title: HHEX promotes hepatic-lineage specification through the negative regulation of eomesodermin.
abstract: Human embryonic stem cells (hESCs) could provide a major window into human developmental biology, because the differentiation methods from hESCs mimic human embryogenesis. We previously reported that the overexpression of hematopoietically expressed homeobox (HHEX) in the hESC-derived definitive endoderm (DE) cells markedly promotes hepatic specification. However, it remains unclear how HHEX functions in this process. To reveal the molecular mechanisms of hepatic specification by HHEX, we tried to identify the genes directly targeted by HHEX. We found that HHEX knockdown considerably enhanced the expression level of eomesodermin (EOMES). In addition, HHEX bound to the HHEX response element located in the first intron of EOMES. Loss-of-function assays of EOMES showed that the gene expression levels of hepatoblast markers were significantly upregulated, suggesting that EOMES has a negative role in hepatic specification from the DE cells. Furthermore, EOMES exerts its effects downstream of HHEX in hepatic specification from the DE cells. In conclusion, the present results suggest that HHEX promotes hepatic specification by repressing EOMES expression.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Watanabe
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan; Laboratory of Hepatocyte Differentiation, National Institute of Biomedical Innovation, Osaka, Japan; iPS Cell-Based Research Project on Hepatic Toxicity and Metabolism, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Takayama
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Inamura
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Tachibana
authors.affiliation: Laboratory of Hepatocyte Differentiation, National Institute of Biomedical Innovation, Osaka, Japan.
authors.forename: Natsumi
authors.initials: N
authors.lastname: Mimura
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Katayama
authors.affiliation: Laboratory of Stem Cell Regulation, National Institute of Biomedical Innovation, Osaka, Japan.
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Tashiro
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan; Laboratory of Hepatocyte Differentiation, National Institute of Biomedical Innovation, Osaka, Japan.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Nagamoto
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan.
authors.forename: Fuminori
authors.initials: F
authors.lastname: Sakurai
authors.affiliation: Laboratory of Stem Cell Regulation, National Institute of Biomedical Innovation, Osaka, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kawabata
authors.affiliation: Laboratory of Embryonic Stem Cell Cultures, Department of Disease Bioresources Research, National Institute of Biomedical Innovation, Osaka, Japan; Department of Embryonic Stem Cell Research, Field of Stem Cell Research, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.
authors.forename: Miho Kusuda
authors.initials: MK
authors.lastname: Furue
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan; Laboratory of Hepatocyte Differentiation, National Institute of Biomedical Innovation, Osaka, Japan; iPS Cell-Based Research Project on Hepatic Toxicity and Metabolism, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan; The Center for Advanced Medical Engineering and Informatics, Osaka University, Osaka, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Mizuguchi
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D019521:Body Patterning / Q000187:drug effects / Q000235:genetics; D055415:Bone Morphogenetic Protein 4 / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D019070:Cell Lineage / Q000187:drug effects / Q000235:genetics; D053595:Embryonic Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D004707:Endoderm / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D055785:Gene Knockdown Techniques; D006367:HeLa Cells; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000166:cytology*; D051379:Mice; D011485:Protein Binding / Q000187:drug effects / Q000235:genetics; D034741:RNA, Small Interfering / Q000378:metabolism; D020218:Response Elements / Q000235:genetics; D020825:T-Box Domain Proteins / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D015415:Biomarkers; D055415:Bone Morphogenetic Protein 4; C491199:EOMES protein, human; C078492:HHEX protein, human; D018398:Homeodomain Proteins; D034741:RNA, Small Interfering; D020825:T-Box Domain Proteins; D014157:Transcription Factors