Figure 2

Viewing sequences and position numbering of associated regional segments. a) The Exon 1/Exon 2 splice junction of transcript 1 (SP1) alongside the translated sequence. Annotated regions have the colour highlights. Colours red, green, and aqua, respectively, refer to a putative signal peptide, an Epidermal Growth Factor domain, and the splice site junction between Exon 1/Exon2. b) The three varieties of 5'UTRs ([GenBank: NM_080591.1] and two computationally derived alternate splice variants from AltSplice [32]) aligned to the PTGS1 gene sequence (main sequence). Alternate 5' sequences can occur due to differential regulation of upstream promoters and splicing factors, giving rise to different transcription-start sites and splice donor/or acceptor sites [21, 33]. Mfold program [34] predicts a hair-pin RNA secondary structure within 5' UTR(a), represented in red. Secondary structures in the 5'UTR can modulate translation efficiency.