The present invention relates to the field of bacterial vectors and methods for genetic manipulation of bacteria. In particular, the present invention relates to a vector for genetic manipulation of a bacterium, wherein said vector comprises (a) a non-antibiotic selection marker gene cassette, (b) an origin of replication, wherein said origin of replication is not capable of inducing replication of said vector in said bacterium, and (c) a restriction endonuclease gene, a recognition site of a restriction endonuclease encoded by said restriction endonuclease gene, and a second regulatory sequence. Further, the invention relates to a bacterial host cell comprising said vector, a method for genetic manipulation of bacteria using the vector of the invention, and methods for selecting bacterial host cells.

Methods, reagents and compositions for providing more accurate and reliable genetic modification are provided. In particular a nucleic acid encoding a fusion protein comprising an endonuclease domain and a binding domain for an origin of replication is described. Also provided are methods, reagents and compositions for in vivo genetic modification of the genome of a non-animal cell or organism. Furthermore, the present application relates to uses of the said methods, reagents and compositions for introducing desirable traits to non-animal organisms or ameliorating or removing non-desirable traits in these organisms including in the treatment of disease.

The present invention discloses a SmartBac baculovirus expression system and application thereof. The system can comprise a acceptor plasmid (containing fragment A or fragments B and C) and a donor plasmid (containing fragment D); the fragment A contains a promoter, a sequence encoding a protease, a protease cleavage site, an insertion region of a gene encoding a target object to be expressed and a termination sequence; the fragment B contains a promoter, a sequence encoding a protease and a termination sequence; the fragment C contains a promoter, an insertion region of a gene encoding a target object to be expressed and a termination sequence; the fragment D contains a promoter, an insertion region of a gene encoding a target object to be expressed and a termination sequence. The present invention also provides three cloning strategies to achieve the expression of protein complexes with molecular weights of less than 600 kDa and the expression of protein complexes with molecular weights of no less than 600 kDa and efficient screening of a subunit most suitable for adding a purification tag. The present invention is of great significance for recombinantly expressing protein complexes with complex components and large molecular weights in insect cells.

Provided herein, in certain embodiments, are plasmid expression vectors and methods of use of such vectors for either transient or stable integrated expression of transgenes in eukaryotic cells. The plasmid expression vectors provided herein are less than 3.6 kb in size and can accommodate large (>5 kb) polynucleotide insertions of transgenes and homology arms for stable integration.

Nucleic acids encoding Parvoviral Rep proteins with a mutated nuclear localization signal (NLS) are provided. Also provided is a nucleic acid comprising a nucleotide sequence encoding a Parvoviral Rep protein with a mutated zinc finger domain and a nucleic acid comprising a nucleotide sequence encoding a Parvoviral Rep protein comprising an amino acid mutation at position 43, 57, 79, 97, 120, 179, 305, 484, 493 or 571 with reference to SEQ ID NO: 2. Nucleic acid constructs and cells, such as insect cells, comprising the nucleic acids are provided as well as a method for producing a recombinant Parvoviral virion using the nucleic acids.

The invention relates to a method for initiating the replication of a deoxyribonucleic acid molecule, said method comprising a step of inserting, into said deoxyribonucleic acid molecule, at least one nucleic acid molecule representing a multicellular DNA replication origin, the replication origin comprising at least nine nucleotides, the at least nine nucleotides consisting of at least three uninterrupted origin repeating elements (OGRE).

Provided is a gene expression cassette for stably and highly producing a protein of interest. The gene expression cassette has a structure in which a DNA construct (X) containing a gene of interest and a poly A addition sequence is sandwiched between a promoter (P) and an enhancer (P), the gene expression cassette further including transposon sequences (T) upstream of the promoter (P) and downstream of the enhancer (P). Further, in the gene expression cassette, when a nuclear matrix binding sequence (M) is appropriately arranged upstream of a replication initiation sequence (S) in combination with the transposon sequence (T), the protein of interest can be more effectively produced stably and in a large amount. For example, HRG, PD-1, EMMPRIN, NPTN, EMB, RAGE, MCAM, ALCAM, ErbB2, and an antibody can each be produced stably and in a large amount.

Nucleic acids encoding Parvoviral Rep proteins with a mutated nuclear localization signal (NLS) are provided. Also provided is a nucleic acid comprising a nucleotide sequence encoding a Parvoviral Rep protein with a mutated zinc finger domain and a nucleic acid comprising a nucleotide sequence encoding a Parvoviral Rep protein comprising an amino acid mutation at position 43, 57, 79, 97, 120, 179, 305, 484, 493 or 571 with reference to SEQ ID NO: 2. Nucleic acid constructs and cells, such as insect cells, comprising the nucleic acids are provided as well as a method for producing a recombinant Parvoviral virion using the nucleic acids.

Nucleic acids encoding Parvoviral Rep proteins with a mutated nuclear localization signal (NLS) are provided. Also provided is a nucleic acid comprising a nucleotide sequence encoding a Parvoviral Rep protein with a mutated zinc finger domain and a nucleic acid comprising a nucleotide sequence encoding a Parvoviral Rep protein comprising an amino acid mutation at position 43, 57, 79, 97, 120, 179, 305, 484, 493 or 571 with reference to SEQ ID NO: 2. Nucleic acid constructs and cells, such as insect cells, comprising the nucleic acids are provided as well as a method for producing a recombinant Parvoviral virion using the nucleic acids.

Methods, reagents and compositions for providing more accurate and reliable genetic modification are provided. In particular a nucleic acid encoding a fusion protein comprising an endonuclease domain and a binding domain for an origin of replication is described. Also provided are methods, reagents and compositions for in vivo genetic modification of the genome of a non-animal cell or organism. Furthermore, the present application relates to uses of the said methods, reagents and compositions for introducing desirable traits to non-animal organisms or ameliorating or removing non-desirable traits in these organisms including in the treatment of disease.