Fig. 4. H3SP staining of germinating spores reveals a deficiency of H3SP reactivity in ark1.
cells. (A) Spores arising from sporulation of wild-type strain IH534 were inoculated into full supplemented minimal medium and processed for immunofluorescence using the procedures for Fig. 3D-F 24 hours later. Left panels, H3SP staining; middle, DAPI; right; DAPI/DIC. No staining was seen in interphase spores. Upon mitotic commitment a lumpy pattern of general chromatin staining was seen alongside some much brighter spots of H3SP staining. The number of spots of strong H3SP staining decreased with mitotic progression. During anaphase B a spot of strong staining was always seen at the extreme ends of the nuclei indicative of close proximity to the spindle pole. Towards the end of anaphase B staining generally diminished to two chromatin-associated spots. (B) Spores arising from sporulation of IH1877 were inoculated into full supplemented minimal medium. Left, H3SP; middle, DAPI; right, DAPI/DIC images of the same fields of cells. Strong H3SP staining is clearly visible in the mitotic wild-type nuclei (W) but undetectable in the stretched ark1.1 mitotic nuclei (A).
