Post-transcriptional control of gene expression
Post-transcriptional modification is the physical alteration of the newly formed mRNA strand before it starts producing proteins. This process occurs after transcription (DNA to RNA).
Newly transcribed mRNA is often called the primary transcript or pre-mRNA.
Post-transcriptional modification gives an opportunity to alter gene expression. This modification can have significant effects on the amount mRNA that is translated.
Post-transcriptional modification is most common in eukaryotes.
Eukaryotic transcription occurs in the nucleus while translation occurs in the cytoplasm.
This means that there are several opportunities for the mRNA to undergo modification, as transcription and translation are spatially separated.After modification, mRNA leaves the nucleus through the nuclear pores.