Western analysis of SmN. (a) SmN in human lymphoblasts. N, normal; AS, AS139; PWS, PWS109. (b) SmN in mouse tissues. ES, embryonic stem cells; PW, murine PWS model brain extract; WT, normal mouse brain extract. SmA, SmN, SmB′, SmB, SmC, and SmD complex are indicated in the left margins of a and b.