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de Cian, A.

Publications and source records attributed to de Cian, A..

3 recordsLinked to original sources

Rearrangement of chromosome spatial organization in mouse zygotes using optical tweezers does not affect preimplantation development

The spatial arrangement of chromosomes is thought to influence key processes such as gene expression or chromosome segregation. However, the contribution of chromosome spatial organization in physiological contexts remains disputed. Here, we use optical tweezers to displace nucleoli and physically rearrange the nuclear contents of mouse zygotes. Monitoring the preimplantation development of zygotes with physically shuffled nuclei reveals that cell dynamics, gene expression and overall blastocyst formation are not affected. This suggests that in mouse zygotes, the spatial organisation of chromosomes is not critical for blastocyst development.

developmental biology↗

CRISPR-Cas9 mediated endogenous utrophin upregulation improves Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is a lethal neuromuscular disorder caused by loss of dystrophin. Upregulation of utrophin (UTRN), a dystrophin paralogue, is a promising therapeutic avenue. Here, we present a CRISPR-Cas9-mediated strategy to increase utrophin expression by disrupting microRNA (miR) binding sites (BS). Using a Cas9/gRNA ribonucleoprotein (RNP) complex we disrupted several miR BS in DMD myoblasts and selected the Let-7c BS has crucial for UTRN repression. Interestingly, Cas9/gRNA indels were as efficient as the complete removal of Let-7c BS in upregulating UTRN expression, without any major off-targets. In three-dimensional human DMD cultures, Cas9/gRNA-mediated editing resulted in significant utrophin upregulation and functional improvements of calcium dysregulation and muscle contraction. Finally, Let-7c BS disruption in mdx animals by systemic rAAVs mediated delivery of Cas9 and gRNA resulted in utrophin upregulation and amelioration of the muscle histopathological phenotype. These findings provide the foundations for a universal (mutation-independent) gene editing therapeutic strategy for DMD. One Sentence SummaryCRISPR-Cas9 has the potential to upregulate utrophin to treat all DMD patients.

molecular biology↗

A novel lineage of candidate pheromone receptors for sex communication in moths

Sex pheromone receptors (PRs) are key players in chemical communication between mating partners in insects. In the highly diversified insect order Lepidoptera, male PRs tuned to female-emitted type I pheromones (which make up the vast majority of pheromones identified) form a dedicated subfamily of odorant receptors (ORs). Here, using a combination of heterologous expression and in vivo genome editing methods, we bring functional evidence that at least one moth PR does not belong to this subfamily but to a distantly related OR lineage. This PR, identified in the cotton leafworm Spodoptera littoralis, is over-expressed in male antennae and is specifically tuned to the major sex pheromone component emitted by females. Together with a comprehensive phylogenetic analysis of moth ORs, our functional data suggest two independent apparitions of PRs tuned to type I pheromones in Lepidoptera, opening up a new path for studying the evolution of moth pheromone communication.

evolutionary biology↗