Photo credit: www.sciencedaily.com
Recent advancements in DNA probe technology are transforming the study of squids and octopuses in the depths of the ocean. Researchers from Kobe University have introduced a powerful new method for marine ecological research and conservation, facilitating a better understanding of these enigmatic creatures.
Cephalopods, which include squids and octopuses, play a pivotal role in marine ecosystems, acting as both predators and prey. “These organisms are vital for the transfer of energy and nutrients in the marine food web,” states marine ecologist WU Qianqian from Kobe University. To effectively study these species, especially given the challenges posed by their deep-sea habitats, it is essential to understand their distribution. Wu highlights the vastness of the deep sea, noting, “This part of our planet remains largely unexplored and is inhabited by countless organisms whose ecological roles are still unknown.”
To tackle this challenge, Wu and her team developed an innovative detection system that analyzes environmental DNA. Their methodology, referred to as “environmental DNA metabarcoding,” involves targeting specific DNA fragments from the environment, akin to angling with precise bait for desired fish. The major hurdle was to design probes that were precise enough to focus on specific cephalopod groups while remaining broad enough to capture various species within those groups. Wu praises her lab’s established expertise in environmental DNA and their collaboration with the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), expressing that their combined efforts focused on the efficient collection of deep-sea samples.
In a recent publication in the journal Marine Environmental Research, the research team announced their success in developing DNA primers that can specifically detect a wide array of cephalopod species. Their trials demonstrated effectiveness with both mock samples sourced from the Osaka Museum of Natural History and actual seawater samples collected from the surface to depths of 2,000 meters. Remarkably, this milestone marks the first reliable detection of certain cephalopod species in Japanese waters, underscoring the technique’s robustness. A pivotal factor in their approach was the choice to target longer DNA fragments, which, while prone to quicker degradation, maintains viability in cold deep-sea environments, allowing for more accurate species representation.
Notably, the research revealed octopus DNA exclusively in the deepest samples. Based on their controlled trials, the team deduced that this finding is not a failure of their detection method but rather an insight into the lifestyle of octopuses, which tend to be reclusive, ground-dwelling creatures. “Future investigations will necessitate adjustments in sampling strategies to better align with the behavioral and life history patterns of various cephalopods,” Wu remarks. She also emphasizes the need to address potential misidentifications stemming from DNA database inaccuracies, aiming to enhance cooperation between molecular biologists and taxonomists.
Wu concludes, “Our technique is set to pave new pathways for deep-sea cephalopod studies and will support marine conservation efforts.”
This research received funding from the Ministry of Environment of Japan and was conducted in partnership with Kyoto University, the Osaka Museum of Natural History, the Natural History Museum and Institute, JAMSTEC, and the Okinawa Churashima Foundation.
Source
www.sciencedaily.com