2026-04-02 東北大学
図1. キンメモドキ
体長約7 cm。太平洋沿岸に生息し、数千匹の群れをつくる。沖縄美ら海水族館など、国内の水族館でもしばしば展示されている種ではあるが、発光することはあまり知られていない。写真: 国営沖縄記念公園（海洋博公園）：沖縄美ら海水族館。
＜関連情報＞
- https://www.tohoku.ac.jp/japanese/2026/04/press20260402-02-genome.html
- https://www.tohoku.ac.jp/japanese/newimg/pressimg/tohokuuniv-press20260402_02web_genome.pdf
- https://www.nature.com/articles/s41598-026-43942-6
盗掘タンパク質生物発光魚パラプリアカンサス・ランソネティのゲノムにおけるルシフェラーゼ遺伝子の欠損 Absence of the luciferase gene in the genome of the kleptoprotein bioluminescent fish Parapriacanthus ransonneti
Manabu Bessho-Uehara,Katsushi Yamaguchi,Keita Koeda,Shohei Matsuzaki,Taro Maeda & Shuji Shigenobu
Scientific Reports Published:01 April 2026
DOI:https://doi.org/10.1038/s41598-026-43942-6
Abstract
The metabolic and physiological functions of the living organisms are primarily governed by enzymes encoded within their own genomes. An exception to this doctrine is the phenomenon of kleptobiology, where individuals sequester and use functional modules from their prey. The fish Parapriacanthus ransonneti possesses a luciferase that catalyzes a light-emitting reaction in its light organs. Intriguingly, the protein sequence of this luciferase is identical to that of the ostracod-derived luciferase. We recently demonstrated that the fish sequesters and retains the luciferase from the luminous prey, leading to the hypothesis that the fish does not have a gene encoding the luciferase. To test this hypothesis, here, we produced a high-quality draft genome of P. ransonneti. The assembled size of 625 Mbp closely matches the experimentally estimated genome size of 613 Mbp, and we constructed a gene model with a high BUSCO score. Our search within this gene model did not detect any ostracod-type luciferase genes. Expanding our search to include the entire assembled genome, raw reads, and the transcriptome also supported the absence of the luciferase genes. These results suggest that P. ransonneti lacks the luciferase gene, supporting our previous discovery that it utilizes stolen proteins for bioluminescence.
