Figure 4.

PLL both improves the efficiency of adenoviral-Cre-mediated deletion of a floxed allele in primary osteoblasts and BMSCs from Gja1^fl/fl mice and recapitulates the expected biological responses to Cx43 gene deletion at low MOI. Quantitative real time RT-PCR of the expression of the Gja1 allele in (a) primary mouse osteoblasts or (b) primary mouse BMSCs 72 h post transduction with a Cre recombinase-encoding adenovirus (Cre) or a negative control GFP-encoding adenovirus (Ad-GFP) at the indicated MOIs in the presence or the absence of PLL. (c). Westerns blot of Cx43 expression in whole cell extracts from primary osteoblasts or BMSCs from Gja1^fl/fl mice that had been transduced with GFP (negative control) or Cre recombinase expressing adenovirus (MOI=5, respectively) in the presence of PLL. The multiple bands observed are due to the multiple phosphorylation states of Cx43. (d) Quantitative real time RT-PCR of the expression of osteoblasts genes in BMSCs differentiated for 7 days post transduction with GFP (negative control) or Cre recombinase expressing adenovirus (MOI=5) in the presence of PLL. All histograms represents means±s.d. and *P<0.05. #, indicates P<0.05 relative to the GFP transduced control; ##, indicates P<0.05 relative to the GFP transduced control and the corresponding –PLL sample. GFP, green fluorescence protein; MOI, multiplicities of infection; PLL, poly-l-lysine; RT-PCR, reverse transcription–PCR.