title: Functional validation of mouse tyrosinase non-coding regulatory DNA elements by CRISPR-Cas9-mediated mutagenesis.
abstract: Newly developed genome-editing tools, such as the clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 system, allow simple and rapid genetic modification in most model organisms and human cell lines. Here, we report the production and analysis of mice carrying the inactivation via deletion of a genomic insulator, a key non-coding regulatory DNA element found 5' upstream of the mouse tyrosinase (Tyr) gene. Targeting sequences flanking this boundary in mouse fertilized eggs resulted in the efficient deletion or inversion of large intervening DNA fragments delineated by the RNA guides. The resulting genome-edited mice showed a dramatic decrease in Tyr gene expression as inferred from the evident decrease of coat pigmentation, thus supporting the functionality of this boundary sequence in vivo, at the endogenous locus. Several potential off-targets bearing sequence similarity with each of the two RNA guides used were analyzed and found to be largely intact. This study reports how non-coding DNA elements, even if located in repeat-rich genomic sequences, can be efficiently and functionally evaluated in vivo and, furthermore, it illustrates how the regulatory elements described by the ENCODE and EPIGENOME projects, in the mouse and human genomes, can be systematically validated.
authors.affiliation: Department of Molecular and Cellular Biology, National Centre for Biotechnology (CNB-CSIC), Campus Cantoblanco, Darwin 3, 28049 Madrid, Spain CIBERER-ISCIII, Madrid, Spain.
authors.forename: Davide
authors.initials: D
authors.lastname: Seruggia
authors.affiliation: Department of Molecular and Cellular Biology, National Centre for Biotechnology (CNB-CSIC), Campus Cantoblanco, Darwin 3, 28049 Madrid, Spain CIBERER-ISCIII, Madrid, Spain.
authors.forename: Almudena
authors.initials: A
authors.lastname: Fernández
authors.affiliation: Department of Molecular and Cellular Biology, National Centre for Biotechnology (CNB-CSIC), Campus Cantoblanco, Darwin 3, 28049 Madrid, Spain CIBERER-ISCIII, Madrid, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Cantero
authors.affiliation: Institute of Laboratory Animal Science, University of Zurich, Zurich, Switzerland.
authors.forename: Pawel
authors.initials: P
authors.lastname: Pelczar
authors.affiliation: Department of Molecular and Cellular Biology, National Centre for Biotechnology (CNB-CSIC), Campus Cantoblanco, Darwin 3, 28049 Madrid, Spain CIBERER-ISCIII, Madrid, Spain montoliu@cnb.csic.es.
authors.forename: Lluis
authors.initials: L
authors.lastname: Montoliu
mesh_terms: D000818:Animals; D064130:CRISPR-Associated Proteins / Q000378:metabolism; D064113:CRISPR-Cas Systems; D007446:Chromosome Inversion; D053903:DNA Breaks, Double-Stranded; D003851:Deoxyribonucleases / Q000378:metabolism; D038101:Insulator Elements; D051379:Mice; D008822:Mice, Transgenic; D014442:Monophenol Monooxygenase / Q000235:genetics*; D016296:Mutagenesis; D010858:Pigmentation / Q000235:genetics; D017384:Sequence Deletion
chemical_list: D064130:CRISPR-Associated Proteins; D014442:Monophenol Monooxygenase; D003851:Deoxyribonucleases