Fig. 8. Effects of overexpression of HDACm and HDACm-2m on the endogenous chromatin of Xenopus oocytes. Vector expressing HDACm (+) or HDACm-2m (S421A, S423A) was injected into GVs of stage IV oocytes and after 24 hours nuclear spreads were made to view lampbrush chromosomes. Some oocytes were co-injected with 50 ng of bromo-UTP to detect endogenous RNA transcription. Chromosomes were immunostained using antibodies against HDACm (A,F), incorporated bromouridine (BrU) (C,H) and histone H4 acetylated at residue lysine12 (H4AcK12) (D,I). All preparations were counterstained with 4,6-diamidino-2-phenylindole (DAPI) to detect chromosomal DNA (B,E,G,J). Bars, 20 µm.