Specificity:Reacts with the ~50 kD Parkin protein. Western blots of rat brain may also show a band of unknown origin at ~44 kD. Binds to the second RING domain (C-terminal region) of parkin protein. While the specific 50kD parkin signal was detected in Western blots of high salt fractions of wild-type mouse brain, no signal was detected in parkinnull mouse brain samples. Reactivity has been confirmed with recombinant human Parkin protein, human Parkin-transfected CHO cells, and human, mouse, and rat brain tissue homogenates. Species Sequence Homology: the human Parkin sequence shares ~83% sequence homology with mouse and rat.