The present invention provides means and methods for equipping a polypeptide of interest at its C-terminus with a versatile adaptor amino acid that allows the functionalization of the polypeptide of interest.

Described herein is a method for improving or stabilizing cardiac function by inhibiting tubulin carboxypeptidase (TCP). Also described herein is a method for treating heart failure in humans comprising dosing a patient with a therapeutic which interferes with detyrosinated microtubules in cardiomyocytes. Also provided are viral vectors which comprise a nucleic acid encoding a tubulin tyrosine ligase (TTL) gene under the control of regulatory elements direct expression thereof. Compositions are also provided which contain such viral vectors formulated for delivery to a human patient.