Gene expressing analysis tool

The present invention relates to a novel research tool for analyzing the expression of Macaca fascicularis genes and use thereof. More particularly, the present invention relates to a Macaca fascicularis gene expression analysis tool comprising a subset of gene transcription products of Macaca fascicularis , and a method of analyzing the expression of Macaca fascicularis genes using the tool and the like.

Macaca fascicularis is mostly used in preclinical tests for drug development, and the data of toxicity tests, biochemical and pathological tests and the like have been accumulated. Particularly in toxicity tests, monkey, a primate, is expected to provide more useful data than do rodents such as rat, mouse and the like for extrapolation to human. However, the influence of side effects on various aspects cannot be observed easily from the changes of existent toxicity markers. Particularly, in the initial stages of drug development, therefore, a method of analyzing toxic reactions at a gene expression level attracts attention.

Among others, the microarray technique that simultaneously monitors expression of several to tens of thousand of mRNAs (see patent references 1-4, non-patent references 1 and 2 and the like for DNA microarray) is increasingly utilized for elucidation of mechanism of toxicity and study of toxicity prediction, and expected as a new research field called toxicogenomics. Toxicity phenomena are considered to accompany not only independent changes of one to several genes but also integrated changes wherein many genes are interrelated, such as interaction between genes and cascade and the like. Therefore, use of microarray, a technique permitting analysis at a transcriptome level, is expected to enable comprehensive understanding of the behavior of molecules involved in toxicity expression.

As a DNA microarray for the analysis of the gene expression of non-human primates, GeneChip (registered trade mark) manufactured by Affymetrix containing Macaca mulatta ESTs is known. However, Macaca fascicularis is mainly used as an experimental animal in Japan. Nevertheless, the current available public database scarcely contains the annotation information of Macaca fascicularis.

For example, when searching a gene that can be used as a marker of drug toxicity and the like, reference (internal standard) genes are necessary for detecting changes in gene expression caused by drug administration. As such genes, genes expressed non-specifically to tissue and time and at a relatively high level, i.e., housekeeping genes, are generally used (e.g., see patent reference 5 and the like for human housekeeping gene). As mentioned above, however, the information of Macaca fascicularis gene is considerably limited, and many aspects of housekeeping gene are unknown.

patent reference 1: U.S. Pat. No. 5,474,796 patent reference 2: WO95/251116 patent reference 3: WO95/35505 patent reference 4: U.S. Pat. No. 5,605,662 patent reference 5: JP-A-2004-135552 non-patent reference 1: Schena M. et al., Proc. Natl. Acad. Sci. USA, Vol. 93, pp. 10614-10619 (1996) non-patent reference 2: Heller R. A. et al., Proc. Natl. Acad. Sci. USA, Vol. 94, pp. 2150-2155 (1997)

Problems to be Solved by the Invention

Accordingly, it is an object of the present invention to identify housekeeping genes of Macaca fascicularis , and to provide a gene expression analysis tool, for example, DNA microarray, for Macaca fascicularis , which contains the genes. A further object of the present invention is to provide a method of analyzing the expression of Macaca fascicularis gene(s) using the gene expression analysis tool.

Means of Solving the Problems

In an attempt to achieve the above-mentioned objects, the present inventors have analyzed EST from 6 major organs (liver, kidney, heart, lung, spleen, testis), identified about 16,000 unique sequences, designed 60 mer oligonucleotide probes based on the information and prepared a DNA microarray. As a result of expression analyses using mRNAs derived from various organs, the inventors have identified 14 kinds of genes expressed in all of the above organs at a relatively high level as housekeeping genes of Macaca fascicularis.

The present inventors have further studied based on such findings, and completed the present invention.

Accordingly, the present invention provides:

[1] a Macaca fascicularis gene expression analysis tool comprising a set of nucleic acids each comprising base sequences the same or substantially the same as each of the base sequences of two or more kinds of nucleic acids selected from the group consisting of 14 kinds of Macaca fascicularis gene transcription products comprising the base sequences shown by SEQ ID NOs: 1-14, respectively, or partial sequences thereof;

[2] the tool of the above-mentioned [1], comprising one or more kinds of nucleic acids comprising base sequences the same or substantially the same as base sequences of Macaca fascicularis gene transcription products other than the aforementioned 14 kinds of Macaca fascicularis gene transcription products, or partial sequences thereof;

[3] the tool of the above-mentioned [1], comprising one or more kinds of nucleic acids comprising base sequences the same or substantially the same as base sequences of a Macaca fascicularis gene transcription product specifically expressed in an organ selected from the group consisting of liver, kidney, heart, lung, spleen and testis, and/or corresponding to a drug efficacy target in human, or partial sequences thereof;

[4] the tool of any of the above-mentioned [1] to [3], wherein the set of the nucleic acids is immobilized on a solid phase carrier;

[5] a method of analyzing the expression of Macaca fascicularis gene(s), comprising measuring gene transcription product(s) in Macaca fascicularis sample(s) using one or more kinds of the tools of the above-mentioned [1] to [4]; and [6] the method of the above-mentioned [5], wherein the Macaca fascicularis sample(s) is(are) taken from a Macaca fascicularis disease model or Macaca fascicularis administered with pharmaceutical agent(s), or isolated Macaca fascicularis cell(s) or tissue(s) exposed to pharmaceutical agent(s); and the like.

Effect of the Invention

Since the gene analysis tool of the present invention contains at least two kinds of housekeeping genes of Macaca fascicularis , it affords a superior effect in that expressions of Macaca fascicularis gene can be quantitatively compared with each other with high accuracy.

The gene expression analysis tool of the present invention characteristically contains at least a set of nucleic acids capable of detecting two or more kinds of housekeeping gene transcription products of Macaca fascicularis (hereinafter sometimes to be referred to as “the nucleic acid set of the present invention”), namely, a set of nucleic acids comprising base sequences the same or substantially the same as base sequences of two or more kinds of housekeeping gene transcription products of Macaca fascicularis , or partial sequences thereof. The form of the “gene expression analysis tool” is not particularly limited as long as it contains the above-mentioned set of nucleic acids and includes, but is not limited to, a kit containing, as a component, a reagent comprising each nucleic acid, and a device, apparatus and the like wherein each nucleic acid is immobilized on a solid phase carrier such as array, microplate and the like. The “housekeeping gene” here means a gene commonly expressed in at least liver, kidney, heart, lung, spleen and testis of Macaca fascicularis at a high level above a certain level.

Specifically, as a housekeeping gene transcription product of Macaca fascicularis, 14 kinds of nucleic acids containing base sequences shown by SEQ ID NOs: 1-14, respectively [in the case of RNA, “t” is read as “u”. While Sequence Listing shows sense strand sequences alone, the “base sequence shown by SEQ ID NO: n” in the present specification includes antisense strand and double strand, unless otherwise specified] can be mentioned. Here, the “gene transcription product” is used as a concept encompassing mRNA, as well as double stranded nucleic acid such as cDNA, cRNA and the like. The Macaca fascicularis genes containing the base sequences shown by SEQ ID NOs: 1-14 have been named as follows by the Gene Nomenclature Committee (HUGO Nomenclature Committee, HGNC).

The “base sequence substantially the same” is a base sequence capable of hybridizing to any of the 14 kinds of nucleic acids under highly stringent conditions, which is different from the base sequence of the corresponding region of a nucleic acid ortholog of other mammal. Here, the “highly stringent conditions” mean a hybridization reaction in 6×SSC (sodium chloride/sodium citrate) at 45° C. and subsequent washing once or more with 0.2×SSC/0.1% SDS at 65° C. Examples of the each base sequence substantially the same as the base sequence of each of the 14 kinds of nucleic acids include a base sequence having a homology of 95% or more, preferably 96% or more, more preferably 97% or more, particularly preferably 98% or more, to the base sequence of each of the 14 kinds of nucleic acids. The homology of the base sequence in the present specification can be calculated using a homology calculation algorithm NCBI BLAST (National Center for Biotechnology Information Basic Local Alignment Search Tool) and under the following conditions (expectancy=10; gap allowed; filtering=ON; match score=1; mismatch score=−3).

Examples of each nucleic acid constituting the nucleic acid set of the present invention include a nucleic acid (probe) capable of specifically hybridizing to a housekeeping gene transcription product derived from Macaca fascicularis , which is a detection target, a pair of oligonucleotides (primers) capable of acting as a primer for amplifying a part or the whole of the transcription product, and the like. The nucleic acid may be a DNA or an RNA, or a DNA/RNA chimera, with preference given to a DNA.

The nucleic acid to be used as a probe may be double stranded or single stranded. When double stranded, it may be a double stranded DNA, a double stranded RNA or a DNA:RNA hybrid. When single stranded, a sense strand (e.g., for cDNA, cRNA) or an antisense strand (e.g., for mRNA, cDNA) is selected according to the sample to be tested and used. The length of the nucleic acid is not particularly limited as long as it can specifically hybridize to a target nucleic acid and is, for example, about 15 bases or longer, preferably about 30 bases or longer. The nucleic acid is preferably labeled with label reagent(s) to enable detection and quantification of the target nucleic acid. As the label reagent, for example, radioisotope, enzyme, fluorescent substance, luminescent substance and the like can be used. As the radioisotope, for example, [ 32 P], [ 3 H], [ 14 C] and the like can be used. As the enzyme, a stable enzyme having high specific activity is preferable and, for example, β-galactosidase, β-glucosidase, alkaline phosphatase, peroxidase, malate dehydrogenase and the like can be used. As the fluorescent substance, for example, fluorescamine, fluorescein isothiocyanate and the like can be used. As the luminescent substance, for example, luminol, luminol derivative, luciferin, lucigenin and the like can be used. Moreover, biotin-(strept)avidin can also be used for binding of a probe and label reagent(s). To immobilize a nucleic acid to be a probe on a solid phase, a nucleic acid in a sample can be labeled with label reagent(s) such as those mentioned above.

The set of oligonucleotides to be used as primers is not particularly limited as long as the oligonucleotides can specifically hybridize to the sense strand and antisense strand of Macaca fascicularis -derived housekeeping gene transcription products containing the base sequences shown by respective SEQ ID NOs, and can amplify DNA fragments between them. An example thereof is a set of oligo DNAs each having a length of about 15—about 100 bases, preferably about 15—about 50 bases, and designed to amplify a DNA fragment of about 100 bp-several kbps.

The nucleic acid that acts as a probe capable of detecting a Macaca fascicularis -derived housekeeping gene transcription product can be acquired by amplifying a desired length of a nucleic acid by PCR using the above-mentioned primer set capable of amplifying a part or whole of a transcription product of the gene, and cDNA or genomic DNA derived from any cell of Macaca fascicularis [e.g., hepatocyte, splenocyte, nerve cell, glial cell, pancreatic β cell, bone marrow cell, mesangial cell, Langerhans cell, epidermal cell, epithelial cell, goblet cell, endothelial cell, smooth muscle cell, fibroblast, fibrocyte, muscle cell, adipocyte, immune cell (e.g., macrophage, T cell, B cell, natural killer cell, mast cell, neutrophil, basophil, eosinophil, monocyte), megakaryocyte, synovial cell, chondrocyte, osteocyte, osteoblast, osteoclast, mammary cell, hepatocyte or interstitial cell, or precursor cell, stem cells or cancer cell of these cells and the like] or any tissue in which such cell is present [for example, brain, a part of brain (e.g., olfactory bulb, amygdaloid nucleus, basal ganglia, hippocampus, thalamus, hypothalamus, cerebral cortex, medulla oblongata, cerebellum), spinal cord, pituitary gland, stomach, pancreas, kidney, liver, gonad, thyroid gland, gall bladder, bone marrow, adrenal gland, skin, lung, gastrointestinal tract (e.g., large intestine, small intestine), blood vessel, heart, thymus, spleen, submandibular gland, peripheral blood, prostate, orchis, ovary, placenta, uterus, bone, articular, adipose tissue, skeletal muscle and the like] as a template, or cloning the above-mentioned housekeeping gene(s) or cDNA(s) from a CDNA or genomic DNA library from the aforementioned cell or tissue by colony or plaque hybridization and the like and preparing a fragment having a suitable length using, where necessary, a restriction enzyme and the like. The hybridization can be performed, for example, according to the method described in Molecular Cloning, 2 nd edition, and the like. When using a commercially available library, hybridization can be performed according to the method described in the instruction manual attached to the library. Alternatively, the nucleic acid can also be obtained based on the information of each base sequence (e.g., base sequences shown by SEQ ID NOs: 1-14) of Macaca fascicularis -derived housekeeping gene product, by chemically synthesizing a part or whole of the base sequence and/or its complementary sequence, using a commercially available DNA/RNA automatic synthesizer and the like. In addition, a chip (array) with a solid phased nucleic acid can also be prepared by directly synthesizing the nucleic acid in situ (on chip) on a solid phase such as silicon, glass and the like.

The gene expression analysis tool of the present invention may contain, in addition to a set of nucleic acids capable of detecting two or more kinds of housekeeping gene transcription products of Macaca fascicularis , one or more kinds of nucleic acids comprising base sequences the same or substantially the same as base sequences of Macaca fascicularis gene transcription products other than the aforementioned 14 kinds of Macaca fascicularis gene transcription products, or partial sequences thereof. Any kind and any number of such nucleic acids can be appropriately selected according to the purpose of use of the gene expression analysis tool of the present invention. For comprehensive analysis of the expression of Macaca fascicularis gene, for example, the tool can contain all gene products that are expressed in any organ, tissue and the like, and further, a nucleic acid for detecting the products of all genes on the genome. For detection of the expression of a particular toxicity marker or disease marker gene, for example, the tool can contain only a nucleic acid for detecting the objective gene product, besides the above-mentioned nucleic acid for the detection of a housekeeping gene.

In a preferable embodiment, such nucleic acid contains a base sequence the same or substantially the same as the base sequence of a Macaca fascicularis gene transcription product specifically expressed in organs such as liver, kidney, heart, lung, spleen, testis and the like, or corresponding to a drug efficacy target in human, or a partial sequence thereof. A gene expressed in an organ specific manner can be acquired by comparing the expressions of respective genes in various organs shown in the Examples below, and selecting a gene whose expression is detected in a particular organ.

Such nucleic acids can be provided as a solid in a dry state or in the form of an alcohol precipitate, or also in a dissolved state in water or suitable buffer (e.g., TE buffer etc.). When used as a labeled probe, the nucleic acid may be previously labeled with any of the above-mentioned labeling substances, or may be provided separately from labeling substances and labeled when in use.

Alternatively, the nucleic acid can also be provided as immobilized on a suitable solid phase. Examples of the solid phase include, but are not limited to, glass, silicon, plastic, nitrocellulose, nylon, polyvinylidene difluoride and the like. Examples of the immobilizing means include, but are not limited to a method by introducing in advance, a functional group such as amino group, aldehyde group, SH group, biotin and the like into a nucleic acid, introducing a functional group (e.g., aldehyde group, amino group, SH group, streptavidin and the like) capable of reacting with the nucleic acid onto a solid phase, and crosslinking the solid phase and the nucleic acid by a covalent bond between the both functional groups, or a method by coating a solid phase with polycation and immobilizing the polyanionic nucleic acid by electrostatic binding and the like.

One preferable embodiment wherein a nucleic acid probe is immobilized on a solid phase is a DNA microarray. A DNA microarray can be produced by an Affymetrix method wherein a nucleic acid probe is synthesized by one nucleotide on a substrate (glass, silicon and the like), or a Stanford method wherein a nucleic acid probe prepared in advance is spotted on the substrate.

For quantitative analysis of the expression of a Macaca fascicularis -derived housekeeping gene using a trace amount of an RNA sample, competitive RT-PCR or real-time RT-PCR is preferably used. Competitive RT-PCR refers to a method including performing a competitive amplification reaction in the presence of, as a competitor, a known amount of other template nucleic acid that can be amplified by a set of primers capable of amplifying the objective DNA in the reaction mixture, and calculating the amount of the objective DNA by comparing the amounts of amplified products. When competitive RT-PCR is employed, therefore, the reagent of the present invention can further contain, in addition to the above-mentioned primer set, a nucleic acid which is amplified by the primer set to produce an amplification product (e.g., amplification product different from the object DNA in size, amplification product different from the object DNA in migration pattern by a restriction enzyme treatment and the like) that can be distinguished from the object DNA. The competitor nucleic acid may be a DNA or an RNA. In the case of DNA, PCR can be performed with addition of a competitor after synthesizing cDNA from an RNA sample by a reverse transcription reaction, and in the case of RNA, RT-PCR is performed with addition of a competitor to an RNA sample from the start. In the latter case, since the efficiency of the reverse transcription reaction is also taken into consideration, an absolute amount of the original mRNA can be assumed.

In contrast, since real-time RT-PCR permits real-time monitoring of amplification amount by PCR, electrophoresis is not necessary and the expression of a Macaca fascicularis -derived housekeeping gene can be analyzed more rapidly. Generally, monitoring is performed using various fluorescent reagents. Among them are a reagent that binds to double stranded DNA to emit fluorescence (intercalator) such as SYBR Green I, ethidium bromide and the like, as well as a nucleic acid that can be used as the above-mentioned probe (the nucleic acid hybridizes to a target nucleic acid within an amplification region) with one end modified by a fluorescent substance (e.g., FAM, HEX, TET, FITC etc.) and the other end by a quenching substance (e.g., TAMRA, DABCYL etc.) and the like.

The present invention also provides a method of analyzing the expression of Macaca fascicularis gene, which comprises measuring a gene transcription product in a Macaca fascicularis -derived sample using one or more kinds of the above-mentioned gene analysis tool of the present invention.

For example, the gene analysis tool of the present invention can be used for detection identification of a disease marker gene, a pharmacological action marker gene or a pharmaceutical agent toxicity marker gene using a cell-containing sample collected from Macaca fascicularis which is a disease model or Macaca fascicularis administered with a pharmaceutical agent, or isolated Macaca fascicularis cell or tissue exposed to a pharmaceutical agent (including culture and established cell line derived therefrom) and the like, and further preferably used for the analyses of disease mechanism, pharmacological action mechanism, toxicity action mechanism and the like.

Examples of the cell-containing sample taken from Macaca fascicularis include any cells [for example, hepatocyte, splenocyte, nerve cells, glial cell, pancreatic β cell, bone marrow cell, mesangial cell, Langerhans cell, epidermal cell, epithelial cells, goblet cell, endothelial cell, smooth muscle cell, fibroblast, fibrocyte, muscle cell, adipocyte, immune cell (e.g., macrophage, T cell, B cell, natural killer cell, mast cell, neutrophil, basophil, eosinophils, monocyte), megakaryocyte, synovial cell, chondrocyte, osteocyte, osteoblast, osteoclast, mammary cell, interstitial cell, or precursor cell, stem cell or cancer cell of these cells and the like] or any tissue in which such cells are present [e.g., brain, each part of brain (e.g., olfactory bulb, amygdaloid nucleus, basal ganglia, hippocampus, thalamus, hypothalamus, cerebral cortex, medulla oblongata, cerebellum), spinal cord, eyeball, pituitary gland, stomach, pancreas, kidney, liver, gonad, thyroid gland, gall bladder, bone marrow, adrenal gland, skin, lung, gastrointestinal tract (e.g., large intestine, small intestine), blood vessel, heart, thymus, spleen, submandibular gland, peripheral blood, prostate, orchis, ovary, placenta, uterus, bone, articular, adipose tissue, skeletal muscle and the like] and the like. Among these, blood (e.g., peripheral blood), lymphocyte and the like are preferable since they can be collected rapidly and conveniently and are less-invasive to animals, and the like.

Examples of the isolated Macaca fascicularis cell or tissue to be expose to a pharmaceutical agent include those similar to the above-mentioned, a primary culture or a passage culture thereof, or a cell line established from the above-mentioned cell•tissue, and the like can be mentioned. For good reproducibility and easy availability, and the like, cell lines are preferably used.

Gene expression in a cell-containing sample taken from Macaca fascicularis or a sample of isolated Macaca fascicularis cell or tissue exposed to a pharmaceutical agent can be examined by preparing an RNA (e.g., total RNA, mRNA) fraction from the sample, and detecting a transcription product of the marker gene in the fraction. While an RNA fraction can be prepared by a known means such as guanidine-CsCl ultracentrifugation method, AGPC method and the like, total RNA with high purity can be prepared rapidly and conveniently from a trace amount of a sample using a commercially available RNA extraction kit (e.g., RNeasy Mini Kit; QIAGEN etc.). As a means of detecting a gene transcription product in an RNA fraction, for example, a method using hybridization (Northern blot, dot blot, DNAchip (microarray) analysis etc.), a method using PCR (RT-PCR, competitive PCR, real-time PCR etc.) and the like can be mentioned. Quantitative PCRs such as competitive PCR, real-time PCR and the like are preferable since changes in the gene expression can be detected rapidly and conveniently with good quantifiability from a trace amount of a sample, and DNA chip (microarray) analysis is preferable since changes in the expression of a plurality of marker genes can be simultaneously detected and quantifiability can be improved by the selection of the detection method and the like.

When Northern blot or dot blot hybridization is performed, gene expression can be detected by using the above-mentioned gene analysis tool of the present invention containing nucleic acid(s) to be used as a labeled probe. Namely, in the case of Northern hybridization, an RNA fraction prepared as mentioned above is separated by gel electrophoresis, transferred to a membrane of nitrocellulose, nylon, polyvinylidene difluoride and the like, subjected to hybridization in a hybridization buffer containing the reagent of the present invention or each reagent in the kit of the present invention under the above-mentioned “highly stringent conditions”, and the amount of the labels bound to the membrane is measured for each band by a suitable method, whereby the expression level of each gene can be measured. Also in the case of dot blot, an RNA fraction spotted on a membrane is subjected to a hybridization reaction in the same manner (performed for each gene), and the amount of the labels of the spot is measured, whereby the expression level of each gene can be measured.

In the case of DNA chip (microarray) analysis, for example, cDNA with a suitable promoter such as T7 promoter introduced is synthesized by a reverse transcription reaction from an RNA fraction prepared as mentioned above, and then cRNA is synthesized using RNA polymerase (labeled cRNA can be obtained by using, as a substrate, mononucleotide labeled with biotin and the like at this point). The labeled cRNA is contacted with the above-mentioned solid phased probe to perform a hybridization reaction, and the amount of the labels bound to each probe on the solid phase is measured, whereby the expression level of each gene can be measured. The method is advantageous in terms of rapidness and convenience as the number of genes to be detected (accordingly, probes to be solid phased) increases.

Abbreviations for bases, amino acids and the like used in the present description are based on abbreviations specified by the IUPAC-IUB Commission on Biochemical Nomenclature or abbreviations in common use in relevant fields, some examples of which are given below. When an optical isomer may be present in amino acid, it is of the L-configuration, unless otherwise stated.

DNA: deoxyribonucleic acid

cDNA: complementary deoxyribonucleic acid

A: adenine

T: thymine

G: guanine

C: cytosine

RNA: ribonucleic acid

mRNA: messenger ribonucleic acid

dATP: deoxyadenosine triphosphate

dTTP: deoxythymidine triphosphate

dGTP: deoxyguanosine triphosphate

dCTP: deoxycytidine triphosphate

ATP: adenosine triphosphate

EDTA: ethylenediaminetetraacetic acid

SDS: sodium dodecyl sulfate

The SEQ ID NOs in the Sequence Listing in the present specification show the following sequences.

SEQ ID NO: 1: base sequence of Macaca fascicularis -derived GAPDH gene product fragment

SEQ ID NO: 2: base sequence of Macaca fascicularis -derived ACTB gene product fragment

SEQ ID NO: 3: base sequence of Macaca fascicularis -derived SDHA gene product fragment

SEQ ID NO: 4: base sequence of Macaca fascicularis -derived RPL4 gene product fragment

SEQ ID NO: 5: base sequence of Macaca fascicularis -derived TBP gene product fragment

SEQ ID NO: 6: base sequence of Macaca fascicularis -derived HPRT1 gene product fragment

SEQ ID NO: 7: base sequence of Macaca fascicularis -derived PPIA gene product fragment

SEQ ID NO: 8: base sequence of Macaca fascicularis -derived EEF1G gene product fragment

SEQ ID NO: 9: base sequence of Macaca fascicularis -derived PAPSS2 gene product fragment

SEQ ID NO: 10: base sequence of Macaca fascicularis -derived PGK1 gene product fragment

SEQ ID NO: 11: base sequence of Macaca fascicularis -derived TFRC gene product fragment

SEQ ID NO: 12: base sequence of Macaca fascicularis -derived GUSB gene product fragment

SEQ ID NO: 13: base sequence of Macaca fascicularis -derived B2M gene product fragment

SEQ ID NO: 14: base sequence of Macaca fascicularis -derived UBC gene product fragment

The present invention is explained in more detail in the following by referring to the Examples, which are mere exemplifications and do not limit the scope of the present invention in any way.

The gene expression analysis tool of the present invention can analyze gene expression of Macaca fascicularis quantitatively with high accuracy, since it contains nucleic acid(s) capable of detecting expression of at least two kinds of housekeeping genes derived from Macaca fascicularis . The tool is utilized for the search of a marker gene relating to the toxicity, pharmacological action and disease, as well as analysis of the mechanisms thereof, and is useful for the research and development of pharmaceutical product candidate compounds and the like.

This application is based on a patent application No. 2006-019858 filed in Japan, the contents of which are incorporated in full herein by this reference.