靶标信息
It is uncertain whether Met-1 or Met-76 is the initiator. Transcript evidence available at present time points at Met-76. In this short version of the protein, the signal peptide cannot be predicted and the irisin peptide is severely truncated. The first initiation codon corresponds to a non-AUG site, an N-terminal ATA codon. This initiation codon has been annotated as it is in good Kozak context and it is conserved in other primates, including gibbon, chimpanzee and gorilla. Although the existence of such a form has not been demonstrated in human, western blot analysis following endurance exercise shows the presence of an irisin peptide of similar size in human and mouse plasma , suggesting the existence of full-length irisin in human, at least in some tissues. However, expression from Met-1 may be less efficient than that from Met-76.