Ed with anti-GFP or anti-b-actin antibodies (Abcam). Immuno-reactive proteins were visualized using the Odyssey Infrared Imaging System and relatively quantified by densitometric analysis (Li-Cor, Lincoln, NE), as described by the manufacturer.Western BlottingTotal proteins were extracted from tail tips or other tissues. Frozen samples were ground to powder by pestle and Rubusoside web mortar grinding and solubilized in a solution of 62.5 mM Tris pH6.8, 10 glycerol, 2.5 sodium dodecyl sulfate (SDS), and HaltTMProtease Inhibitor Cocktail (Thermo Scientific). Quantification of total protein was carried out by Bicinchoninic acid assay with BSA (Sigma-Aldrich). The proteins (100 mg) were subjected to 12Bisulfite SequencingThe genomic DNA was extracted from tail tips or other tissues by DNeasy@ Blood Tissue Kit (QIAGEN) according to the instruction manual. Bisulfite modification was performed with 0.6 mg of DNA for each sample using the EpiTect@Bisulfite Kit (QIAGEN) according to the instruction manual. PCR primers used to amplify the CMV promoter were designed by MethPrimer software online (http://www.urogene.org/methprimer/), whichGeneration of Transgenic Sheep by LentivirusFigure 5. Correlation of CMV promoter methylation status with GFP expression level of transgenic sheep. (A) Schematic of pLEX-EGFP vector. (B) Status of the CMV promoter methylation in 8 transgenic sheep. The 487bp sequences of CMV promoter containing one CpG islands were targeted for methylation analysis. Genomic DNAs extracted from 8 transgenic lambs (#4?2) were treated with bisulfite and sequenced at least 7 clones for each sample. (C) Status of the CMV promoter methylation in tested tissues of two anatomized lambs (#4 and #12). Genomic DNAs extracted from tail tips, liver, lung, kidney and spleen were treated with bisulfite and sequenced at least 7 clones for each sample. The black cycles represented the methylated CpG and the white cycles represented the non-methylated CpG. (D) Correlation of GFP expression with methylation level of lentiviral CMV promoter of transgenic lambs. Densitometric quantification of the relative GFP expression was assayed by Western blotting (Fig. 3B) in tail tips of transgenic lambs #4?4 (up panel). Methylation levels were measured by the average ratios of methylated CpGs to total CpGs of the Oltipraz target CMV promoter sequence (middle panel). Correlation of the methylation levels of CMV promoter with GFP expression of 8 transgenic sheep was analyzed (low panel). (E and F) Correlation of GFP expression with methylation levels of CMV promoter in tested tissues of anatomized lambs (#4 and #12). Densitometric quantification of the relative GFP expression was assayed by Western blotting (Fig. 4B) in tissues of #4 (E, up panel) and #12 (F, up panel) lamb. Methylation levels of CMV promoter in tested tissues of #4 (E, middle panel) and #12 (F, middle panel ) lambs were based on Fig. 5C. The average rate of methylated CpGs in the 487 bp region of CMV promoter was defined as the indicator of methylation status. Correlation of methylation levels of CMV promoter with GFP expression levels was analyzed in tested tissues of #4 (E, low panel) and #12 (F, low panel) lambs. doi:10.1371/journal.pone.0054614.gwas also used to predict CpG site and CpG islands. The following PCR primers were used to amplify a 487-bp fragment containing one CpG islands with 30 CpGs: forward 59-GGGTTATTAGTTTATAG TTTATATATGG-39 and reverse 59-GATTCACTAAACCAACTCTACTTA-39. The PCR of bisulfite-modi.Ed with anti-GFP or anti-b-actin antibodies (Abcam). Immuno-reactive proteins were visualized using the Odyssey Infrared Imaging System and relatively quantified by densitometric analysis (Li-Cor, Lincoln, NE), as described by the manufacturer.Western BlottingTotal proteins were extracted from tail tips or other tissues. Frozen samples were ground to powder by pestle and mortar grinding and solubilized in a solution of 62.5 mM Tris pH6.8, 10 glycerol, 2.5 sodium dodecyl sulfate (SDS), and HaltTMProtease Inhibitor Cocktail (Thermo Scientific). Quantification of total protein was carried out by Bicinchoninic acid assay with BSA (Sigma-Aldrich). The proteins (100 mg) were subjected to 12Bisulfite SequencingThe genomic DNA was extracted from tail tips or other tissues by DNeasy@ Blood Tissue Kit (QIAGEN) according to the instruction manual. Bisulfite modification was performed with 0.6 mg of DNA for each sample using the EpiTect@Bisulfite Kit (QIAGEN) according to the instruction manual. PCR primers used to amplify the CMV promoter were designed by MethPrimer software online (http://www.urogene.org/methprimer/), whichGeneration of Transgenic Sheep by LentivirusFigure 5. Correlation of CMV promoter methylation status with GFP expression level of transgenic sheep. (A) Schematic of pLEX-EGFP vector. (B) Status of the CMV promoter methylation in 8 transgenic sheep. The 487bp sequences of CMV promoter containing one CpG islands were targeted for methylation analysis. Genomic DNAs extracted from 8 transgenic lambs (#4?2) were treated with bisulfite and sequenced at least 7 clones for each sample. (C) Status of the CMV promoter methylation in tested tissues of two anatomized lambs (#4 and #12). Genomic DNAs extracted from tail tips, liver, lung, kidney and spleen were treated with bisulfite and sequenced at least 7 clones for each sample. The black cycles represented the methylated CpG and the white cycles represented the non-methylated CpG. (D) Correlation of GFP expression with methylation level of lentiviral CMV promoter of transgenic lambs. Densitometric quantification of the relative GFP expression was assayed by Western blotting (Fig. 3B) in tail tips of transgenic lambs #4?4 (up panel). Methylation levels were measured by the average ratios of methylated CpGs to total CpGs of the target CMV promoter sequence (middle panel). Correlation of the methylation levels of CMV promoter with GFP expression of 8 transgenic sheep was analyzed (low panel). (E and F) Correlation of GFP expression with methylation levels of CMV promoter in tested tissues of anatomized lambs (#4 and #12). Densitometric quantification of the relative GFP expression was assayed by Western blotting (Fig. 4B) in tissues of #4 (E, up panel) and #12 (F, up panel) lamb. Methylation levels of CMV promoter in tested tissues of #4 (E, middle panel) and #12 (F, middle panel ) lambs were based on Fig. 5C. The average rate of methylated CpGs in the 487 bp region of CMV promoter was defined as the indicator of methylation status. Correlation of methylation levels of CMV promoter with GFP expression levels was analyzed in tested tissues of #4 (E, low panel) and #12 (F, low panel) lambs. doi:10.1371/journal.pone.0054614.gwas also used to predict CpG site and CpG islands. The following PCR primers were used to amplify a 487-bp fragment containing one CpG islands with 30 CpGs: forward 59-GGGTTATTAGTTTATAG TTTATATATGG-39 and reverse 59-GATTCACTAAACCAACTCTACTTA-39. The PCR of bisulfite-modi.