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bioRxiv · 10.64898/2026.01.15.699741

Modular gene tagging in C. elegans

Hefel, A.·Kruse, K.·Wall, K.·Jorgensen, S. B.·Ng, K. H.·Stolley, R.·Rich, M. S.·Jorgensen, E. M.
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Abstract

Tagging a gene endogenously can identify when the gene is expressed and where the protein is localized. CRISPR is the primary tool for generating tags of endogenous genes, but it is error-prone and requires unique reagents for each gene and tag. Recombinases can insert DNA in an error-free and modular manner. Here, we tested eight recombinases for germline function in the nematode C. elegans, and introduce PhIT, a recombinase-based method for protein tagging. First, a short 39bp PhiC31 attB landing pad is inserted into the locus by CRISPR. This strain is a resource which can be used to insert a variety of modular tags. Second, tags are inserted by the integrase PhiC31, and in tandem, extraneous backbone sequences are removed by a tyrosine recombinase. Current modular tags include seven different fluorescent proteins, FLP-regulated cell-specific expression constructs, and degron tags. Importantly, tags can be inserted by genetic crosses instead of by microinjection.

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Hefel, A., Kruse, K., Wall, K., Jorgensen, S. B., Ng, K. H., Stolley, R., Rich, M. S., Jorgensen, E. M.. 2026-01-15. Modular gene tagging in C. elegans. https://doi.org/10.64898/2026.01.15.699741

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