Estimation of C. elegans cell- and tissue volumes

Abstract

Although C. elegans is one of the best-studied model organisms, an estimate of its cell sizes and tissues is missing. Here we used the Virtual Worm that is based on electron microscopy images to calculate a zeroth-order approximation of cell and tissue sizes of C. elegans. We conclude that the intestine is the largest tissue, followed by the hypodermis, gonads, body wall muscles, pharynx, and neurons. Thus, we provide an approximation of tissue volumes of young adult C. elegans.

Figure 1. Quantification of C. elegans’ cell and tissue volumes

a) Workflow of our approach. b) On the left: tissue volumes determined with the two Blender plugins “3D print” or “Mesh Calculator”. For the gonad and reproductive system, the volume comprising the rachis and germ cells filling it in a lighter shade to distinguish them from somatic tissue. On the right: visualization of the analyzed tissues. c) Top: relative contribution of tissues to the final volume. The extracellular cuticle was excluded from this analysis. Bottom: same analysis but including rachis and non-somatic germ cells. d) Top: relative contribution of tissues to the number of nuclei, the number of diploid genomes. Bottom: same analysis but including the non-somatic germ cells. e) Cell volume, grouped by different tissues, displayed in a linear y-axis. Rachis and non-somatic germ cells were excluded from the analysis. f) Cell volume normalized per diploid genome, grouped by different tissues, displayed in a log₁₀ y-axis. Rachis and non-somatic germ cells were excluded from the analysis. g) Distribution of cell volumes (log₁₀ y-axis). h) Distribution of cell volumes per diploid genomes (log₁₀ y-axis). For details, raw data, and calculations, please see Extended Data.