Figure 4.

Subcellular localization of XIST RNA. XIST RNA is known to localize to the nucleus in female somatic cells, and it apparently is associated with the inactive X chromosome. To determine whether XIST localization was normal in the inactive X hybrid (X8–6T2S1) and the XIST reactivant hybrid (Xa5aC-4F5), we isolated RNA from cytosolic and nuclear extracts and analyzed these fractions by semiquantitative RT-PCR. PCR products were derived from either 0.5 or 1.0 μg of RNA in the RT reaction (see Materials and Methods).