Abstract: The present invention intends to provide an assay system using split luciferase that has a remarkably high detection sensitivity. In an embodiment, binding of mutually binding first and second proteins is detected by preparing a first fusion protein comprising the first protein fused with a peptide having the amino acid sequence of amino acid SEQ ID NO: 1 and a second fusion protein comprising the second protein fused with a peptide having an amino acid sequence selected from the group consisting of amino acid SEQ ID NOS: 2 to 6, and allowing the first fusion protein to bind with the second fusion protein to form a complex, and detecting luminescence emitted from the complex.

Abstract: The present invention intends to provide an assay system using split luciferase that has a remarkably high detection sensitivity. In an embodiment, binding of mutually binding first and second proteins is detected by preparing a first fusion protein comprising the first protein fused with a peptide having the amino acid sequence of amino acid SEQ ID NO: 1 and a second fusion protein comprising the second protein fused with a peptide having an amino acid sequence selected from the group consisting of amino acid SEQ ID NOS: 2 to 6, and allowing the first fusion protein to bind with the second fusion protein to form a complex, and detecting luminescence emitted from the complex.

Abstract: The present invention provides an expression vector which is effective in an efficient establishment of transformed cells which express the aimed protein gene in a high level. An expression vector which has a cassette for expressing the drug selective marker gene containing mRNA destabilizing sequence, at least one element for stabilizing the gene expression and a cassette for expressing the gene of the aimed protein. Preferably, the mRNA destabilizing sequence is derived from AT-rich sequence existing in the 3?-untranslated region of cytokine, interleukin or proto-oncogene, and the element for stabilizing the gene expression is derived from Chinese hamster genome.

Abstract: The present invention intends to provide an assay system using split luciferase that has a remarkably high detection sensitivity. In an embodiment, binding of mutually binding first and second proteins is detected by preparing a first fusion protein comprising the first protein fused with a peptide having the amino acid sequence of amino acid SEQ ID NO: 1 and a second fusion protein comprising the second protein fused with a peptide having an amino acid sequence selected from the group consisting of amino acid SEQ ID NOS: 2 to 6, and allowing the first fusion protein to bind with the second fusion protein to form a complex, and detecting luminescence emitted from the complex.

Abstract: The present invention provides a gene construct encoding pH insensitive luciferase for visualizing intracellular information, wherein an intracellular expression activity is higher compared with a gene construct of luciferase derived from a firefly.

Abstract: The present invention intends to provide an assay system using split luciferase that has a remarkably high detection sensitivity. In an embodiment, binding of mutually binding first and second proteins is detected by preparing a first fusion protein comprising the first protein fused with a peptide having the amino acid sequence of amino acid SEQ ID NO: 1 and a second fusion protein comprising the second protein fused with a peptide having an amino acid sequence selected from the group consisting of amino acid SEQ ID NOS: 2 to 6, and allowing the first fusion protein to bind with the second fusion protein to form a complex, and detecting luminescence emitted from the complex.

Abstract: The present invention provides an expression vector which is effective in an efficient establishment of transformed cells which express the aimed protein gene in a high level. An expression vector which has a cassette for expressing the drug selective marker gene containing mRNA destabilizing sequence, at least one element for stabilizing the gene expression and a cassette for expressing the gene of the aimed protein. Preferably, the mRNA destabilizing sequence is derived from AT-rich sequence existing in the 3?-untranslated region of cytokine, interleukin or proto-oncogene, and the element for stabilizing the gene expression is derived from Chinese hamster genome.

Abstract: The present invention provides a gene construct encoding pH insensitive luciferase for visualizing intracellular information, wherein an intracellular expression activity is higher compared with a gene construct of luciferase derived from a firefly.

Abstract: The present invention provides a gene construct encoding pH insensitive luciferase for visualizing intracellular information, wherein an intracellular expression activity is higher compared with a gene construct of luciferase derived from a firefly.

Abstract: A compound of formula (1) and an immunoassay method for quantitative determination of dioxins in a sample using as a standard the compound of the following formula (1): wherein R1, R2, R3 and R4 may be the same or different and represent chlorine or hydrogen, n is an integer from 1 to 10, and Z represents an amino acid residue or peptide.

Abstract: A compound of formula (1) and an immunoassay method for quantitative determination of dioxins in a sample using as a standard the compound of the following formula (1): wherein R1, R2, R3 and R4 may be the same or different and represent chlorine or hydrogen, n is an integer from 1 to 10, and Z represents an amino acid residue or peptide.

Abstract: The present invention provides a method capable of simultaneous processing of plural test samples for the receptor binding property of a chemical substance, which does not require imobilization of the receptor or a special device, and a reagent to be used for this method. That is a method for assaying the receptor binding property of an assay target substance is provided, the method comprising the steps of (a) competitively reacting a known concentration of a ligand and the assay target substance with a known concentration of the receptor in a solution, (b) measuring, without physically removing the ligand bound with the receptor prior to the assay, the amount of a free ligand in the solution using one or more antibodies against the ligand, and (c) determining the receptor binding property of the assay target substance using the amount of the free ligand as an index.

Abstract: The present invention provides a method capable of simultaneous processing of plural test samples for the receptor binding property of a chemical substance, which does not require immobilization of the receptor or a special device, and a reagent to be used for this method. That is a method for assaying the receptor binding property of an assay target substance is provided, the method comprising the steps of (a) competitively reacting a known concentration of a ligand and the assay target substance with a known concentration of the receptor in a solution, (b) measuring, without physically removing the ligand bound with the receptor prior to the assay, the amount of a free ligand in the solution using one or more antibodies against the ligand, and (c) determining the receptor binding property of the assay target substance using the amount of the free ligand as an index.

Abstract: The present invention provides a method capable of simultaneous processing of plural test samples for the receptor binding property of a chemical substance, which does not require immobilization of the receptor or a special device, and a reagent to be used for this method. That is a method for assaying the receptor binding property of an assay target substance is provided, the method comprising the steps of (a) competitively reacting a known concentration of a ligand and the assay target substance with a known concentration of the receptor in a solution, (b) measuring, without physically removing the ligand bound with the receptor prior to the assay, the amount of a free ligand in the solution using one or more antibodies against the ligand, and (c) determining the receptor binding property of the assay target substance using the amount of the free ligand as an index.