title: Trinucleotide Repeat Expansion in the Transcription Factor 4 (TCF4) Gene Leads to Widespread mRNA Splicing Changes in Fuchs' Endothelial Corneal Dystrophy.
abstract: To identify RNA missplicing events in human corneal endothelial tissue isolated from Fuchs' endothelial corneal dystrophy (FECD).
  
  
  
  Total RNA was isolated and sequenced from corneal endothelial tissue obtained during keratoplasty from 12 patients with FECD and 4 patients undergoing keratoplasty or enucleation for other indications. The length of the trinucleotide repeat (TNR) CTG in the transcription factor 4 (TCF4) gene was determined using leukocyte-derived DNA analyzed by a combination of Southern blotting and Genescan analysis. Commercial statistical software was used to quantify expression of alternatively spliced genes. Validation of selected alternative splicing events was performed by using RT-PCR. Gene sets identified were analyzed for overrepresentation using Web-based analysis system.
  
  
  
  Corneal endothelial tissue from FECD patients containing a CTG TNR expansion sequence in the TCF4 gene revealed widespread changes in mRNA splicing, including a novel splicing event involving FGFR2. Differential splicing of NUMA1, PPFIBP1, MBNL1, and MBNL2 transcripts were identified in all FECD samples containing a TNR expansion. The differentially spliced genes were enriched for products that localize to the cell cortex and bind cytoskeletal and cell adhesion proteins.
  
  
  
  Corneal endothelium from FECD patients harbors a unique signature of mis-splicing events due to CTG TNR expansion in the TCF4 gene, consistent with the hypothesis that RNA toxicity contributes to the pathogenesis of FECD. Changes to the endothelial barrier function, a known event in the development of FECD, was identified as a key biological process influenced by the missplicing events.
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Wieben
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Ross A
authors.initials: RA
authors.lastname: Aleff
authors.affiliation: Division of Biostatistics and Bioinformatics and Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Xiaojia
authors.initials: X
authors.lastname: Tang
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Malinda L
authors.initials: ML
authors.lastname: Butz
authors.affiliation: Division of Biostatistics and Bioinformatics and Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Krishna R
authors.initials: KR
authors.lastname: Kalari
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Edward W
authors.initials: EW
authors.lastname: Highsmith
authors.affiliation: Department of Experimental Pathology and Laboratory Medicine, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Jin
authors.initials: J
authors.lastname: Jen
authors.affiliation: Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: George
authors.initials: G
authors.lastname: Vasmatzis
authors.affiliation: Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Sanjay V
authors.initials: SV
authors.lastname: Patel
authors.affiliation: Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Leo J
authors.initials: LJ
authors.lastname: Maguire
authors.affiliation: Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Keith H
authors.initials: KH
authors.lastname: Baratz
authors.affiliation: Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Fautsch
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015139:Blotting, Southern; D004728:Endothelium, Corneal / Q000378:metabolism / Q000473:pathology; D005260:Female; D005642:Fuchs' Endothelial Dystrophy / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012326:RNA Splicing / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D000073940:Transcription Factor 4; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D019680:Trinucleotide Repeat Expansion
chemical_list: D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D012333:RNA, Messenger; C532096:TCF4 protein, human; D000073940:Transcription Factor 4; D014157:Transcription Factors