title: Quantitative measurement of spliced XBP1 mRNA as an indicator of endoplasmic reticulum stress.
abstract: The unfolded protein response (UPR) events triggered by the accumulation of unfolded protein in endoplasmic reticulum (ER) activate the three UPR signaling pathways mediated by IRE1, ATF6 and PERK. Spliced XBP1 mRNA induced by activated IRE1 is translated to the protein, a potent transcription factor that induces BiP expression. XBP1 is also induced by activated ATF6. It is thus thought to be an important marker reflecting both IRE1 and ATF6 signaling in response to ER stress. For quantitative measurement of XBP1 gene expression, it is important to distinguish between the spliced and non-spliced form of XBP1 mRNA. We have developed a new method to detect the spliced XBP1 mRNA by means of real-time PCR and we compared the result with measurements of the expression of the ER stress inducible gene BiP. A good correlation was found between spliced XBP1 expression and BiP expression. Thus, our method may be useful for simple and quantitative evaluation of ER stress.
authors.affiliation: Shiseido Research Center, 2-11-1 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-8643, Japan. morihiko.hirota@to.shiseido.co.jp
authors.forename: Morihiko
authors.initials: M
authors.lastname: Hirota
authors.forename: Masato
authors.initials: M
authors.lastname: Kitagaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Itagaki
authors.forename: Setsuya
authors.initials: S
authors.lastname: Aiba
mesh_terms: D051702:Activating Transcription Factor 6 / Q000378:metabolism; D002478:Cells, Cultured; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000235:genetics*; D004229:Dithiothreitol / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000235:genetics* / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP; D004722:Endoribonucleases / Q000378:metabolism; D015870:Gene Expression; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D018832:Molecular Chaperones / Q000378:metabolism; D008969:Molecular Sequence Data; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics*; D021141:Nucleic Acid Amplification Techniques; D018384:Oxidative Stress; D017510:Protein Folding; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D012326:RNA Splicing; D012333:RNA, Messenger / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D000071701:Regulatory Factor X Transcription Factors; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D015398:Signal Transduction; D014157:Transcription Factors; D000071717:X-Box Binding Protein 1; D019892:eIF-2 Kinase / Q000378:metabolism
chemical_list: D051702:Activating Transcription Factor 6; D017931:DNA Primers; D004268:DNA-Binding Proteins; D004229:Dithiothreitol; D000091342:Endoplasmic Reticulum Chaperone BiP; D004722:Endoribonucleases; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D017346:Protein Serine-Threonine Kinases; D012333:RNA, Messenger; D000071701:Regulatory Factor X Transcription Factors; D014157:Transcription Factors; D000071717:X-Box Binding Protein 1; D019892:eIF-2 Kinase; C497111:ATF6 protein, human; C000605543:XBP1 protein, human; C403982:ERN2 protein, human