A new study conducted by researchers from Technion – Israel Institute of Technology along with their colleagues from Uruguay, Switzerland, Sweden, France, Britain and Argentina suggests that mechanisms responsible for sexual reproduction may have emerged about a billion years before sexual reproduction itself became a thing, according to Haaretz.
In their study published in Nature Communications last month, the researchers note how fusion proteins similar to those found in eukaryotes and some viruses, and akin to those that fuse sperm and egg cells together, appear similar in structure to a fusion protein called Fusexin1 found in some single-celled organisms known as archaea.
Furthermore, the team managed to confirm via an experiment with hamster cells that the archaean fusion proteins can be used to fuse eukaryotic cells, just like the fusion proteins found in eukaryotes.
While it isn’t exactly clear what use fusion proteins would have to single-cellular organisms millions of years before sexual reproduction on planet Earth started, the newspaper points out how archaea could exchange genes with other archaea or even bacteria via membrane fusion.