Figure 3
Expression of TERT and its AS variants in various tissues. (a) The schematic representation of the PCR strategy for detection of OanTERT and its variants is shown. Arrows represent primers used for RT-PCR (Additional file 1: Table S1). The transcript spliced using 16 evolutionary conserved exons is designated as wild-type (WT) isoform. (b) The steady-state levels of TERT mRNA were determined by semiquantitative RT-PCR. The level of GAPDH served as a loading control. Aliquots from the PCR were taken every 5th cycle beginning with cycle 35 for the amplification of TERT and cycle 30 for GAPDH. The PCR products were resolved on agarose gels and visualized with ethidium bromide. Gray triangles indicate an increasing number of PCR cycles. (c) The expression of OanTERT AS variants was determined by RT-PCR (Additional file 1: Table S1). The position of PCR primers are shown in Figure 3a. The lower panel (7/8*) shows the PCR reaction with cDNAs obtained with synthesis using oligo-dT primer instead of random-hexamer priming. (d) The table summarizing the expression of OanTERT AS variants is shown. (e) Telomerase activity in extracts from different tissues of a male platypus (M1; lanes 1–9) and from brain, heart and skeletal muscle of three platypus females (F1, F2 and F3; lanes 11–19) was determined by the TRAP assay. All three animals evaluated were obtained from wild populations and were sexually mature adults, however, their precise age is not known. Telomerase activity in the same tissues was determined in three mouse females and one chicken female (lanes 20–31). Extraction buffer serves as the negative control (NC) (lanes 10 and 32). Molecular weights are indicated in the left margin and the positions of the amplified telomerase products (6 bp ladder starting with 50 bp band) and a 36 bp PCR internal control (IC) are shown in the right margin.