Tissue-specific transcriptional expression of H2A.Z and H2A.Z.7 . (A) RT-PCR analysis of H2A.Z.7, H2A.Z and 16S mitochondrial rRNA (16S) from brain, pituitary, liver, testis and gills tissues from summer- and winter-acclimatized carp. Three different fish for each season were examined (S1, S2, S3 and W1, W2, W3). The last line (−) corresponds to the negative control of PCR reaction. (B) The graph shows a relative quantification of tissue-specific transcriptional expression of H2A.Z subtypes. Orange bars denote H2A.Z.7 and black bars represent the content of the remaining H2A.Z subtypes, respectively. All bars represent the ratio between the respective mRNA and carp 16S mitochondrial rRNA as a control. S, summer; W, winter.