<p> The residues upstream of this domain are the probable palmitoylation sites, particularly two cysteines. The domain has a putative PEST site at the very start that seems to be responsible for poly-ubiquitination [<cite idref="PUB00044343"/>]. PEST domains are polypeptide sequences enriched in proline (P), glutamic acid (E), serine (S) and threonine (T) that target proteins for rapid destruction. The whole domain, in conjunction with a C-terminal domain of the longer protein, is necessary for dimerisation of the whole protein [<cite idref="PUB00044344"/>]. </p> Membrane-associated guanylate kinase (MAGUK), PEST domain, N-terminal