Without a certain ancestral gene, life on Earth would be slime. Scientists have identified a common ancestral gene that enabled the evolution of advanced life more than a billion years ago.
"If the duplications and subsequent mutations of this gene during evolution didn't happen, then life would be completely different today," Steven Pelech, one of the researchers, said in a news release. "The most advanced life on our planet would probably be bacterial slime."
Plants, animals, mushrooms and other organisms on Earth exist because they are made up of eukaryotic cells that are larger and far more complex than bacteria. Inside of these eukaryotic cells are hundreds of organelles that perform diverse functions to keep them living.
The ability to transmit signals from one part of the cell to another allowed cells to come together to form living systems, paving the way for the evolution of intelligent life. Research into the enzymes that allow this has become important to medicine. More than 400 human diseases like cancer and diabetes are linked to problems with cell signaling. Today, about one-third of all pharmaceutical drug development is targeted at protein kinases, which are highly interactive signaling proteins that play a similar role to the neurons in the brain by transferring information throughout the cell by a process known as protein phosphorylation.
"From sequencing the genomes of humans, we knew that about 500 genes for different protein kinases all had similar blueprints," said Pelech. "Our new research revealed that the gene probably originated from bacteria for facilitating the synthesis of proteins and then mutated to acquire completely new functions."
The same gene that gave rise to protein kinases also led to the formation of a group of enzymes known as choline and ethanolamine kinases. The choline kinase enzyme is critical for the production of phosphatidylcholine, which is a major component of the membranes that wrap around eukaryotic cells and their organelles.
In fact, the gene is found in all complex organisms, including plants and animals. This gene could have led to the evolution of more complex life on Earth. In other words, scientists have pinpointed the gene that allowed organisms to diversify in the early years of our planet.
