Plant research reveals new role for gene silencing protein

A DICER protein, known to produce tiny RNAs in cells, also helps complete an important step in gene expression. Gene expression, when an organism's DNA is transcribed into a useable product, requires activation via a promoter or an external trigger. Plant research 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.