Protein N-terminal asparagine amidohydrolase (Ntan1)

N-terminal asparagine deamidase that mediates deamidation of N-terminal asparagine residues to aspartate. Required for the ubiquitin-dependent turnover of intracellular proteins that begin with Met-Asn.

These proteins are acetylated on the retained initiator methionine and may then be altered by the removal of N-acetyl methionine by acylaminoacid hydrolase (AAH). Conversion of the consequent N-terminal asparagine to aspartate by PNAD leaves the protein susceptible to arginylation, polyubiquitination and degradation according to the N-end rule.