Skip to main content
Fig. 5 | Genome Biology

Fig. 5

From: Role of epigenetics in unicellular to multicellular transition in Dictyostelium

Fig. 5

smcl1 overexpression is sufficient for multicellularity in D. discoideum and HdaD is an H3K27 deacetylase. a Representative pictures of D. discoideum cellular stages on KK2 plates show multicellularity delay after overexpression of smcl1 at 8, 16, 21, 25, and 41 h. Stage is displayed in the lower right hand corner. Scale bars are 20 microns. b Overexpression of smcl1 delays D. discoideum multicellularity, time to mound stage is shown in the graph on top and complete progression to fruiting body stage is shown in the graph on the bottom. Each column represents the mean ± the standard error of the mean of three biological replicates performed in triplicate. ***: p < 0.0005, ****: p < 0.0001, as assessed by unpaired t test. c Representative pictures of D. discoideum show increased size of mound (top) and fruiting body (bottom) after overexpression of smcl1. Scale bars are 20 microns. d Overexpression of smcl1 was sufficient to increase the size of mound (top) and fruiting body (bottom) diameter. Each column represents the mean ± the standard error of the mean of 54-67 D. discoideum multicellular organisms. ****: p < 0.0001 as assessed by unpaired t test. e Overexpression of smcl1 was sufficient to increase the number of cells in each fruiting body. Each column represents the mean ± the standard error of the mean of 14–15 D. discoideum fruiting bodies. ****: p < 0.0001 as assessed by unpaired t test. f Representative western blots demonstrate an increase in H3K27ac in hdaD knock-out strains. Two independent biological replicates are displayed with the upper blot probed with H3K27ac and the bottom blot probed with Histone H3 antibodies. g hdaD overexpression causes a decrease in H3K27ac as assessed by western blot. h His-tagged HdaD catalytic domain (His:HdaDcatalytic) but not GST-tagged RPA-2 is able to deacetylate lysine 27 of histones purified from Dictyostelium. This western blot is representative of 3 independent experiments. i, j Electron microscopy reveals that TSA treatment and hdaD knock-out strains have a decrease in heterochromatin. Representative images are shown (i) and quantification of 30 images (j). The scale bars represent 500 nm. % heterochromatin was calculated by examining the condensed chromatin which appears darker in the nucleus (outlined in yellow) while excluding the nucleolus (outlined in blue) from calculations. Examples of heterochromatin are marked by a red arrow. Representative images of hdaD overexpression and quantification of the nucleolus diameter in all 30 images are displayed in Additional file 1: Figure S15

Back to article page