CEL eidoscope: quad-fluorescent Caenorhabditis elegans strain for tissue-specific spectral single-cell analyses

Cell and tissue-specific transcriptomic profiling of Caenorhabditis elegans is commonly achieved by fluorescence tagging or staining of targeted cell populations, often followed by fluorescence-activated cell sorting (FACS) and RNA sequencing. However, these approaches typically require separate strains for each labeled population, increasing labor and experimental variability while limiting direct comparison of multiple tissues within the same genetic background. To address this limitation and establish proof of concept, we engineered CEL eidoscope, a multicolored C. elegans strain that enables spectral sorting of multiple major cell types within a single strain population. Strain construction was carried out using a high-throughput screening method that reduces the labor and plastic costs associated with transgene integration and outcrossing. Four primary tissues (body muscle, neurons, intestinal, and pharyngeal muscle cells) were tagged with spectrally distinct fluorescent proteins, allowing compatibility with viability and nucleic acid dyes. Using spectral flow cytometry, dissociated CEL eidoscope cell suspensions could be sorted based on their spectral profiles, with cell recovery rates approximating the expected cell counts in whole organisms. Transcriptomic analysis of the sorted cell populations further validated the identity of the sorted populations, with recovered cells exhibiting gene expression signatures consistent with their intended cell and tissue identities. Together, these results establish CEL eidoscope as a versatile tool for multiplexed cell-type isolation in C. elegans , providing a framework for tissue-specific analyses from a common strain background.