"What this discovery tells us is a complete fundamental reworking of the relationship between a gene, messenger RNA and a protein. It's more complicated than we realize," Schoenberg said.
The research is published online in the open-access journal Cell Reports.
That fragments of mRNA could exist at all in the cell's main body was first reported by other scientists in 1992. Years later, Schoenberg asked a postdoctoral researcher in his lab to revisit these unexpected RNA fragments and confirm they exist. The postdoc's experiments showed that these mRNA, thought to be the dregs left over from their degradation, had caps on them - suggesting they still had the potential to function in protein production. Schoenberg, also director of Ohio State's Center for RNA Biology, has been investigating this cytoplasmic capping operation ever since.
In 2009, he and colleagues reported the discovery of two enzymes in the cell's main body that would enable mRNA capping to occur completely outside the nucleus and in the cytoplasm instead.
In the current studies, Schoenberg sought to determine the physiological significance of this capping operation. The researchers engineered a way to block cytoplasmic capping in cells in the lab and then looked at changes in more than 55,000 RNAs.
This interference with cytoplasmic capping revealed that two different types of pathways could exist in the cells - some mRNAs remained stable without their caps, while others without caps were rapidly destroyed. This finding indicated that mRNAs can los
|Contact: Daniel Schoenberg|
Ohio State University