(1) Splicing-the introns are removed and exons are joined together.
(2) capping -methyl guanosine triphosphate is added to the 5-end of hnRNA.
(3) Tailing- adenylate residues (200-300) are added at 3-end in a template
After these three process, fully processed mRNA is released from nucleus into cytoplasm for protein synthesis.