Washington: Scientists have provided a deeper insight into the mystery of origins of life and how life on Earth began 3.6 billion years ago.
University of North Carolina researchers provided evidence on how the genetic code developed in 2 stages and how primordial chemicals were able to evolve into the first cells on Earth.
Recent research has revealed how the primordial soup created the amino acid building blocks, and there was widespread scientific consensus on the evolution from the first cell into plants and animals. But it's still a mystery how the building blocks were first assembled into the proteins that formed the machinery of all cells.
Now, two long-time University of North Carolina scientists - Richard Wolfenden, PhD, and Charles Carter, PhD - have shed new light on the transition from building blocks into life some 4 billion years ago.
The findings fly in the face of the problematic "RNA world" theory, which posits that RNA - the molecule that today plays roles in coding, regulating, and expressing genes, elevated itself from the primordial soup of amino acids and cosmic chemicals to give rise first to short proteins called peptides and then to single-celled organisms.
Wolfenden and Carter argued that RNA did not work alone; in fact, it was no more likely that RNA catalyzed peptide formation than it was for peptides to catalyze RNA formation.
This was believed to be a single-cell organism with a few hundred genes, which had complete blueprints for DNA, RNA and proteins.
But before 3.6 billion years ago, there is little evidence about how LUCA arose from the boiling cauldron of chemicals that formed on Earth after its creation 4.6 billion years ago.
It has long been thought RNA, which plays a key role in genetics and biological coding, arose by itself.
This gave rise to short proteins called peptides and ultimately single-celled organisms - but how this happened, known as 'RNA world theory', has perplexed scientists.
Now, Dr Wolfenden and Dr Carter argue that RNA did not work alone. In fact, they say there was this second, earlier process of protein folding that helped RNA to arise.
The scientists note that there are still plenty of unanswered questions about the origins of single-celled organisms on Earth.
But this latest research could provide a useful clue in piecing together just what happened in this 'blink of an eye', relatively speaking, 3.6 billion years ago.
The study is published in the Proceedings of the National Academy of Sciences.
