Search bioRxiv⌕ Search

Biology subjects

Malaga-Trillo, E.

Publications and source records attributed to Malaga-Trillo, E..

2 recordsLinked to original sources

Comparison of robotic automated and manual injection methods in zebrafish embryos for high throughput RNA silencing using CRISPR-CasRx

Recently, the CRISPR-RfxCas13d (CasRx) system was proven to induce efficient mRNA knockdown in animal embryos. Here we compared the efficiency of CasRx-based RNA depletion with that of Cas9-mediated DNA targeting under the same conditions, using automated robotic and manual injection methods. As a proof-of-principle target, we used the no tail (tbxta) gene in zebrafish embryos, for which knockdown and knockout embryonic phenotypes were easy to be scored. Both Cas9 and CasRx systems induced loss of function phenotypes of tbxta gene. Higher percentage of severe phenotype was observed using Cas9 protein compared to the mRNA while the efficiency was similar in terms of Cas13d protein and mRNA. In addition, both the robotic and manual injection approaches yielded similar percentages of phenotypes and mortality rates. Therefore, our study not only showcases the potential of RNA-targeting CRISPR effectors for precise and potent gene knockdown, but also emphasizes automated microinjection in zebrafish embryos as an excellent alternative to manual methods for achieving gene knockdown at a high throughput level.

bioengineering↗

CRISPR-Cas13d induces efficient mRNA knock-down in animal embryos

Early embryonic development is driven exclusively by maternal gene products deposited into the oocyte. Although critical in establishing early developmental programs, maternal gene functions have remained elusive due to a paucity of techniques for their systematic disruption and assessment. CRISPR-Cas13 systems have recently been employed to induce RNA degradation in yeast, plants and mammalian cell lines. However, no systematic study of the potential of Cas13 has been carried out in an animal system. Here, we show that CRISPR-Cas13d is an effective and precise system to deplete specific mRNA transcripts in zebrafish embryos. We demonstrate that both zygotically-expressed and maternally-provided transcripts are efficiently targeted, resulting in an 80% average decrease in transcript level and the recapitulation of well-known embryonic phenotypes. Moreover, we show that this system can be used in medaka, killifish and mouse embryos. Altogether our results demonstrate that CRISPR-Cas13d is an efficient knock-down platform to interrogate gene function in animal embryos.

developmental biology↗