Heatmap for individual reference genes expression.

<p>The relative gene expression levels of all samples were depicted in color-code. The threshold cycle value of each sample was normalized against that of all the reference genes. Expression levels of all samples were normalized against those of 1 d GM group respectively and log₂ transformed. Sixteen reference genes were sorted from up to down by their geNorm M value. Red color indicated that the expression level of gene was up-regulated compared to that of 1 d of GM group (the brighter the higher), whereas green color indicated vice versa (the brighter the lower).