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The C. elegans community has always emphasized the need for open science and collaboration. The field already has comprehensive reference pages and curated databases for scientists including Wormbook, Wormatlas and Wormbase. And scientists have been continuously sharing their worm strains through the Caenorhabditis Genetics Center (CGC) which maintains and distributes the strains all over the world.

When I was at the 22nd International C. elegans meeting, I was again reminded of the extent that C. elegans researchers embrace open science and share resources and tools. That message was fully exemplified in Cori Bargmann’s keynote speech and in the workshops on CRISPR techniques and new tools for conditional expression and degradation. These workshops not only highlighted new tools but also included time for questions and a group discussion on the best strategies and protocols for different experiments. 

In the summer of 2013, a remarkable nine papers describing CRISPR/Cas9 genome engineering methods for C. elegans were released, signaling a new era in C. elegans research. Homology directed repair (HDR), which enables insertion of custom genomic modifications, is very robust in C. elegans, and the methods for HDR-mediated modification continue to be improved. New work from Bob Goldstein’s lab at the University of North Carolina has made CRISPR in C. elegans even easier - now, one can generate a fluorescent protein fusion, transcriptional reporter, and loss-of-function allele in just one injection step! The entire protocol takes about 2-3 weeks but requires less than eight hours worth of hands-on time.

This post was contributed by Jordan Ward who is a postdoctoral fellow at UCSF.

Emerging CRISPR/Cas9 editing technologies have transformed the palette of experiments possible in a wide range of organisms and cell lines. In C. elegans, one of the model organisms which I use to study gene regulation during developmental processes, CRISPR/Cas9 allows us to knock out sequences and introduce mutations and epitopes with unprecedented ease. In the last year, several advances in C. elegans genome editing using CRISPR/Cas9 have emerged, which I will describe below. These new C. elegans approaches rapidly enrich for editing events without the need for any selective marker to remain in the edited animal. To my knowledge these approaches have not yet been extended to other organisms/cell lines, though it is likely that many aspects will broadly improve editing efficiency.