Effect of the [CCTG]n repeat expansion on ZNF9 expression in myotonic dystrophy type II (DM2).
Myotonic dystrophy is caused by two different mutations: a (CTG)n expansion in 3' UTR region of the DMPK gene (DM1) and a (CCTG)n expansion in intron 1 of the ZNF9 gene (DM2). The most accredited mechanism for DM pathogenesis is an RNA gain-of-function. Other findings suggest a contributory role of DMPK-insufficiency in DM1. To address the issue of ZNF9 role in DM2, we have analyzed the effects of (CCTG)n expansion on ZNF9 expression in lymphoblastoid cell lines (n=4) from DM2 patients. We did not observe any significant alteration in ZNF9 mRNA and protein levels, as shown by QRT-PCR and Western blot analyses. Additional RT-PCR experiments demonstrated that ZNF9 pre-mRNA splicing pattern, which includes two isoforms, is unmodified in DM2 cells. Our results indicate that the (CCTG)n expansion in the ZNF9 intron does not appear to have a direct consequence on the expression of the gene itself.
Botta
Annalisa
A
Department of Biopathology, Tor Vergata University, Rome, Italy.
Caldarola
Sara
S
Vallo
Laura
L
Bonifazi
Emanuela
E
Fruci
Doriana
D
Gullotta
Francesca
F
Massa
Roberto
R
Novelli
Giuseppe
G
Loreni
Fabrizio
F
D001483:Base Sequence; D002478:Cells, Cultured; D042622:DNA Repeat Expansion; D005786:Gene Expression Regulation; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007438:Introns; D008214:Lymphocytes / Q000166:cytology / Q000502:physiology; D008969:Molecular Sequence Data; D009154:Mutation; D009223:Myotonic Dystrophy / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012322:RNA Precursors / Q000378:metabolism; D012326:RNA Splicing; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016335:Zinc Fingers
C433227:CNBP protein, human; D020033:Protein Isoforms; D012322:RNA Precursors; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins