Brain cytosolic (Cs), cytoskeletal (Ct), and nuclear (Nu) fractions of human
(left panel) and mouse (right panel) were denatured prior to separation by 2-D
electrophoresis, and DYRK1A was detected in Western blots with mAb 8D9. In
cytosolic fraction, DYRK1A was observed exclusively at pI 8.7, and after
dephosphorylation with λPPase (λ), its pI shifted to 9.0. In the
cytoskeletal and nuclear fractions of both human and mouse brains, different
patterns were observed: several discrete focused spots of DYRK1A with pI
7.2–8.2 in the cytoskeletal fraction, and several overlapping spots with
pI 5.0–6.5 in the nuclear fraction.