In vivo labeling of endogenous genomic loci in C. elegans using CRISPR/dCas9

Nadin Memar; Aditya Sethi; Sebastian Luehr; Eric J Lambie; Barbara Conradt

doi:10.17912/micropub.biology.000701

In vivo labeling of endogenous genomic loci in C. elegans using CRISPR/dCas9

MicroPubl Biol. 2022 Dec 13:2022:10.17912/micropub.biology.000701. doi: 10.17912/micropub.biology.000701. eCollection 2022.

Authors

Nadin Memar^#¹, Aditya Sethi^#², Sebastian Luehr³, Eric J Lambie², Barbara Conradt²

Affiliations

¹ Institute for Basic Science (IBS), Ulsan 44919, South Korea.
² University College London, United Kingdom.
³ Ludwig-Maximilians-University Munich, Germany.

^# Contributed equally.

Abstract

Visualization of genomic loci with open chromatin state has been reported in mammalian tissue culture cells using a CRISPR/Cas9-based system that utilizes an EGFP-tagged endonuclease-deficient Cas9 protein (dCas9::EGFP) (Chen et al. 2013). Here, we adapted this approach for use in Caenorhabditis elegans . We generated a C. elegans strain that expresses the dCas9 protein fused to two nuclear-localized EGFP molecules (dCas9::NLS::2xEGFP::NLS) in an inducible manner. Using this strain, we report the visualization in live C. elegans embryos of two endogenous repetitive loci, rrn-4 and rrn-1 , from which 5S and 18S ribosomal RNAs are constitutively generated.