Plant Research Reveals New Role for Gene Silencing Protein
News Mar 30, 2012
The expression of a gene, when an organism's DNA is transcribed into a useable product, requires activation via a promoter or an external trigger. Plant research to be published in Science helps to show that later stages of transcription are just as important. This is likely to apply to other organisms, including humans.
Termination is the final stage of transcription. Successful termination is dependent on DNA being transcribed into RNA with the correct sections, including a certain length tail.
Scientists at the John Innes Centre on Norwich Research Park have found that where effective termination through the normal mechanisms has not occurred, DICER-LIKE 4 (DCL4) steps in to tidy up. Without termination, transcription continues down the chromosome unchecked.
In this way, DCL4 plays a crucial and previously unknown role in transcription termination. It helps formation of the gene product. DCL4 is more commonly known to play a part in the opposite effect, gene silencing.
"DCL4 is a back-up to termination processes, helping a gene to be successfully expressed," said lead author Professor Caroline Dean from JIC, which is strategically funded by BBSRC.
The findings may help explain why gene silencing happens so often with transgenes. It was not known that so much attention should be given to the tail end of a gene.
"Our research shows that for successful expression the end of a gene is just as important as its beginning," said Dean.
When termination fails a lot of aberrant RNA is made -- this is degraded as part of a cell's quality control mechanism. This can have consequences for other sequences in the genome that match the aberrant RNA.
"If a gene ends badly, aberrant RNA will trigger silencing pathways," said Dean.
DCL4's ability to step in to rescue poor termination makes it important for both successful gene expression, a previously unknown role for it, and gene silencing.
Extra-Resistant Wheat is Created From New Gene CombinationNews
A new combination of different strains of resistant wheat may help farmers avoid a common fungal disease.READ MORE
Algorithm Unearths Over 1000 Antibiotic Proteins in a Few HoursNews
The algorithm identified 10 times more peptide variations than all previous discoveries combined, aiding the hunt for new antibiotics.READ MORE
Protein That Helps Keep Breast Cancer Dormant IdentifiedNews
A protein kinase that stops breast cancer cells growing and spreading has been outlined in new research.READ MORE