The birth of a cell has still remained as a mystery with researches coming up with new discoveries over and over. A recent study conducted by researchers at the Case Western Reserve University, have come to identify a cellular mechanism which is considered essential for normal cell function maintenance.
The study, led by Dr. Eckhard Jankowsky, has examined the role of a protein complex called TRAMP in the formation of RNA or ribonucleic acid in the cell. They have been able to find out a specific function of the protein called Mtr4p.
According to them, the protein has a part to play in a process which kicks off the degradation of slecet RNAs. Dr. Jankowsky explained that improperly assembled, defective or obsolete RNA can easily come in the way of ongoing processes. To overcome this problem, several efficient RNA degradation pathways are in place and TRAMP is responsible for the initiation of one of these pathways.
The protein complex works by recognizing the RNAs that are about to degrade and by tagging them with a stretch of adenosines, one of the four nucleotides which builds RNA. The number of adenosines in the tag has to have a limit because RNAs with excessive adenosines will no longer be regarded as degradation targets.
Researchers studied the molecular mechanism by which the RNAs are marked by the TRAMP complex. The TRAMP includes enzyme poly(A) polymerase Trf4p, the Zn-knuckle protein Air2p and Mtr4p, an RNA helicase. Helicases are known for unwinding helices, but in the protein complex, the helicase Mtr4p has been found to control the number of adenosines added.
The researchers have described how the process by which the helicase regulates the number of adenosines that have been attached. The helicase counts the number of adenosines attached by the polymerase and then does some adjustment on the polymerase activity.
"Our work explains an important step in the mechanism by which cells mark RNAs for degradation in the nucleus," Dr. Jankowsky said. "Appropriate tagging is critical for cell function."
