Post transcriptional Regulation Control of RNA Processing. Splicing Mechanism including splice site consensus sequences, snRNA s, spliceosome apparatus and lariat formation. In several genes of C. elegans. First found in mitochondria of trypanosomes where U s were seen to be inserted or deleted in the mRNA following transcription. The replacement causes the formation of a UUA stop codon and a truncated protein in the intestine.
Larger molecules are active transported via sequence specific mechanism.
RNA s need to be associated with proteins to be transported. This may control unprocessed RNAs from leaving nucleus. Histone mRNA in sea urchins eggs are completely processed but inhibited from exiting the nucleus. Histone mRNA regulated during cell cycle. Activation of nuclease is cell cycle dependent.