Set up the reaction mixture in a 1.7 mL Eppendorf tube with 1.4mL purified LRRK2 protein, 1x kinase buffer with 1millimolar (mM) ATP and 0.01U/µL GST-Prescission Protease (to remove the Flag tag).

Incubate samples at 4°C.

Add Glutathione beads to remove GST-Prescission Protease.

Concentrate samples by centrifugal filters and dialyze at 4°C against dialysis buffer.

Check autophosphorylation by Western blotting using a LRRK2 phospho-specific (pT1357) antibody.

Determine protein concentration by SDS-PAGE using Bovine Serum Albumin (BSA) as standard and used without freezing in the liposome tubulation experiments.