Loss of an individual proteasome subunit alters motor function but not cognitive function or ambulation in mice.

The proteasome is a large intracellular protease, composed of multiple subunits, that is present in all cells. In the present study we examined motor function, cognitive function, and ambulation in transgenic mice that lack the low molecular protein 2 (LMP2) proteasome subunit. Comparison of LMP2 knock out (LMP2 KO) mice and non-transgenic mice of the same background demonstrate that LMP2 KO mice exhibit a higher degree of motor function, but possess a similar level of cognitive function and ambulation, as compared to non-transgenic control mice. Interestingly, LMP2 KO mice also exhibited increased body weight as compared to non-transgenic mice. These data demonstrate for the first time that specific proteasome subunits may play a role in regulating both brain function and body weight.