Comparison of novel human and putative murine ghrelin exon sequences. The mouse and human alignments were generated by the ClustalW program and drawn by BOXSHADE http://www.ch.embnet.org/software/BOX_form.html. Black shading indicates conserved nucleotides. Transcription start sites determined by 5' RACE (Δ) and CAGE (Cap Analysis of Gene Expression) (*) are indicated, and the exact transcription start site nucleotides are shaded in grey in each species. Exon-intron boundaries are indicated by lowercase letters and bold font. A. Comparison of human and putative mouse transcription start sites (TSSs) in the novel exon -1. Two human TSSs are indicated, corresponding to 106 bp (5' RACE and CAGE tag starting site T03R009D4FFF) and 92 bp exon -1. An initiating methionine (ATG, start codon) which is not followed by a stop codon in exon -1 is underlined. No murine exon -1 CAGE tags were found in the FANTOM3 Basic CAGE viewer (May 2007) B. Comparison of human and mouse extended exon 0 sequences showing several human and murine exon 0 transcription start sites deduced by 5' RACE and CAGE (mouse T06R06CF33DC, T06R06CF32CB and T06R06CF3202). The originally described 20 bp exon 0 transcription start site, present in both human and murine ghrelin transcripts, is indicated by a pound mark (#).