Genomic structure of SYBL1 and domain architecture of VAMP7. Top: exon-intron structure of the human gene SYBL1 (AJ004799). The 100 bp reference bar (blue, top left) only refers to exons; introns are not to scale. Exons are numbered: coding regions are white and non-coding ones are grey; start (green arrow) and stop (red circle) codons are indicated. Bottom: domain architecture of the encoded protein VAMP7 (P51809): Longin domain (red), SNARE motif (cyan; the black vertical bar indicates the conserved arginine of the polar layer) and transmembrane region (light green) with intravesicular tail (thin light green line).