Data on the generation of two Nr2e3 mouse models by CRISPR / Cas9D10A nickase

Abstract

NR2E3 encodes an orphan nuclear receptor that plays a dual function as both transcriptional activator and repressor in photoreceptors, being necessary for cone fate inhibition as well as rod differentiation and homeostasis. Mutations in this gene cause retinitis pigmentosa (RP), enhanced S cone syndrome (ESCS) and Goldmann-Favre syndrome (GFS). There is one reported Nr2e3 isoform that contains all 8 exons and a second –previously unreported– shorter isoform, which only spans the first 7 exons and whose function is still unknown. In this data article, we designed and generated two new mouse models by targeting exon 8 of Nr2e3 using the CRISPR/Cas9-D10A nickase in order to dissect the role of the two isoforms in Nr2e3 function and elucidate the different disease mechanisms caused by NR2E3 mutations. This strategy generated several modified alleles that altered the coding sequence of the last exon thereby affecting functional domains of the transcription factor. Allele Δ27 is an in-frame deletion of 27 bp that ablates the dimerization domain, whereas allele ΔE8 (full deletion of exon 8), produces only the short isoform that lacks the dimerization and repressor domains. Morphological and functional alterations of both Δ27 and ΔE8 mutants are reported in the associated research article “ Nr2e3 functional domain ablation by CRISPR-Cas9D10A identifies a new isoform and generated Retinitis Pigmentosa and Enhanced S-cone Syndrome models” (Aísa-Marín et al., 2020).

Efficient and safe therapeutic use of paired Cas9-nickases for primary hyperoxaluria type 1

“…The efficiency of paired nCas9 for precise mammalian genome editing has been characterized in vitro (Trevino and Zhang, 2014 ; Cho et al, 2014 ). It has also been employed in mouse zygotes for gene functionality research (Aísa-Marín et al, 2020 ; Shen et al, 2014 ) and the generation of animal models (Aísa-Marín et al, 2020 ; Domènech et al, 2020 ). In a recent study, hereditary tyrosinemia was successfully corrected in rats using a single nCas9 together with a homology template carried by two independent adenoviruses.…”

Loss of NR2E3 disrupts rod photoreceptor cell maturation causing a fate switch late in human retinal development

“…The Rd7 mouse harbors spontaneous mutations in Nr2e3, which cause a retinal degeneration phenotype reminiscent of the ESCS patients (Iannaccone et al, 2021). However, key rod function genes such as the light-sensitive protein rhodopsin (Rho) are expressed in the Nr2e3-deficient mouse retina (Aísa-Marín et al, 2023;4 Corbo and Cepko, 2005;Haider et al, 2006;Iannaccone et al, 2021), in contrast to the complete loss of rod function observed in ESCS patients. As the mouse has a rod-dominant retina lacking a conerich macula (Volland et al, 2015), and the requirement of core rod transcription factors for rod specification is known to vary in other vertebrates (Oel et al, 2020), the precise regulatory processes governing rod and cone photoreceptor specification and maturation may differ between species.…”

Specific photoreceptor cell fate pathways are differentially altered in NR2E3-associated diseases

“…We previously generated two Nr2e3 mouse models using CRISPR-Cas9 editing to delete different domains encoded in the last exon (Aísa-Marín et al, 2020b, 2020a. The Nr2e3 ∆27 model -carrying a homozygous in-frame deletion that ablates the dimerization domain-shows an ESCS-like phenotype, with profound but non-progressive alterations in retinal function (Aísa-Marín et al, 2020a).…”