Examination of known somatic cell B-Myb target gene expression patterns following knockdown of B-Myb in ESCs.

<p>A) Western blot and graphic presentation of Cyclin B1 (Ccnb1) protein expression following knockdown of B-MYB by shRNAs 1, 2 and 5. B) RNA (left) and protein (right) analysis of the B-MYB target gene Polo-like kinase 1 (Plk1) following Bγ-Myb KD with shRNA1 and shRNA5. The effects of B-MYB KD on Plk1 RNA were transient; however, the loss of RNA led to a significant and sustained decrease in its protein abundance. C) Western blot and bar graph showing the abundance of selected proteins following knockdown of B-MYB and CCNB1 using shRNAs and microRNAs, respectively. D) Reduced expression of CCNB1 could not mimic the cell cycle related defects associated with B-MYB deficiency, such as monopolar or multipolar centrosomes as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0042350#pone-0042350-g001" target="_blank">Figure 1</a>. Ctl – control; KD – Knockdown; NS- non-silencing. *, p<0.05. Data are expressed as mean ± standard deviation (SD).