Fig. 2. Immunolocalisation of DmSMC4 and Barren in control and DmSMC4-depleted Drosophila S2 cells. In control cells during prometaphase and anaphase DmSMC4 and Barren co-localise to an axial structure of sister chromatids. After depletion of DmSMC4 by dsRNAi, chromosomal-associated DmSMC4 is significantly reduced after 48 hours and undetectable after 96 h. A reduction in the level of chromatin-associated DmSMC4 causes the formation of short chromosomes with unseparated sister chromatids and a highly abnormal distribution of Barren. In cells that show no DmSMC4 staining, chromosomes are short, no defined sister chromatids are observed and Barren is undetected. Scale bars: 5 µm.