Survival of Deep-Sea Shrimp (Alvinocaris sp.) During Decompression and Larval Hatching at Atmospheric Pressure

Abstract

We report successful larval hatching of deep-sea shrimp after decompression to atmospheric pressure. Three specimens of deep-sea shrimp were collected from an ocean depth of 1157 m at cold-seep sites off Hatsushima Island in Sagami Bay, Japan, using a pressure-stat aquarium system. Phylogenetic analysis of Alvinocaris sp. based on cytochrome c oxidase subunit gene sequences confirmed that these species were a member of the genus Alvinocaris. All 3 specimens survived to reach atmospheric pressure conditions after stepwise 63-day decompression. Two of the specimens contained eggs, which hatched after 10 and 16 days, respectively, of full decompression. Although no molting of the shrimp larvae was observed during 74 days of rearing under atmospheric pressure, the larvae developed conventional dark-adapted eyes after 15 days.

Cell biology of deep-sea multicellular organisms

“…In the vesicomyid clam C. soyoae, spawning was synchronized with natural temperature (Momma et al 1995) and induced by an artificial temperature increment of in situ water using the submersible Shinkai 2000 carrying a polycarbonate dome with a halogen light (Fujiwara et al 1998). Using the piezostat aquarium system, we investigated whether gametogenesis is induced in abyssal organisms by alterations in exterior environmental factors such as pressure, temperature, and/or artificial light exposure (Koyama et al 2005a).…”

“…were collected using a trap with the piezostat aquarium system (Figs. 1 and 2) from an ocean depth of 1,157 m at cold-seep sites off Hatsushima Island in Sagami Bay, Japan (Koyama et al 2005a). The deepsea shrimp were maintained at a temperature of 4.5°C with fluctuation of ±0.3°C at hydrostatic pressure of 11.5 MPa (corresponding to a depth of 1,130 m).…”

“…There are three major obstacles to molecular and cellular biological studies of deep-sea multicellular organisms under atmospheric pressure. The first is the development of devices for capturing and maintaining them, because most succumb as a result of decompression and exposure to the high-temperature surface seawater (Koyama and Aizawa 2000;Koyama et al 2002Koyama et al , 2005a. The second is acclimation of the captured organisms to atmospheric conditions.…”

Piezotolerance of the cytoskeletal structure in cultured deep-sea fish cells using DNA transfection and protein introduction techniques

“…There are three major obstacles in molecular and cellular biological studies of deep-sea multicellular organisms under atmospheric pressure. The first is the development of devices for capturing and maintaining them, because most succumb as a result of decompression and exposure to the hightemperature surface seawater (Koyama and Aizawa 2000;Koyama et al 2002Koyama et al , 2005b. The second is acclimation of the captured organisms to atmospheric conditions.…”

“…The third is cells from deep-sea animals and the cryopreservation of these cells under atmospheric conditions. S. Koyama (&) Extremobiosphere Research Center, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushimacho, Yokosuka 237-0061, Japan e-mail: skoyama@jamstec.go.jp M. Aizawa Tokyo Institute of Technology, O-okayama, Japan In our previous studies, we solved those problems by developing a novel piezostat aquarium system to capture and maintain deep-sea organisms (Koyama et al 2002(Koyama et al , 2003a(Koyama et al , 2003b(Koyama et al , 2005b. Using this system, the deep-sea fish Simenchelys parasiticus (habitat depth, 366-2,630 m; Nakabo 2000) captured from an ocean depth of 1,162 m survived under atmospheric pressure for 5 days after gradual, slow decompression (Koyama et al 2003a(Koyama et al , 2003b.…”