Post-Transcriptional RNA Processing
DNA transcription occurs in a cell's nucleus. The RNA that is synthesized in this process is then transferred to the cell's cytoplasm where it is translated into a protein. In prokaryotes, the RNA that is synthesized during DNA transcription is ready for translation into a protein. Eukaryotic RNA from DNA transcription, however, is not immediately ready for translation. Post-transcriptional modifications OF RNA accomplish two things: 1) Modifications help the RNA molecule to be recognized by molecules that mediate RNA translation into proteins; 2) During post-transcriptional processing, portions of the RNA chain that are not supposed to be translated into proteins are cut out of the sequence. In this way, post-transcriptional processing helps increase the efficiency of protein synthesis by allowing only specific protein- coding RNA to go on to be translated. Without post-transcriptional processing, protein synthesis could be significantly slowed, since it would take longer for translation machinery to recognize RNA molecules and significantly more RNA would have to be unnecessarily translated to achieve the same results.