Ribosomal shunt

Ribosomal shunting is a translation initiation depending on cap-dependent discontinuous scanning, where ribosomes are loaded onto mRNA at the 5'-cap structure, start scanning for a short distance before bypassing the large internal leader region and initiating at a downstream start site.

Shunting operates in plants, animals, and yeast translational systems, both in vivo and in vitro.

Vertebrate protein BIRC3 has been show to be exclusively translated by a stress-modulated ribosome shunt.(PubMed). Interestingly, this protein may be involved in cell innate immunity against virus infection (PubMed).