to severely impair promoter activity. On the other hand, those which altered the upstream region beyond the transcription start site had little influence on reporter gene levels. Mutations to the polyhedrin promoter CAGT motif which unexpectedly introduced an alternative translation start site (CAtg), appeared to significantly impact downstream gene expression. When this mutation was in-frame with the reporter gene, eGFP expression levels were found to exceed that of the native promoter. Conversely, minimal eGFP expression was observed when this mutation was not in-frame, suggesting potential use of uORFs to regulate expression. Findings from this work will aid future improvements to the BEVS and will be particularly useful for those seeking to improve co-expression protocols.

Cited by 0Open access

Baculoviral polyhedrin as a novel fusion partner for formation of inclusion body in <i>escherichia coli</i>

Jeong Hyun Seo, Lin Li, Joo Sang Yeo et al. · Biotechnology and Bioengineering · 2003

Baculoviral polyhedrin, which originated from Autographa californica nuclear polyhedrosis virus (AcNPV), was employed for the first time as a novel fusion partner for expression of foreign proteins in an Escherichia coli system. We characterized the expression of recombinant polyhedrin protein fused to green fluorescent protein (GFP). The polyhedrin fusion protein ( approximately 58 kDa) was successfully expressed as an insoluble inclusion body comprising approximately 30% of the total cellular protein. The E. coli expressing polyhedrin-GFP fusion protein showed higher cell growth ( approximately 1.8-fold) and higher GFP yield ( approximately 3.5-fold) than the strain expressing soluble single GFP. Interestingly, the polyhedrin fusion portion showed almost the same characteristics as the native baculoviral polyhedrin; it was rapidly solubilized under alkaline conditions, similar to the conditions found in the insect midgut. In addition, the polyhedrin fusion portion was rapidly digested by alkaline proteases in insect Plutella xylostella midgut as well as by alpha-chymotrypsin, a protease that has similar properties to insect midgut polyhedra-associated alkaline proteases. These unique properties suggest that baculoviral polyhedrin might be an advantageous fusion partner for production of foreign proteins, especially harmful proteins, in E. coli expression systems.

Cited by 16