Figure 1.

(A) Organization of the jRXR gene and cDNA isoforms. A full length cDNA was obtained by PCR with primers based on the previously determined 5′ and 3′ ends of the cDNA. Three isoforms of cDNA alternatively spliced in the region 5′ to the DBD were sequenced. Two genomic clones indicated by solid lines were obtained by screening in a genomic library. Regions indicated by triangles connected by dashed lines were amplified by PCR from genomic DNA prepared from male gonads. The size of the transcript was confirmed by RNA primer extension. The position of intron 1 was derived from cDNA isoforms, although we failed to amplify this intron from genomic DNA by PCR. The presence of intron 4 and 5 is determined by PCR from genomic DNA. (B) Southern blot analysis of genomic DNA prepared from gonads of 21 male adult jellyfish. DNA restricted by EcoRI and probed by cDNA probe covering exon 3 yielding two bands of 2.5 and 3 kb.