where does pre mrna splicing occur in eukaryotes
RNA splicing In molecular biology, splicing is the editing of the nascent precursor messenger RNA (pre-mRNA) transcript into a mature messenger RNA (mRNA). After splicing, introns are removed and exons are joined together (ligated). For nuclear-encoded genes, splicing takes place within the nucleus either during or immediately after transcription. For those eukaryotic genes that contain introns, splicing is usually required in order to create an mRNA molecule that can be translated into protein. For many eukaryotic introns, splicing is carried out in a series of reactions which are catalyzed by the spliceosome, a complex of snRNPs. Self-splicing introns, or ribozymes capable of catalyzing their own excision from their parent RNA molecule, also exist.