title: Functional genetic dissection of nuclear receptor signalling in obesity, diabetes and liver regeneration using spatiotemporally controlled somatic mutagenesis in the mouse.
abstract: The mouse is an excellent animal model for defining human diseases. The null allele mutations (knockouts, KO) have already provided valuable information about their functions, but have also revealed major complications and difficulties: (1) an early embryonic lethality, (2) temporal effect (developmental stage or adult stage), (3) functional redundancy and (4) spatio-effect (cell-autonomous or non-autonomous). To overcome these limitations, spatio-temporally controlled somatic mutagenesis, Cre-ER(T)/LoxP system, was established. The nuclear receptors (NRs) play central roles in development, organogenesis, metabolism and energy homeostasis through their ability to transduce hormonal signals into modulation of gene activity. Obesity, excess energy storage in adipose tissue, has a strong link to diabetes. Among NRs, retinoid X receptor alpha (RXRalpha)-peroxisome proliferator-activated receptor gamma (PPARgamma) heterodimers can mediate adipocyte differentiation and obesity which has been demonstrated with in vitro cell culture systems and RXR- and PPARgamma-specific ligand studies. Therefore an adipocyte-specific temporally controlled somatic mutagenesis system was established and analysed. Furthermore, the functional roles of NRs to control liver regeneration were also studied with similar system in hepatocytes.
authors.affiliation: Department of Physiological Genetics of Nuclear Signalling, IGBMC, Illkirch, France. imai@igbmc.u-strasbg.fr
authors.forename: Takeshi
authors.initials: T
authors.lastname: Imai
mesh_terms: D017667:Adipocytes / Q000378:metabolism; D000818:Animals; D003920:Diabetes Mellitus / Q000235:genetics*; D004967:Estrogens / Q000378:metabolism; D005821:Genetic Techniques; D018095:Germ-Line Mutation; D022781:Hepatocytes / Q000166:cytology; D006801:Humans; D008024:Ligands; D008099:Liver / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D016296:Mutagenesis; D009765:Obesity / Q000235:genetics*; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D018168:Receptors, Retinoic Acid / Q000378:metabolism; D012038:Regeneration; D047488:Retinoid X Receptors; D015398:Signal Transduction; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D004967:Estrogens; D008024:Ligands; D018160:Receptors, Cytoplasmic and Nuclear; D018168:Receptors, Retinoic Acid; D047488:Retinoid X Receptors; D014157:Transcription Factors