Findings could have implications for medicine for more than 400 diseases

What do you have in common with a dung beetle, a monkey tree and a blue whale?

The answer is an ancestral gene that could have been the key to life as we know it.

Researchers have identified an ancestral gene common to all life on the planet that enabled the evolution of advanced living organisms.

Without it, they said the most advanced life on the globe could still be green slime.

Researchers have identified an ancestral gene common to all life on the planet that enabled the evolution of advanced living organisms. Without it, they said the most advanced life, and its resulting DNA (helix illustrated), would still be green slime

'If the duplications and subsequent mutations of this gene during evolution didn't happen, then life would be completely different today,' said Steven Pelech, a professor in Division of Neurology in the UBC Faculty of Medicine.

'The most advanced life on our planet would probably still be bacterial slime.'

Researchers at the University of British Columbia identified the gene that gave rise to protein kinases - a large group of enzymes that helped cells to grow and send information from one part to another.

These highly interactive proteins play a role similar to the neurons in the brain by transferring information throughout the cell.

The development of these enzymes enabled plants and animals to evolve and become more complex than bacteria. The same gene that gave rise to protein kinases also led to groups of enzymes know as choline and ethanolamine kinases also responsible for helping life evolve. The protein kinases are pictured

DISCOVERY OF THE 'LIFE' GENE Researchers at the University of British Columbia identified the gene that gave rise to protein kinases - a large group of enzymes that enabled cells to be larger and to rapidly transfer information from one part to another. We share this gene with all other plants and animals on the planet. This finding helps give an insight as to how we evolved from bacteria. Research into these enzymes has also become very important to medicine. More than 400 human diseases like cancer and diabetes are linked to problems with cell signaling. Disease occurs when a cell gets misinformed or confused. Today about one-third of all pharmaceutical drug development is targeted at protein kinases. Advertisement

The development of these enzymes enabled plants and animals to evolve and become more complex than bacteria.

Plants, animals, mushrooms and more all exist because they are made up of cells called eukaryotic cells that are larger and more complex than bacteria.

The same gene that gave rise to protein kinases also led to the formation of a group of enzymes know as choline and ethanolamine kinases.

The choline kinase enzyme is critical for the production of a major component of the membranes that wrap around eukaryotic cells, but is missing from bacteria.

It was already known that most protein kinases came from a common ancestor.

'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.'

Pelech said that the approach they used to study the evolution of this gene could be adapted to study other important protein families and could eventually lead to the creation of a version of the evolutionary tree of life.

The researchers said that the approach they used to study the evolution of this gene could be adapted to study other important protein families and could eventually lead to the creation of a version of the evolutionary tree of all life on Earth

The bacteria in which the gene originated might also have lived in a cooler environment than previously thought, according to a separate study.

WAS LIFE FORGED IN ICY SEAS? New research shows that temperatures were cooler than we had thought on our planet around 3.5 billion years ago. Previous research suggested that the ocean in which rocks from South Africa formed, about 3.5 billion years ago was around 85°C. But Maarten de Wit at the Nelson Mandela Metropolitan University in Port Elizabeth, South Africa, now says the ocean temperature was much colder and even icy. They looked at rocks formed out of ocean sediments that had not been exposed to hydrothermal activity and found evidence that a mineral called gypsum was able to grow, which only would have formed in deep and cold seas they said. Advertisement

New research shows that temperatures were cooler than we had thought on our planet around 3.5 billion years ago.

Previous research suggested the ocean in which rocks from South Africa formed, about 3.5 billion years ago was around 85°C.

But Maarten de Wit at the Nelson Mandela Metropolitan University in Port Elizabeth, South Africa, now says the ocean temperature was much colder and even icy.

Evidence for this chill was found in South Africa's Barberton Greenstone Belt, which contains some of the oldest and best preserved rocks on Earth.

Along with Harald Furnes, a geologist at the University of Bergen in Norway, de Wit spent six years mapping and sampling the Barberton.

They looked at rocks formed out of ocean sediments that had not been exposed to hydrothermal activity and found evidence that a mineral called gypsum was able to grow, which only would have formed in deep and cold seas they said.

'This is the first evidence that over the entire [last] 3.5 billion years, Earth has operated within a temperature range that suits life,' said de Wit.

According to a separate study, this gene may have also have lived in a cooler environment than previously thought. By studying a mineral called gypsum (pictured), which only would have formed in deep and cold seas, researchers believe Earth was a 'snowball' at the time that life is thought to have emerged

Ambient ocean temperatures must have been close to 0° Celsius. 'Because there was ice near sea level at low latitudes, the oceans and atmosphere were globally likely to be cold,' said de Wit.

The scientific community are not in agreement over this finding.

Paul Knauth at Arizona State University in Tempe, who has argued in favour of warm ancient oceans, told New Scientist that experiments show gypsum can actually grow well in water that is at 80°C.