Figure 5

The SPON2 and FGFRL1 genes are linked to CD8A in chicken and Xenopus and linked to a NITR gene cluster in medaka, zebrafish and stickleback. (a) SPON2, FGFRL1 (orange outline) and CD8A/CD8B genes (pink background) are not physically linked in human but are linked in (b) chicken and (c) Xenopus. SPON2 and FGFRL1 orthologs in (d) medaka, (e) stickleback and (f) zebrafish are not linked to CD8A/CD8B, but are linked to a NITR gene cluster. FGFRL1(1of2) and FGFRL1(2of2) in medaka and stickleback and fgfrl1a and fgfrl1b in zebrafish represent paralogs of FGFRL1. Note the expansion of CD8A-like genes in chicken [22]. Gene names and chromosomal order were identified via Contig View within the Ensembl Genome Browser [28], with the exception of Xenopus CD8B. Data were acquired using release NCBI 36 of the human genome, release 2.1 of the chicken genome, release 4.1 of the Xenopus tropicalis genome, release 1.0 of the medaka genome and release Zv7 of the zebrafish genome. The location of Xenopus tropicalis CD8B was determined by Jacques Robert and Alexander Taranin (personal communication).