Mouse Hemokinin-1 Decapeptide Subjected to a Brain-specific Post-translational Modification.

BACKGROUND/AIM: The tachykinin mouse hemokinin-1, expressed by the mouse Tac4 gene, produces either analgesia or nociception, interacting with the neurokinin 1 receptor. TAC4 precursor processing is not identical to the processing of the TAC1 precursor, for the release of substance P (amidated undecapeptide). The characterization of the mouse hemokinin-1 sequence was required.

MATERIALS AND METHODS: We developed anti-tachykinin-specific antibodies for the immunoaffinity purification of tachykinins.

RESULTS: Using MALDI-ToF, we identified mouse hemokinin-1 as an amidated decapeptide expressed in murine brain and periphery. Furthermore, we interestingly observed an additional mass peak corresponding to acetylated mouse hemokinin-1 and this post-translational modification is brain-specific, not detected in the periphery.

CONCLUSION: We suggest that the N-terminal acetylation of the peptide provides greater potency for ligand-receptor interactions during neural cell signaling.