Bovine RTEL is alternatively spliced in both coding sequence and 5' untranslated region (5'UTR). Three splice variants were identified in cDNA from multiple adult tissues, two 5'UTR isoforms were obtained by 5'RACE from testis. A. Agarose gel electropherograms of the splice variants from various tissues developed by RT-PCR, line 1 to 7 presents lung, liver, pancreas, cardia, testis, ovary and spleen respectively. The arrows indicate the splice variant correspond to each band. B. Two forms of 5'UTR. The rectangles indicate the genomic regions that identical to the 5'UTR (not to scale), putative exonic and intronic regions are indicated by filled and opened rectangles, GT-AG splicing sites were also shown. Skipping of full or partial exons is presented by brackets above or below according to different forms. Numbers on the right shows the frequency to observe a given 5'UTR isoforms. C. Splice variants in coding region. Number labelled boxes indicate the genomic regions identical to cDNA (exons 29 to 35). Regularly and alternatively spliced exons are shown by black and grey boxes respectively below. SV is short for splice variants and Full means the full-length transcript. Numbers on the right shows the times an splice variant presents in the sequenced RTEL transcripts from indicated tissues. D. Amino acids changes caused by alternative splicing. The alignment figures display the changes at the protein level of three identified splice variants (SV-1 to SV-3) compared to full-length protein, identical residues are shown in black background whereas changed are indicated by grey.