Fig. 3

The effects of types of host bacteria and culturing temperature of the bacteria on yield of AluY RNAs. a Effects of types of BL21 host bacteria on yield of AluY RNAs. The left panel shows the result of northern detection. pET-AluY × 8 plasmid was transformed into three kinds of BL21 cells, including DE3, BMBL21-DE3-pLysS (pLysS) and Trans BL 21 (TransBL), northern blotting showed that the yield of AluY RNAs was the highest when using pET-AluY × 8 DE3; the right panel shows the dyeing results of methylene blue; b IOD values of each lane of the northern blotting results (means of three independent experiments) of types of BL21 host bacteria on yield of AluY RNAs. “*”, the AluY RNAs yield was the highest using DE3 engineering bacteria and was significantly higher than that of other bacteria (p < 0.01). c Effects of culturing temperature of pET-AluY × 8 DE3 bacteria on yield of AluY RNAs. The left panel shows the results of northern blotting. pET-AluY × 8 DE3 bacteria were cultured at 34, 37 or 40 °C and then were induced by IPTG for 4 h, we found AluY RNAs yield was the highest under the 37 °C cultivation; the right panel shows the dyeing result of methylene blue; d IOD values of each lane of the northern blotting results of effects of culturing temperature (means of three independent experiments). “*”, the AluY RNA yield was the highest under the 37 °C cultivation and was significantly higher than that of other temperature (p < 0.01)