A research team has recently made a significant discovery about the evolutionary age of different type of cells in a small animal called Caenorhabditis elegans (C. elegans). By using single-cell transcriptomic data and refined phylostratigraphy, the team determines the transcriptomic age of individual cells, which means they are able to estimate the evolutionary origin of different cells based on the age of the genes expressed in the cells.

 

Their findings shed light on the cellular basis of the 'hourglass' pattern of animal development, revealing significant variation in the transcriptome age of different cell types. “Using C. elegans as an example, we showcase how the transcriptome age at the single-cell level can provide insight into the cellular basis of developmental innovation and help understand the functional diversity and evolutionary origin of cell types,” said Dr Fuqiang MA, a Postdoctoral Fellow of HKU School of Biological Sciences and the first author of the paper.