Takifugu rubripes


Takifugu rubripes, commonly known as the Japanese puffer, Tiger puffer, or torafugu, is a pufferfish in the genus Takifugu. It is distinguished by a very small genome that has been fully sequenced because of its use as a model species and is in widespread use as a reference in genomics.

Taxonomy and etymology

The species is often referred to in the genomics literature as Fugu rubripes. The genus Fugu is a synonym of the currently preferred Takifugu. Takifugu is Japanese for puffer and rubripes comes from the Latin ruber and pēs meaning ruddy foot.

Distribution and habitat

The species is known from the Sea of Japan, East China Sea and Yellow Sea north to southern Sakhalin, at depths of. It is a demersal species. Spawning occurs in estuaries; young fish can tolerate a wide range of salinities and will remain in river mouths and lagoons, maturing for one year before migrating permanently to the open ocean.

Genome

A feature of this species is that it has a very small genome, which is used as a ‘reference’ for identifying genes and other elements in human and other vertebrate genomes. The genome was published in 2002 by the International Fugu Genome Consortium via whole genome shotgun sequencing. After being initiated in 1989, it was the first vertebrate genome after the human genome to be made publicly available. It remains among the smallest known vertebrate genomes; its number of base pairs is ~6% and the number of previously known protein-coding genes ~13% that of the human genome, although the number of chromosomes is comparable to that of humans. This makes it particularly useful for comparative studies. Current estimates show a total of 392,376,244 base pairs, 1,138 known and 18,093 novel protein-coding genes, and 593 RNA genes.

Toxicity

As some other pufferfish, some organs of the Japanese puffer contain tetrodotoxin and are highly toxic. The toxin is highly concentrated in liver and ovaries, slightly present in the intestines and flesh, and absent from skin and testes.

Conservation

The Japanese puffer is classified as Near Threatened by the IUCN. It is one of the most valuable commercial fishes in Japan, and although current catches are small compared to those of many other commercial species such as sardines and anchovy, they appear to be unsustainable and prevent the recovery of the species from earlier over-exploitation. Gear restrictions and adjustments of fishery seasons to protect juveniles have been recommended to aid recovery. The species is extensively raised in aquaculture.

Internet popularity

In 2019, a video by Korean youtuber Yummyboy of a Japanese puffer became a viral internet meme. In the video, a puffer is fed a carrot to demonstrate their strong bite, and then proceeds to say "aeugh." The fish is then killed and prepared into fugu.