Fig. 7. Import of recombinant Xp54 into the oocyte nucleus and binding to nascent RNP is dependent on the transcriptional state of the chromatin. (A) The nucleocytoplasmic distribution of T7-p54, T7-V and T7-CT expressed in stage VI oocytes compared with binding of the recombinant proteins to the RNP matrix of lampbrush chromosomes is shown. The chromosome spreads were immunostained with anti-T7 IgG and FITC-conjugated anti-mouse IgG, post-stained with DAPI. Phase contrast (PC) microscopy images are also shown. (B) As described in (A) but with treatment of the oocytes with 2 ng/ml trichostatin A (TSA) or 0.5 µg/ml -amanitin (-AM) for two hours before addition of LMB. (C) Sedimentation of T7-p54 in complexes isolated from 50 stage VI oocytes and from nuclei and cytoplasms of 50 stage VI oocytes treated with TSA.