Biologists from the University of Pennsylvania found out what long non-coding RNA (lncРНК), whose role in the genome for a long time remained unknown. It turned out that, even if the RNA itself does not perform any function, its encoding gene may be a regulator of the activity of another gene. A study published in the journal Molecular Cell. Press release available on the website of the University of Pennsylvania.
lncРНК, the length of which reaches at least 200 nucleotides, are abundant in cells, but these molecules do not contain information on protein sequence and are not involved in gene regulation. The last they differ from the small non-coding RNA.
In previous work, the researchers were able to identify over a thousand different lncРНК cells in mice and humans. Biologists have discovered that genes encoding them are located in the region of DNA containing enhancers — short stretches that bind to molecules called transcription factor, and amplify, thus, the activity of adjacent genes.
In the new study, the researchers studied the function of the enhancer, which is located at the beginning Lockd gene encoding one of the many non-coding RNA. lncРНК of this gene are found in red blood cells of mice in some other cell types. One possibility was that they perform an unknown function in cells other that the gene Lockd itself plays a role, and its RNA is merely a byproduct.
The promoter of the gene Lockd is the starting point for the synthesis process lncРНК — contains sites that bind transcription factors. They lie close to neighbouring cdkn1b gene, which encodes a protein important for the regulation of cell division. It turned out that when you remove Lockd, cdkn1b activity is reduced by 70 percent. At the same time the suppression of the synthesis of lncРНК in pristine Lockd does not affect cdkn1b.
Scientists have found that the promoter of the gene Lockd due to the torsion of the DNA molecule comes in contact with the cdkn1b gene promoter and thus acts as an enhancer that increases the activity of the latter.
The researchers emphasize that their discovery does not mean that she lncРНК plays no role, however, it was shown that genes and their corresponding RNA can perform various functions.Related posts: