FIG. 2.

Unlike most other general transcription factors and Pol II, P-TEFb is recruited to mitotic chromosomes before nuclear envelope/lamina reassembly. (A) Coimmunofluorescence followed by confocal microscopic analyses of the localizations of CycT1 (red) and lamin B1 (green) in HeLa cells at various stages of mitosis (left) was performed. Staining of chromosomal DNA by DAPI (blue) and a merge of all three stainings in the same cells are also shown. Bar, 5 μm. (B) The localizations of lamin B1, TFIIB, TFIIF (Rap30), Pol II (the cells under discussion are indicated by an arrow), and Cdk9 in HeLa cells at mid- to late anaphase were examined by coimmunofluorescence as in panel A.