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Figure 4 | BMC Molecular Biology

Figure 4

From: Novel reference genes for quantifying transcriptional responses of Escherichia coli to protein overexpression by quantitative PCR

Figure 4

Fold changes in target gene expressions normalized using different reference gene(s) in E. Coli BL21 (DE3). Fold changes in transcript expressions of crtE (A) and dxr (B) in IPTG induced cells relative to that of control were normalized by (1) geometric mean of top three most stable genes in the temperature subgroup; (2) geometric mean of idnT, cysG, and hcaT; (3) rrsA or (4) ihfB. Normalization by rrsA falsely identified the downregulation of all target genes, and normalization by ihfB falsely identified the upregulation of all target genes. 2 is the threshold for upregulation and 0.5 is the threshold for downregulation.

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BMC Molecular Biology

ISSN: 1471-2199

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