173 results about "Essential gene" patented technology

Recombinant poxviruses, such as vaccinia, are provided that comprises a segment comprised of (A) a first DNA sequence encoding a polypeptide that is foreign to poxvirus and (B) a poxvirus transcriptional regulatory sequence, wherein (i) said transcriptional regulatory sequence is adjacent to and exerts transcriptional control over said first DNA sequence and (ii) said segment is positioned within a nonessential genomic region of said recombinant poxvirus. Vaccines, carriers, cells, and media comprising recombinant poxviruses, and methods of immunization with recombinant poxviruses also are provided.

The current invention provides methods to silence insect genes by using unpackaged dsRNA or siRNA, in one embodiment such dsRNA or siRNA is present in plant vascular tissue, preferably phloem, more particularly phloem sap, and the insect is a plant sap-sucking insect. Also provided are DNA sequences which when transcribed yield a double-stranded RNA molecule capable of reducing the expression of an essential gene of a plant sap-sucking insect, methods of using such DNA sequences and plants or plant cells transformed with such DNA sequences. Also provided is the use of cationic oligopeptides that facilitate the entry of dsRNA or siRNA molecules in insect cells, such as plant sap-sucking insect cells.

The invention discloses an insect bioreactor capable of expressing multiple exogenous genes, and a construction method and application thereof. The construction method comprises the following steps: (1) introducing multicopy high-efficiency bacteria DNA (deoxyribonucleic acid) replication initiator into chitinase and cysteine proteinase genes of a baculovirus genome to obtain a baculovirus shuttle plasmid; (2) replacing virus duplicated essential gene downstream the polyhedrosis gene of the baculovirus shuttle plasmid with antibiotic gene to obtain a baculovirus plasmid DNA; and (3) replacingother virus duplicated and infected nonessential genes in the baculovirus shuttle plasmid with reverse selection marker gene to obtain the insect bioreactor. The antibiotic gene or reverse selection marker gene in the insect bioreactor which is constructed by replacing the exogenous target genes can express multiple exogenous genes in a host insect or insect cell. The insect bioreactor disclosed by the invention can efficiently expressing one or more exogenous genes in an insect body at the same time, and can produce massive recombinant proteins at low cost.

A herpes simplex virus (HSV) comprising (i) an HSV LAT sequence inserted into an essential gene of the HSV; and (ii) a deletion in the endogenous LAT region of the HSV strain. The HSV of the invention can be used in the treatment of disorders of, or injuries to, the nervous system of a mammal.

The present invention concerns double stranded RNA compositions and transgenic plants capable of inhibiting expression of essential genes in parasitic nematodes, and methods associated therewith. Specifically, the invention relates to the use of RNA interference to inhibit expression of a target essential parasitic nematode gene, which is a parasitic nematode pas-5 gene, and relates to the generation of plants that have increased resistance to parasitic nematodes.

Disclosed is an Environmentally Limited Viability System (ELVS) for microorganisms based on temperature differences between permissive and non-permissive environments. Viability of the microorganisms are limited to the permissive environment by specifically expressing one or more essential genes only in the permissive environment, or expressing one or more lethal genes only in the non-permissive environment. Environmentally Limited Viability Systems are also disclosed involving coordinate expression of a combination of required genes and lethal genes. Microorganisms containing an Environmentally Limited Viability System are useful for release into a permissive environment. Temperature regulated Environmentally Limited Viability Systems are particularly suited for use with recombinant avirulent Salmonella vaccines by limiting their growth to the warmer environment inside the host. Such vaccines can be administered to protect humans or warm-blooded animals against bacterial, viral, mycotic and parasitic pathogens, especially those that colonize on or invade through mucosal surfaces. This antigen delivery system can also be used for expression of gamete-specific antigens to induce immune responses to block fertilization, or to induce immune responses to tumor antigens. In the event that an individual sheds live vaccine into the environment, the presence of the ELVS prevents survival of the vaccine. When environmentally regulated lethal genes are present on an extrachromosomal element and are regulated by chromosomal genes, transfer of the extrachromosomal element to other microorganisms will be limited by unregulated expression of the lethal genes in the recipient microorganism.

This invention provides a method to silence an endogenous target gene expression in plants by applying a specific dsRNA onto the exterior surface of a plant. Application, such as by spraying or brushing a plant with dsRNA is done without wounding the plant tissue and cells such as by mechanical-type wounding, particle bombardment or mechanical infection with viral vectors. The present invention enables the regulation of gene expression in plants. In some embodiments of the invention, the dsRNA is directed to an essential gene of a plant pathogen or pest, whereby the pathogen and / or pest damage is controlled, resulting in desired agronomic performance.

A mutant herpesvirus that can be used a recombinant virus vector includes (a) a mutation such that the mutant virus has a reduced ability in comparison with a parent type to cause lysis of an infected cell, and (b) an inactivating mutation in a gene essential for the production of infectious virus. An example is a HSV1 mutant lacking the essential glycoprotein gH gene and having a mutation impairing the function of the gene product VP16. A heterologous gene can be carried at the site of the inactivated essential gene, e.g. a gene suitable for administering gene therapy. The vector has an increased margin of safety over known herpesvirus vectors in respect of incidence of cytopathic effects and / or risk of infection.

The present invention provides for improved vectors for use in gene therapy. Utilizing the cancer specific DF3 / MUC1 promoter to drive a replication essential gene, vectors are made conditionally replication-competent, permitting wider infection and expression of tumor cells. In addition, therapeutic genes and adjunct therapies further increase anti-tumor efficacy.

The present invention provides nucleotide sequences, methods and compositions that enable the experimental determination as to whether any gene in the genome of Aspegillus fumigatus is essential, and whether that gene is required for virulence or pathogenicity. The methods involve the construction of genetic mutants in which a target gene is placed under conditional expression. The identification of essential genes and those genes critical to the development of virulent infections, provides a basis for the development of screens for new drugs against Aspergillus fumigatus. The present invention further provides Aspergillum fumigatus genes that are essential and are potential targets for drug screening. The nucleotide sequence of the target genes can be used for various drug discovery purposes, such as expression of the recombinant protein, hybridization assay and construction of nucleic acid arrays. The uses of proteins encoded by the essential genes, and genetically engineered cells comprising modified alleles of essential genes in various screening methods are also encompassed by the invention.

Essential genes coding for the metabolic pathway of solventogenic autotrophic Clostridia were sequenced, and functionality was confirmed. The present invention utilizes a comparative inter-species approach to develop the minimum set of essential genes for metabolic function and estimate productivity in species of suspected solventogenic capability.

Methods are provided for the rapid identification of essential or conditionally essential DNA segments in any species of haploid cell (one copy chromosome per cell) that is capable of being transformed by artificial means and is capable of undergoing DNA recombination. This system offers an enhanced means of identifying essential function genes in diploid pathogens, such as gram-negative and gram-positive bacteria.

The present invention provides C. neoformans genes that are essential and are potential targets for drug screening. The nucleotide sequence of the target genes can be used for various drug discovery purposes, such as expression of the recombinant protein, hybridization assay and construction of nucleic acid arrays. The uses of proteins encoded by the essential genes, and genetically engineered cells comprising modified alleles of essential genes in various screening methods are also encompassed by the invention. The present invention also provides methods and compositions that enable the experimental determination as to whether any gene in the genome of Cryptococcus neoformans is essential, and whether that gene is required for virulence or pathogenicity. The identification of essential genes and those genes critical to the development of virulent infections, provides a basis for the development of screens for new drugs against C. neoformans.

Described herein is a method of treatment of cancer or tumor using a modified bacteria or composition comprising the modified bacteria. In certain embodiments, the method is in combination with other treatment. In certain embodiments, the treatment is chemotherapy, radiation therapy, gene therapy, surgery or a combination thereof. The method makes modified facultative anaerobic bacteria into a conditional obligate anaerobe. The modified bacteria are strictly hypoxia regulated and comprise an essential gene expressing cassette. The vectors of this method comprise the essential gene expressing cassette. Also described herein are therapeutic and prophylactic compositions comprising the modified bacteria. The therapeutic and prophylactic compositions contain a purified form of the modified bacteria, while in certain embodiments, they do not contain other strain of microorganisms. The modified bacteria grow within the solid tumor / cancer, retarding its growth and are rapidly eliminated from normal tissues. The solid tumor / cancer includes breast cancer, liver cancer or neuroblastoma.

The present invention provides methods and compositions that enable the experimental determination as to whether any gene in the genome of a diploid pathogenic organism is essential, and whether it is required for virulence or pathogenicity. The methods involve the construction of genetic mutants in which one allele of a specific gene is inactivated while the other allele of the gene is placed under conditional expression. The identification of essential genes and those genes critical to the development of virulent infections, provides a basis for the development of screens for new drugs against such pathogenic organisms. The present invention further provides Candida albicans genes that are demonstrated to be essential and are potential targets for drug screening. The nucleotide sequence of the target genes can be used for various drug discovery purposes, such as expression of the recombinant protein, hybridization assay and construction of nucleic acid arrays. The uses of proteins encoded by the essential genes, and genetically engineered cells comprising modified alleles of essential genes in various screening methods are also encompassed by the invention.

The present invention provides methods and compositions that enable the experimental determination as to whether any gene in the genome of a diploid pathogenic organism is essential, and whether it is required for virulence or pathogenicity. The methods involve the construction of genetic mutants in which one allele of a specific gene is inactivated while the other allele of the gene is placed under conditional expression. The identification of essential genes and those genes critical to the development of virulent infections, provides a basis for the development of screens for new drugs against such pathogenic organisms. The present invention further provides Candida albicans genes that are demonstrated to be essential and are potential targets for drug screening. The nucleotide sequence of the target genes can be used for various drug discovery purposes, such as expression of the recombinant protein, hybridization assay and construction of nucleic acid arrays. The uses of proteins encoded by the essential genes, and genetically engineered cells comprising modified alleles of essential genes in various screening methods are also encompassed by the invention.

A mutant herpesvirus that can be used as a recombinant virus vector comprises (a) a mutation such that the mutant virus has a reduced ability in comparison with a parent type to cause lysis of an infected cell, and (b) an inactivating mutation in a gene essential for the production of infectious virus. An example is a HSV1 mutant lacking the essential glycoprotein gH gene and having a mutation impairing the function of gene product VP16. A heterologous gene can be carried at the site of the inactivated essential gene, e.g. a gene suitable for administering gene therapy. The vector has an increased margin of safety over known herpesvirus vectors in respect of incidence of cytopathic effects and / or risk of reversion.

The invention relates to a new usage of a neural stem cell differentiating related gene DCF1. The invention sieves protein ATP1B1 interacted with DCF1 through utilizing a yeast-two hybrid technology and is positioned altogether by using cell fluorescence, and the interaction is confirmed through immunity and precipitation. According to a literature report, the interaction between ATP1B1 and BACE1 exists, but BACE1 is an essential gene of the development of AD (Alzheimer disease). After DCF1 is muted through a RNAi method, the expression of ATP1B1 and BACE1 also changes remarkably the results prove that the expression of BACE1 can be adjusted and controlled through certain signal passages of DCF1, certain relation exists in the occurrence and the development of DCF1 and AD, which is possible to be a new drug effect target spot of AD treatment, the interaction of DCF1 and ATP1B1 is found, and the invention has a vital significance to a signal conducting mechanism during the understanding process of the development and the progression of AD.

The present invention provides a herpes virus in which a non-essential gene for replication is inactivated More particularly, the present invention provides a herpes virus in which a non-essential gene for replication present in a UL or US region is inactivated. More preferably, the non-essential gene for replication contains US3 or UL56. The herpes virus may be preferably a herpes simplex virus, and more preferably herpes simplex virus 1 or herpes simplex virus 2. The present invention provides a method, composition and use for treating various diseases or disorders including tumor and infectious diseases. The present invention also provides a method, composition and use for activating a prodrug.

The present invention concerns double stranded RNA compositions and transgenic plants capable of inhibiting expression of essential genes in parasitic nematodes, and methods associated therewith. Specifically, the invention relates to the use of RNA interference to inhibit expression of a target essential parasitic nematode gene, which is a parasitic nematode pas-5 gene, and relates to the generation of plants that have increased resistance to parasitic nematodes.

The invention belongs to the field of gene therapy, and particularly relates to a preparation method and system of recombinant adeno-associated virus and recombinant bacmids. Firstly, constructing recombinant bacmids of a recombinant baculovirus genome containing necessary functional elements for producing the recombinant adeno-associated virus; wherein at least one necessary functional element isinserted into the N terminal or the C terminal of the necessary locus of the recombinant baculovirus genome; and then transfecting the obtained recombinant bacmids containing the recombinant baculovirus genome for producing the recombinant adeno-associated virus into a host cell line for culturing to prepare the recombinant adeno-associated virus. Compared with a recombinant baculovirus obtainedby preparing recombinant bacmids through traditional Tn7 recombination, the recombinant baculovirus obtained by inserting core elements containing Cap, Rep and ITR into the two sides of an essential gene of the baculovirus has the advantages that the production level of continuous passage rAAV in cells is more stable, and the rAAV yield is higher.

The present invention relates to main structure gene VP2 of artificial constructed pseudorabies virus, PrV and porcine parvovirus, PPV. In the pseudorabies virus genome in which the main toxicity gene (TK) and virus generation nonessential gene (gG) are deleted the VP2 gene of porcine parvovirus can be site-specifically inserted to make it be positioned in strong late promoter downstream of pseudorabies virus, and the inserted exogenous gene coded protein has good immunogenicity, and can stimulate swine to produce protective immune reaction for resisting two virulent challenges of porcine parvovirus and pseudorabies virus. Said invention also includes recombinant pseudorabies virus, Hzau AVL-PRppvV-VP2, vaccine prepared by using it and its preparation method.

A bacterial host cell comprising at least two copies of an amplification unit in its genome, said amplification unit comprising: i) at least one copy of a gene of interest, and ii) an expressible conditionally essential gene, wherein the conditionally essential gene is either promoterless or transcribed from a heterologous promoter having an activity substantially lower than the endogenous promoter of said conditionally essential gene, and wherein the conditionally essential gene if not functional would render the cell auxotrophic for at least one specific substance or unable to utilize one or more specific sole carbon source; methods for producing a protein using the cell of the invention, and methods for constructing the cell of the invention.

The present invention provides viral vectors that have been engineered to contain a synthetic promoter that controls at least one essential gene. The synthetic promoter is induced by a specific gene product not normally produced in the cells in which the viral vector is to be transferred. The vectors are propagated in producer or helper cells that express the inducing factor, thereby permitting the virus to replicate to high titer. The lack of the inducing factor in the target cells precludes viral replication, however, meaning that no vector toxicity or immunogenicity arises. Where the virus carries a gene of interest, this should provide for higher level expression for longer periods of time than with current vectors. Methods for making the vectors, helper cells, and their use in protein production, vaccines and gene therapy are disclosed.

The invention provides a method for generating a database of candidate essential genes in Staphylococcus aureus, as well as otherwise important genes that, when mutated, lead to a growth attenuated phenotype. Such genes and mutants of such genes are important for identifying antibacterial agents suitable for treating and preventing S. aureus infections. The invention includes methods for confirming the essentiality or importance of candidate genes, as well as methods for utilizing those genes to screen for new antibacterial drugs. The invention also includes the antibacterial agents identified using the disclosed methods, as well as methods of using the same for treating and preventing Staphylococcus infection.

The invention discloses a bombyx mori nuclear polyhydrosis virus (BmNPV) 39k inducible promoter and application thereof. A nucleotide sequence of the promoter is shown as SEQ ID No.1; the promoter has obvious BmNPV inducible promotion activity and can make cells start foreign gene expression when the cells are subjected to the BmNPV infection; an RNAi vector using a BmNPV multiplication essential gene as a target can be built by utilizing the promoter; the abundant expression of shRNA can be performed when the bombyx mori is subjected to the BmNPV infection; the shRNA is cut into siRNA in a cell by an enzyme; specific degradation is performed on the BmNPV multiplication essential gene mRNA to initiate the BmNPV multiplication essential gene to be transcribed and then silenced, so the aim of inhibiting the virus multiplication is fulfilled, and the promoter can be used for preventing and controlling the BmNPV infection of the bombyx mori, performing genetic engineering breeding of bombyx mori anti-BmNPV strains and providing a good reference mode for transgenic therapy of other biologic virus diseases.

One embodiment of the invention provides a genetically enhanced cyanobacterium producing a first chemical compound comprising:a genetically enhanced genome with a first gene inactivation in a first essential or conditionally essential gene of the cyanobacterium, anda first extrachromosomal plasmid harboring the first essential or conditionally essential gene and at least one first production gene for production of the first chemical compound,wherein the cyanobacterium lacks a functional gene conferring biocide resistance.These cyanobacteria can produce a first valuable chemical compound in long-term cultures without the need to employ genes conferring biocide resistance.

The invention provides a microbicidal composition comprising at least one siRNA. The siRNA is an RNA duplex made of one or two molecules. A portion of the siRNA is identical to a target sequence in an essential gene of a virus. The virus may be a herpesvirus, for example, HSV-1 or HSV-2. Preferably, the herpesvirus is HSV-2. The microbicidal composition further comprises a pharmaceutically acceptable carrier. Also included in the invention are methods to prevent and treat viral infections by administration of the microbicidal composition. Preferably, the microbicidal composition is administered transmucosally.

The invention provides cells and methods of using the cells for the propagation of replication-deficient adenoviral vectors. The cells comprise at least one heterologous nucleic acid sequence which upon expression produces at least one non-adenoviral gene product that complements in trans for a deficiency in at least one essential gene function of one or more regions of an adenoviral genome so as to propagate a replication-deficient adenoviral vector comprising an adenoviral genome deficient in the at least one essential gene function of the one or more regions when present in the cell.