Now, before our messenger RNA actually leaves the nucleus and enters the cytoplasm where it attaches to the ribosomes and undergoes protein synthesis, our messenger RNA has to undergo several important types of modifications several important types of post transcriptional processes. Now, within the nucleus of our cell we produce a molecule known as the precursor mRNA. So the mRNA that is formed directly following the process of transcription before any type of post transcriptional modification actually took place is known as the precursor mRNA or simply as the mRNA or the pre mRNA. So this is the mRNA that has not yet undergone the necessary modification processes that are needed for the molecule to exit the nucleus and enter the cytoplasm. And there are three important types of post transcriptional modifications. So we have the addition of the five guanosine triphosphate cap, we have the polyadenylation of the three N tail and we have the splicing of our axons and the removal of our introns.