Riken Corporation

The Institute of Physical and Chemical Research

Aisin Seiki Kabushiki Kaisha

Chiome Bioscience Inc.

Japan Science and Technology Agency

Kazusa Dna Research Institute

Aisin Cosmos R&d Co., Ltd.

National Center or Neurology and Psychiatry

Takehiko Shibata

Kunihiro Ohta

Hidetaka Seo

Nobuhiro Morishima

Yasushi Shigemori

Tsutomu Mikawa

Feng Ling

Keiko Nakanishi

Hikaru Mizumura

Minoru Yoshida

Osamu Ohara

Michio Oishi

Fusao Makishima

Rong Niu

Yu-ichi Goto

Kouji Hirota

The present invention provides a method for obtaining diverse novel genes by inducing somatic cell homologous recombination at genetic loci in somatic cells. By controlling transcription activity of a gene that exists at a genetic locus in a eukaryotic organism cell wherein DNA homologous recombination is occurring at an arbitrary genetic locus, somatic cell homologous recombination is induced between said gene and a gene having a DNA sequence similar to said gene that exists in a region upstream of a transcription promoter, whereby it is possible to obtain diverse novel genes having a plurality of genetic information.

Method of inducing homologous recombination of somatic cell

A method includes providing a eukaryotic cell including mutant mtDNA in which there is at least one mutation in the mtDNA, allowing the cell to come into contact with an active oxygen species or a chemical species that generates such an active oxygen species in the cell (e.g., hydrogen peroxide) and thereby changing the percentage of mutant mtDNA (mitochondrial genomic DNA) in the cell as a result of the contact. Also featured are cells obtained by the above-described method.

Method for generating homoplasmic cells from heteroplasmic cells

The present invention provides a novel method for obtaining diverse antibodies as a result of markedly enhancing the somatic homologous recombination at an antibody locus in immunocytes. By putting immunocytes in which DNA homologous recombination is occurring at an antibody locus (for example, DT40 cells and the like) into contact and the like with histone acetylase inhibitor and the like (for example, trichostatin A and the like), thereby relaxing the chromatin structure at said antibody locus, somatic homologous recombination at an antibody locus is enhanced, and the production of diverse antibody molecules is made possible. The production of antibodies that bind specifically to antigens from cell populations in which the antibody molecules have been diversified by the enhancement of somatic homologous recombination is made possible by using an appropriate selection method (for example, beads coated with antigen and the like).

Method of enhancing homologous recombination of somatic cells and method of constructing specific antibody

The invention establishes a technology that allows non-specific amplification to be inhibited during nucleic acid amplification in an isothermal amplification reaction, such that the amplification efficiency is increased. The invention is a extreme thermophile single-stranded DNA binding mutant protein, having an amino acid sequence that expresses a function that can contribute to increasing an amplification efficiency of a template nucleic acid in an isothermal amplification reaction system that uses a strand displacement polymerase, and having in its amino acid sequence a mutation site where a mutation involving at least one of deletion, substitution, addition, and insertion of one or more amino acids in amino acid sequence of extreme thermophile single-stranded DNA binding protein has occurred, and a method of use thereof.

Extreme thermophile single-stranded DNA binding mutant protein, and nucleic acid isothermal amplification method of use thereof

The present invention relates to a method for increasing genetic recombination frequency in a genomic DNA and a method for inducing genome rearrangement. Specifically, according to the present invention there are provided: the method for increasing genetic recombination frequency in a cell in which genetic recombination takes place at any sites in the genome, comprising causing a restriction enzyme to be expressed in the cell, inducing transient activation of the restriction enzyme, and then introducing 2 or more double strand cleavages into any genomic DNA of the cell, so as to increase the genetic recombination frequency; the method for inducing genome rearrangement through the use of the above method; and cells each prepared through the use of the above 2 methods.

Method of inducing genome reorganization via intracellular activation of thermostable multifrequency DNA-cleaving enzyme

A heat-stable RecA mutant protein is obtained by mutation involving either deletion or substitution of at least one amino acid in an amino acid sequence composing an acid region at C-terminal end of a wild type heat-stable RecA protein, and has an improved ability, compared to the wild type heat-stable RecA protein, for contributing to an increase in an amplification specificity of a template nucleic acid in a nucleic acid amplification reaction.

Heat-stable recA mutant protein and a nucleic acid amplification method using the heat-stable recA mutant protein

An object of the present invention is to provide a nucleic acid amplification method for amplifying a desired nucleic acid while suppressing amplification of byproducts in a PCR reaction, a reagent kit used for nucleic acid amplification, a method of detecting single nucleotide polymorphism to detect single nucleotide polymorphism by utilizing that amplification of byproducts is suppressed in a PCR reaction, and a reagent kit used for detecting single nucleotide polymorphism. The method of amplifying nucleic acids by PCR is characterized by admixing in a reaction solution, a homologous recombinant protein which contains at least one of a RecA protein derived from, and a modified RecA protein obtained by modification of the RecA protein and having a function similar to that of the RecA protein, and carrying out PCR.

Method of amplifying nucleic acids, reagent kit for amplifying nucleic acids, method of detecting single nucleotide polymorphism, and reagent kit for detecting single nucleotide polymorphism

The present invention provides the antibody that react with the cleavage product of vimentin, but not with intact vimentin.

Antibody against cleavage product of vimentin

The present invention relates to a site-specific endonuclease which recognizes a specific nucleotide sequence, to a gene coding for the endonuclease, to a recombinant vector containing the gene, to a transformant containing the vector, and to a process for producing the endonuclease.

Endonuclease

Antibody against cleavage product or vimentin

A multi-step method of detecting a gene in a nuclear chromosome which is involved in mitochondrial recombination is disclosed. The method disclosed includes the steps: a) fusing enucleated .omega..sup.- mitochondrial donor cells expressing a first marker gene with nucleus-containing .omega..sup.+ mitochondrial recipient cells expressing a second marker gene different from the first marker gene to form fused cells wherein the fused cells have one type of mitochondria and b) selecting fused cells that are .omega..sup.+ and express the first and second marker genes to identify those enucleated .omega..sup.- mitochondrial donor cells with a reduced recombination frequency. The method includes the further steps of judging that the gene in a nuclear chromosome of the recipient cells involved in mitochondrial recombination is normal when the mitochondrial recombination frequency is high or that the gene is mutated when the recombination frequency is low. The judging steps permit the detection of a mutant gene in a nuclear chromosome of the recipient cells used for cell fusion. An isolated mhr1 and MHR1 gene coding for a polypeptide is also disclosed.

Growing community of inventors

Saitama, Japan

Takehiko Shibata