New non-coding RNA discovered
6 Aug 2014 by Evoluted New Media
A new species of non-coding RNA has been discovered by researchers in Germany, who believe these sections of the genome may play a role at the epigenetic level. Around 2% of the human genome codes for proteins, the rest – referred to junk DNA – does not, but it is unclear what role they do play. “This is one of the big questions currently hanging over genome research,” said Dr Jörg Hackermüller, a bioinformatician at the Helmholtz Centre for Environmental Research (UFZ). “They continue to represent vast blank spots on the genomic map – there is still a lot waiting to be discovered here,” Together with colleagues at the Fraunhofer Institute for Cell Therapy (IZI) and Leipzig University, Hackermüller has demonstrated that the production of non-coding RNA is precisely regulated, and they suspect that they might regulate cellular processes or have a role in the modified immune system following exposure to environmental toxins. The team also discovered a species of non-coding RNA called macroRNA, which is approximately 50 to 200 times the size of regular, protein-coding RNA. “What is remarkable is that parts of these macroRNAs are conserved throughout mammals as well as bird and reptiles,” said Professor Friedemann Horn from Leipzig University. “Furthermore, in aggressive types of brain tumours, several macroRNAs are produced much more actively than in tumours with a good prognosis. This is further evidence that non-coding macroRNAs play an important role in cellular processes.” The research in Genome Biology show that the transcription of non-coding regions in the genome is precisely regulated by cellular signalling pathways – and on a huge scale; up to 80% of RNA copies were non-coding. “We did not expect such a magnitude,” said Hackermüller. “This is not indicative of a chance product – it is highly likely that the non-coding RNAs perform a similarly important function to that of protein-coding RNA.” Hackermüller suspects that non-coding RNAs have an important function at the epigenetic level, for example as a type of cellular long-term memory. “This could often explain why the health effects caused by exposure to hazardous environmental substances often do not emerge until years later,” he said. Further research will test the influence of environmental pollutants on the appearance of non-coding RNAs in immune cells. Cell cycle, oncogenetic and tumor suppressor pathways regulate numerous long and macro non-protein coding RNAs