Multiple Cypridina Luciferase Genes in the Genome of Individual Ostracods, Vargula hilgendorfii (Cypridina hilgendorfii)

The genomic structure of the Cypridina luciferase gene in Vargula hilgendorfii (formerly Cypridina hilgendorfii) was determined with three lambda phage clones (lambda 34, lambda 45, and lambda 61). The luciferase genes in clones lambda 34 and lambda 61 consisted of 13 exons and 12 introns, and clone lambda 45 only contained exons 1-5. The splicing sites of the luciferase genes in lambda 34 and lambda 61 were conserved completely with the consensus sequence. The translated luciferases had 555 amino acid residues, which were over 98.6% identical to those of cDNA clones as previously reported. In contrast, each intron in clones lambda 34, lambda 45, and lambda 61 varied significantly in length. To explain the variation of intron length among the three V. hilgendorfii luciferase genes, genomic DNA was isolated from a single V. hilgendorfii specimen, and the regions from exon 1-3 of the luciferase gene were amplified by polymerase chain reaction (PCR). PCR products with various lengths were detected and were confirmed as the luciferase gene fragments by Southern blot analysis. Furthermore, DNA sequence analysis indicated that at least seven luciferase gene groups might be present in the genome of a single specimen. Thus, multiple Cypridina luciferase genes exist in the genome of a single V. hilgendorfii specimen.

Automated summary

The genomic structure of the Cypridina luciferase gene in Vargula hilgendorfii was found to contain multiple exons and introns, with conserved splicing sites but varying intron lengths. PCR amplification and DNA sequence analysis revealed the presence of multiple luciferase gene groups in the genome of a single V. hilgendorfii specimen.