title: Impact of adenoviral transduction with SREBP1c or AMPK on pancreatic islet gene expression profile: analysis with oligonucleotide microarrays.
abstract: Accumulation of triglyceride in islets may contribute to the loss of glucose-stimulated insulin secretion (GSIS) in some forms of type 2 diabetes (Diraison et al., Biochem J 373:769-778, 2004). Here, we use adenoviral vectors and oligonucleotide microarrays to determine the effects of the forced expression of SREBP1c on the gene expression profile of rat islets. Sterol regulatory element binding protein-1c (SREBP1c) overexpression led to highly significant (P <0.1 with respect to null adenovirus) changes in the expression of 1,238 genes or expressed sequence tags, of which 1,180 (95.3%) were upregulated. By contrast, overexpression of constitutively active AMP-activated protein kinase (AMPK), expected to promote lipolysis, altered the expression of 752 genes, of which 702 (93%) were upregulated. To identify specific targets for SREBP1c or AMPK, we eliminated messages that were 1) affected in the same direction by the expression of either protein, 2) changed by less than twofold, or 3) failed a positive false discovery test; 206 SREBP1c-regulated genes (195; 95% upregulated) and 48 AMPK-regulated genes (33; 69% upregulated) remained. As expected, SREBP1c-induced genes included those involved in cholesterol (6), fatty acid (3), and eicosanoid synthesis. Interestingly, somatostatin receptor (sstr1) expression was increased by SREBP1c, whereas AMPK induced the expression of peptide YY, the early endocrine pancreas marker.
authors.affiliation: Henry Wellcome Signalling Laboratories and Department of Biochemistry, School of Medical Sciences, University Walk, University of Bristol, Bristol, BS8 ITD, UK.
authors.forename: Frederique
authors.initials: F
authors.lastname: Diraison
authors.forename: Efthimios
authors.initials: E
authors.lastname: Motakis
authors.forename: Laura E
authors.initials: LE
authors.lastname: Parton
authors.forename: Guy P
authors.initials: GP
authors.lastname: Nason
authors.forename: Isabelle
authors.initials: I
authors.lastname: Leclerc
authors.forename: Guy A
authors.initials: GA
authors.lastname: Rutter
mesh_terms: D000256:Adenoviridae; D000263:Adenylate Kinase / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D022762:CCAAT-Enhancer-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D020224:Expressed Sequence Tags; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007515:Islets of Langerhans / Q000502:physiology*; D016350:Leucine Zippers; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; C497389:Srebf1 protein, rat; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors; D000263:Adenylate Kinase