MBARI (Monterey Bay Aquarium Research Institute) | Bioluminescence in the deep sea: Glow-in-the-dark corals light up the deep ocean @MBARIvideo | Uploaded July 2020 | Updated October 2024, 4 hours ago.
A team of MBARI researchers filmed bioluminescence from a variety of deep octocorals (soft corals, sea pens, and gorgonians) in their own habitat for the first time. The scientists worked with the pilots of the remotely operated vehicle (ROV) Doc Ricketts to equip the vehicle with an extremely light-sensitive video camera. Since many animals only glow when disturbed, they filmed the animals while gently touching them with the ROV’s manipulator arm or a soft paint brush. They found that many of the most common deep-sea corals can create their own light, including several groups not previously known to glow. The researchers also analyzed the animals’ DNA to look for the genes that might be creating the luminescence.
Most glowing animals produce light by combining a light-producing chemical, luciferin, and a protein, luciferase. Many of the deep-sea corals examined contained a type of luciferin called coelenterazine, and they all contained a form of luciferase that reacts with coelenterazine (and oxygen) to produce blue light. However, some sea pens described in this study gave off a greenish glow. This is because they also contain green fluorescent protein (GFP). GFP absorbs the blue light produced by the luciferin-luciferase reaction and re-emits it as green light. GFP is known to be an effective biomedical tracer used, for example, in tracking diseases. GFP is found in a wide assortment of shallow corals and jellies as well, suggesting that octocorals evolved the ability to glow very early in their evolutionary history.
In addition to the deep-sea corals, the researchers also examined a flytrap anemone—a bright orange deep-sea anemone that grows to nearly a foot across. They discovered that this animal can emit a cloud of brightly glowing blue slime from its mouth (located in the center of its circular body).
This study demonstrates how important bioluminescence is to many deep-sea animals. Exactly why these animals glow remains a mystery, but glowing waves of light or a burst of glowing slime might function to startle or confuse potential predators in the dark deep ocean. Human activities that reduce water clarity, such as deep-sea mining, could impact these seafloor ecosystems in ways we might not expect.
Video production team: Manabu Bessho-Uehara, Ben Erwin, Steve Haddock, Kyra Schlining, Susan von Thun
Video editor: Kyra Schlining
Music: Touch the Future (MotionArray)
More on this story: mbari.org/glowing-corals
Publication referenced:
M. Bessho-Uehara, W.R. Francis, and S.H.D. Haddock (2020). Biochemical characterization of diverse deep-sea anthozoan bioluminescence systems. Marine Biology 167: 114.
doi.org/10.1007/s00227-020-03706-w
More on bioluminescence and fluorescence:
youtu.be/whbeFXFZqiU
mbari.org/new-study-shows-that-three-quarters-of-deep-sea-animals-make-their-own-light
Follow MBARI on social media:
Facebook: facebook.com/MBARInews
Twitter: twitter.com/MBARI_News
Instagram: instagram.com/mbari_news
Tumblr: mbari-blog.tumblr.com
LinkdIn: linkedin.com/company/monterey-bay-aquarium-research-institute-mbari-
A team of MBARI researchers filmed bioluminescence from a variety of deep octocorals (soft corals, sea pens, and gorgonians) in their own habitat for the first time. The scientists worked with the pilots of the remotely operated vehicle (ROV) Doc Ricketts to equip the vehicle with an extremely light-sensitive video camera. Since many animals only glow when disturbed, they filmed the animals while gently touching them with the ROV’s manipulator arm or a soft paint brush. They found that many of the most common deep-sea corals can create their own light, including several groups not previously known to glow. The researchers also analyzed the animals’ DNA to look for the genes that might be creating the luminescence.
Most glowing animals produce light by combining a light-producing chemical, luciferin, and a protein, luciferase. Many of the deep-sea corals examined contained a type of luciferin called coelenterazine, and they all contained a form of luciferase that reacts with coelenterazine (and oxygen) to produce blue light. However, some sea pens described in this study gave off a greenish glow. This is because they also contain green fluorescent protein (GFP). GFP absorbs the blue light produced by the luciferin-luciferase reaction and re-emits it as green light. GFP is known to be an effective biomedical tracer used, for example, in tracking diseases. GFP is found in a wide assortment of shallow corals and jellies as well, suggesting that octocorals evolved the ability to glow very early in their evolutionary history.
In addition to the deep-sea corals, the researchers also examined a flytrap anemone—a bright orange deep-sea anemone that grows to nearly a foot across. They discovered that this animal can emit a cloud of brightly glowing blue slime from its mouth (located in the center of its circular body).
This study demonstrates how important bioluminescence is to many deep-sea animals. Exactly why these animals glow remains a mystery, but glowing waves of light or a burst of glowing slime might function to startle or confuse potential predators in the dark deep ocean. Human activities that reduce water clarity, such as deep-sea mining, could impact these seafloor ecosystems in ways we might not expect.
Video production team: Manabu Bessho-Uehara, Ben Erwin, Steve Haddock, Kyra Schlining, Susan von Thun
Video editor: Kyra Schlining
Music: Touch the Future (MotionArray)
More on this story: mbari.org/glowing-corals
Publication referenced:
M. Bessho-Uehara, W.R. Francis, and S.H.D. Haddock (2020). Biochemical characterization of diverse deep-sea anthozoan bioluminescence systems. Marine Biology 167: 114.
doi.org/10.1007/s00227-020-03706-w
More on bioluminescence and fluorescence:
youtu.be/whbeFXFZqiU
mbari.org/new-study-shows-that-three-quarters-of-deep-sea-animals-make-their-own-light
Follow MBARI on social media:
Facebook: facebook.com/MBARInews
Twitter: twitter.com/MBARI_News
Instagram: instagram.com/mbari_news
Tumblr: mbari-blog.tumblr.com
LinkdIn: linkedin.com/company/monterey-bay-aquarium-research-institute-mbari-
