‘Non-coding’ pieces of RNA can encode short proteins that regulate genes, researchers have found.
Various non-coding RNA molecules do not produce protein but either regulate gene expression or carry out other functions in the cell. Many researchers question whether the rest of the apparently non-coding RNA made in cells has any function.
Some believe many RNA molecules in the cell are merely junk — the accidental by-products of the process that transcribes RNA from a DNA template.
“We missed microRNA for decades — maybe we missed ‘micropeptides’ for even longer.”
Researchers in Japan have found a ‘non-coding’ RNA that directly codes for four peptides, short chains of amino acids from 11 to 32 amino acids long, that act to regulate fruitfly development. It is likely that many more of these mysterious RNA molecules could produce peptides too small to be considered true proteins but which have important functions within cells.
This potentially paradigm-changing discovery “might be something very big,” says Claude Desplan, a developmental biologist at New York University. “We missed microRNA for decades — maybe we missed ‘micropeptides’ for even longer.”
“Short peptides could be lurking virtually anywhere in the genome” says Desplan.
These findings could also have implications for how we view so called psueodgenes, which have long been thought to be defunct relics of protein-coding genes. “Maybe this would provide a new way for pseudogenes to have some sort of function,” he says.