In RNA editing spliceosomes change the base sequence of the primary transcript and therefore the protein for which it codes. a combination of spliceosomes and enzymes creates different primary RNA transcripts from the same DNA sequence. different spliceosomes in different cells create different RNA sequences from the same primary transcript. enzymes change the base sequence of the primary transcript and therefore the protein for which it codes. microRNAs in different cells create different primary RNA transcripts from the same DNA sequence.