Transcriptomic profiling of the embryonic C. elegans intestine with single-cell resolution

Area of Science:

• Developmental Biology
• Genomics
• Cell Biology

Background:

• The Caenorhabditis elegans intestine, despite its small size (20 cells), performs critical functions including metabolism, energy homeostasis, host defense, and aging.
• Understanding the developmental processes and cellular heterogeneity within the embryonic intestine is crucial for deciphering its specialized functions.

Purpose of the Study:

• To investigate the spatiotemporal development of specialized functions in the Caenorhabditis elegans intestine.
• To identify and characterize distinct cell types and states within the embryonic intestine using single-cell RNA sequencing.

Main Methods:

• Single-cell RNA sequencing (scRNA-seq) was performed on FACS-enriched intestinal cells from mixed-stage C. elegans embryos.
• Transcriptomic data from 974 cells were analyzed to identify 13 distinct clusters.
• Spatial assignments were refined using smiFISH microscopy and marker gene expression along the anterior-posterior axis.

Main Results:

• Thirteen distinct cell clusters were identified, indicating significant cellular heterogeneity in the embryonic intestine.
• Early-stage clusters were associated with growth and cell division genes, while later-stage clusters showed genes for metabolism and immune responses.
• Genes involved in biotic responses and RNA metabolism varied along the anterior-posterior axis, with anterior-specific gene perturbations having a more significant functional impact.

Conclusions:

• The embryonic C. elegans intestine exhibits substantial intrinsic cellular diversity, with cells specializing both temporally and spatially.
• This cellular specialization is key to the intestine's ability to regulate diverse functions.
• The findings provide a foundation for future research into cell-specific intestinal responses to environmental factors and diet.