title: A systematic analysis of the 3'UTR of HNF4A mRNA reveals an interplay of regulatory elements including miRNA target sites.
abstract: Dysfunction of hepatocyte nuclear factor 4α (HNF4α) has been linked to maturity onset diabetes of the young (MODY1), diabetes type II and possibly to renal cell carcinoma (RCC). Whereas diabetes causing mutations are well known, there are no HNF4A mutations found in RCC. Since so far analyses have been constricted to the promoter and open reading frame of HNF4A, we performed a systematic analysis of the human HNF4A 3'UTR. We identified a short (1724 nt) and long (3180 nt) 3'UTR that are much longer than the open reading frame and conferred a repressive effect in luciferase reporter assays in HEK293 and INS-1 cells. By dissecting the 3'UTR into several pieces, we located two distinct elements of about 400 nt conferring a highly repressive effect. These negative elements A and B are counteracted by a balancer element of 39 nt located within the 5' end of the HNF4A 3'UTR. Dicer knock-down experiments implied that the HNF4A 3'UTR is regulated by miRNAs. More detailed analysis showed that miR-34a and miR-21 both overexpressed in RCC cooperate in downregulation of the HNF4A mRNA. One of the identified miR-34a binding sites is destroyed by SNP rs11574744. The identification of several regulatory elements within the HNF4A 3'UTR justifies the analysis of the 3'UTR sequence to explore the dysfunction of HNF4α in diabetes and RCC.
authors.affiliation: Institut für Zellbiologie (Tumorforschung), Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Wirsing
authors.forename: Sabine
authors.initials: S
authors.lastname: Senkel
authors.forename: Ludger
authors.initials: L
authors.lastname: Klein-Hitpass
authors.forename: Gerhart U
authors.initials: GU
authors.lastname: Ryffel
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics*; D001483:Base Sequence; D001665:Binding Sites; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D017930:Genes, Reporter / Q000235:genetics; D057809:HEK293 Cells; D051557:Hepatocyte Nuclear Factor 4 / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D026723:Polyadenylation / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D043244:Ribonuclease III / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; C496592:HNF4A protein, human; D051557:Hepatocyte Nuclear Factor 4; C524940:MIRN21 microRNA, human; C522425:MIRN34 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D043244:Ribonuclease III