Splicing takes place on spliceosomes containing snurps composed of snRNAs and spliceosome proteins. Spliceosome proteins were recognized long ago because lupus patients make antibodies that react against them. The intron RNA is released as a lariat. Alternate splicing, skipping exons, particularly near the beginning and end of genes, is common for genes expressed in more than one tissue. This is thought to protect the message.
Eukaryotic messages contain a tail of poly A. a.
A string of A's is put on by a polymerase that doesn't need a template. Polyadenylation probably stabilizes the mRNA and makes it more transportable from nucleus to cytoplasm. H. Translation 1. Translation is the process of making the primary sequence of proteins from the amino acids. The translation apparatus consists of tRNAs and ribosomes.