Abstract
In monogenic diseases, the presence of several sequence variations in the same allele may complicate our understanding of genotype–phenotype relationships. We described new alterations identified in a cystic fibrosis (CF) patient harboring a 48C>G promoter sequence variation associated in cis of a 3532AC>GTA mutation and in trans with the F508del mutation. Functional analyses including in vitro experiments confirmed the deleterious effect of the 3532GTA frameshift mutation through the creation of a premature termination codon. The analyses also revealed that the 48G promoter variant has a negative effect on both transcription and mRNA level, thus demonstrating the importance of analyzing all mutations or sequence variations with potential impact on CF transmembrane conductance regulator processing, even when the two known disease-causing mutations have already been detected. Our results emphasize the need to perform, wherever possible, functional studies that may greatly assist the interpretation of the disease-causing potential of rare mutation-associated sequence variations.
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References
O’Sullivan BP, Freedman SD : Cystic fibrosis. Lancet 2009; 373: 1891–1904.
Chmiel JF, Davis PB : State of the art: why do the lungs of patients with cystic fibrosis become infected and why can’t they clear the infection? Respir Res 2003; 4: 8.
Bartoszewski RA, Jablonsky M, Bartoszewska S et al: A synonymous single nucleotide polymorphism in DeltaF508 CFTR alters the secondary structure of the mRNA and the expression of the mutant protein. J Biol Chem 2010; 285: 28741–28748.
Pagani F, Raponi M, Baralle FE : Synonymous mutations in CFTR exon 12 affect splicing and are not neutral in evolution. Proc Natl Acad Sci USA 2005; 102: 6368–6372.
Taulan M, Lopez E, Guittard C et al: First functional polymorphism in CFTR promoter that results in decreased transcriptional activity and Sp1/USF binding. Biochem Biophys Res Commun 2007; 361: 775–781.
Lopez E, Viart V, Guittard C et al: Variants in CFTR untranslated regions are associated with congenital bilateral absence of the vas deferens. J Med Genet 2011; 48: 152–159.
Kiesewetter S, Macek Jr M, Davis C et al: A mutation in CFTR produces different phenotypes depending on chromosomal background. Nat Genet 1993; 5: 274–278.
Romey MC, Guittard C, Carles S, Demaille J, Claustres M, Ramsay M : First putative sequence alterations in the minimal CFTR promoter region. J Med Genet 1999; 36: 263–264.
Romey MC, Tuffery S, Desgeorges M, Bienvenu T, Demaille J, Claustres M : Transcript analysis of CFTR frameshift mutations in lymphocytes using the reverse transcription-polymerase chain reaction technique and the protein truncation test. Hum Genet 1996; 98: 328–332.
Disset A, Michot C, Harris A, Buratti E, Claustres M, Tuffery-Giraud S : A T3 allele in the CFTR gene exacerbates exon 9 skipping in vas deferens and epididymal cell lines and is associated with Congenital Bilateral Absence of Vas Deferens (CBAVD). Hum Mutat 2005; 25: 72–81.
Du K, Sharma M, Lukacs GL : The DeltaF508 cystic fibrosis mutation impairs domain-domain interactions and arrests post-translational folding of CFTR. Nat Struct Mol Biol 2005; 12: 17–25.
Kleizen B, van Vlijmen T, de Jonge HR, Braakman I : Folding of CFTR is predominantly cotranslational. Mol Cell 2005; 20: 277–287.
Gaboli M, Kotsi PA, Gurrieri C et al: Mzf1 controls cell proliferation and tumorigenesis. Genes Dev 2001; 15: 1625–1630.
Shiraga T, Winpenny JP, Carter EJ, McCarthy VA, Hollingsworth MA, Harris A : MZF-1 and DbpA interact with DNase I hypersensitive sites that correlate with expression of the human MUC1 mucin gene. Exp Cell Res 2005; 308: 41–52.
Ulatowski LM, Whitmore KL, Romigh T, VanderWyden AS, Satinover SM, Drumm ML : Strain-specific variants of the mouse Cftr promoter region reveal transcriptional regulatory elements. Hum Mol Genet 2004; 13: 1933–1941.
van den Heuvel S, Dyson NJ : Conserved functions of the pRB and E2F families. Nat Rev Mol Cell Biol 2008; 9: 713–724.
Chen HZ, Tsai SY, Leone G : Emerging roles of E2Fs in cancer: an exit from cell cycle control. Nat Rev Cancer 2009; 9: 785–797.
Lantinga-van Leeuwen IS, Leonhard WN, Dauwerse H et al: Common regulatory elements in the polycystic kidney disease 1 and 2 promoter regions. Eur J Hum Genet 2005; 13: 649–659.
Azizkhan JC, Jensen DE, Pierce AJ, Wade M : Transcription from TATA-less promoters. dihydrofolate reductase as a model. Crit Rev Eukaryot Gene Expr 1993; 3: 229–254.
Li H, Liu H, Wang Z et al: The role of transcription factors Sp1 and YY1 in proximal promoter region in initiation of transcription of the mu opioid receptor gene in human lymphocytes. J Cell Biochem 2008; 104: 237–250.
Lin SY, Black AR, Kostic D, Pajovic S, Hoover CN, Azizkhan JC : Cell cycle-regulated association of E2F1 and Sp1 is related to their functional interaction. Mol Cell Biol 1996; 16: 1668–1675.
Gill G, Pascal E, Tseng ZH, Tjian R : A glutamine-rich hydrophobic patch in transcription factor Sp1 contacts the dTAFII110 component of the Drosophila TFIID complex and mediates transcriptional activation. Proc Natl Acad Sci USA 1994; 91: 192–196.
Pearson A, Greenblatt J : Modular organization of the E2F1 activation domain and its interaction with general transcription factors TBP and TFIIH. Oncogene 1997; 15: 2643–2658.
Smale ST : Core promoters: active contributors to combinatorial gene regulation. Genes Dev 2001; 15: 2503–2508.
Liu WL, Coleman RA, Ma E et al: Structures of three distinct activator-TFIID complexes. Genes Dev 2009; 23: 1510–1521.
Riordan JR, Rommens JM, Kerem B et al: Identification of the cystic fibrosis gene: cloning and characterization of complementary DNA. Science 1989; 245: 1066–1073.
White NL, Higgins CF, Trezise AE : Tissue-specific in vivo transcription start sites of the human and murine cystic fibrosis genes. Hum Mol Genet 1998; 7: 363–369.
Acknowledgements
This work was supported by the French association Vaincre La Mucoviscidose, by PhD fellowships grants to VV (G0804), the Hospital of Montpellier (Centre Hospitalo-Universitaire) and the Institut National de la Santé et de la Recherche Médicale.
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Viart, V., Georges, M., Claustres, M. et al. Functional analysis of a promoter variant identified in the CFTR gene in cis of a frameshift mutation. Eur J Hum Genet 20, 180–184 (2012). https://doi.org/10.1038/ejhg.2011.161
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DOI: https://doi.org/10.1038/ejhg.2011.161


