Peptide sequence: RGTPKGKTGR GGRQKNRFGL PGPSQTNLPN SQASQDVASQ PFSQGALTQG Sequence homology: Cow: 100%; Dog: 100%; Guinea Pig: 79%; Horse: 93%; Human: 100%; Mouse: 93%; Rat: 93%; Zebrafish: 83%. Upf1 was identified as an active component in nonsense-media