Optimized protocol to detect protein UFMylation in cells and in vitro via immunoblotting

Ubiquitin-fold modifier 1 (UFM1) system is a recently identified ubiquitin-like modification with essential biological functions. Similar to ubiquitination, the covalent conjugation of UFM1 (UFMylation) to target proteins involves a three-step enzymatic cascade catalyzed sequentially by UFM1-activating enzyme 5 (UBA5, E1), UFM1-conjugating enzyme 1 (UFC1, E2), and UFM1-specific ligase 1 (UFL1, E3). Here, we provide an optimized protocol adapted to previously reported methods for detecting the UFMylation of target protein in human cells and in vitroassays,respectively, with high reliability and reproducibility.