Genomic evidence suggests that some protein coding genes found across all living organisms existed before the last universal common ancestor (LUCA) of life on Earth.
LUCA is the most ancient organism that can currently be studied using evolutionary methods and is thought to have lived around 4.2 billion years ago.
A collaborative team of evolutionary biologists focused on rare gene families called universal paralogs – genes that appear in at least two copies in the genomes of nearly all life forms.
In the recent analysis, all known universal paralogs were found to be involved in basic cellular functions such as protein production and transport of molecules across cell membranes, indicating that these core processes were already established prior to LUCA's appearance.
The findings were published in Cell Genomics.
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