TbLpn is methylated in vivo . TbLpn was immunopurified from PF T. brucei cytosolic extracts using anti-TbLpn polyclonal antibodies as described under Material and Methods. As a negative control, the cytosolic extract was incubated in the absence of antibodies. Proteins present in the starting cytosolic fraction (C), as well as the bound (B) and unbound fractions (U) were separated on a 10% polyacrylamide gel and transferred to PVDF. The presence of TbLpn in the immune complexes was assessed by probing the membrane with anti-TbLpn polyclonal antibodies (1:1,000), followed by goat anti-rabbit IgGs. To determine whether TbLpn contains methylated arginines, the blot was probed with anti-mRG polyclonal antibodies (1:1,000) , followed by goat anti-rabbit IgGs. Signals were detected using chemiluminescence.