Fig. 6. Effect of BSA-NES on the inefficient export of a U1-ESE RNA. ³²P-labeled U1-(GAA)₁₂ RNA was microinjected into Xenopus oocyte nuclei together with ³²P-labeled U1DSm, and U6Dss RNAs, with either 4 mg/ml BSA-NES (lanes 5 and 6) or BSA-mut (lanes 7 and 8) or without proteins (lanes 1-4). RNA was analyzed as in Fig. 1B. N, nuclear fractions; C, cytoplasmic fractions.