Just like humans leave DNA in the places we inhabit, water-dwelling animals leave DNA behind in the water column. In a paper published June 3 in the journal Current Biology, scientists report that sponges, which can filter 10,000 liters of water daily, catch DNA in their tissues as they filter-feed. This proof-of-concept study identified fish, seal, and penguin DNA in sponges from the Antarctic and Mediterranean, demonstrating that sponges can be used to monitor biodiversity.
“Sponges are ideal sampling units because you find them everywhere and in every aquatic habitat, including freshwater,” says Stefano Mariani (@stefanako71), a marine ecologist and population geneticist at the University of Salford. “Also, they’re not very selective filter-feeders, they don’t run away, and they don’t get hurt by sampling – you can just grab a piece, and they will regenerate nicely.”
Additionally, the authors found that the presence of sponge DNA did not interfere with their ability to identify the DNA of other species caught within its tissue. Instead, they found that by using a particular DNA primer, which is a short sequence of nucleic acid that probes the DNA of specific organisms, they could selectively amplify vertebrate DNA while avoiding amplifying the sponge’s DNA itself.
Using this process in tandem with metabarcoding, which sorts the jumble of DNA from the tissue sample into distinguishable, species-specific piles, Mariani and his team were able to identify 31 taxa. Mostly, the species identified were fish, but one sponge sample from Antarctica included DNA from Weddell seals and chinstrap penguins. The sample was later identified to be located offshore of a penguin breeding colony. “This was a really exciting find and also makes a lot of sense,” says Mariani, “because the penguins would be in and out of the water a lot, eating, swimming, and pooing.”
Currently, machines with large water-sampling capabilities are being developed to allow scientists to sample DNA from water, but the authors think using a natural sampler could be just as effective. Because the DNA found in water is extremely diluted, it needs to undergo extensive filtering – but with filtering, Mariani warns, comes the danger of DNA contamination. Further, preserving water samples risks degrading the DNA. Sponge tissue, however, has already filtered out the water, greatly reducing both the processing time as well as the risk of contamination.
Further, bringing machines into some regions might not be feasible and may be too disruptive to fragile ecosystems. “If you want to study an endangered species of sawfish or a manatee in a mangrove forest in Mozambique, you can’t go there with massive robots. You have to use a very low-tech approach,” Mariani says.
Moving forward, the authors would like to investigate the ability of other animals to act as DNA samplers, particularly in open waters where sponges are either rare or unreachable by humans for sampling. Mariani suggests that other organisms such as jelly fish or salps, which also sieve water but float through the water column, may be more accessible in the open ocean.
Ultimately, the authors’ goal is to improve how environmental DNA is collected in order to better monitor biodiversity in areas that may not be suitable for other methods. Determining whether sponges are more effective in capturing the biodiversity of an area over pre-existing methods, however, will require further research, but the authors say this paper is the first step in answering that question. “I am hopeful that this method will prove itself to be useful,” Mariani says. “It’s the quintessential environmentally friendly biodiversity assessment tool.”
The Latest on: Environmental DNA
via Google News
The Latest on: Environmental DNA
- Clemson researchers closer to developing heat-tolerant soybeanson May 9, 2020 at 9:30 pm
Soybean is one of the top cash crops grown in South Carolina and some Clemson University researchers have helped discover an “important milestone” in developing heat-tolerant soybeans.
- Mercy, Aultman hospitals resume elective serviceson May 8, 2020 at 11:53 am
Stark County’s two largest hospitals have, on average, nine COVID-19 patients in their care. The hospitals have resumed elective procedures.
- NIST Helps Expand Genome Sequencing Of Marine Mammalson May 8, 2020 at 8:23 am
The specimens come from a longstanding project known as the National Marine Mammal Tissue Bank (NMMTB), which NIST maintains in partnership with the National Oceanic and Atmospheric Administration ...
- What Is DNA Integrity?on May 5, 2020 at 5:20 am
DNA (deoxyribonucleic acid, the genetic material found in almost all organisms) has integrity, and both integrity and stability of DNA are its key components.
- Extinguishing fearful memories depends on the flexibility of your DNAon May 4, 2020 at 8:02 am
Fear is an important survival mechanism and so too is the ability to inhibit fear when it's no longer needed. In order to counter-balance fear, the brain engages in fear extinction. In this process, ...
- Helping a Helper: Uncovering How Different Proteins Cooperate in DNA Repairon April 30, 2020 at 9:02 pm
DNA is critical for life as we know it. Ensuring that DNA is kept in a stable state is therefore important in all organisms. Although DNA faces ...
- Researchers Detect Land Animals Using DNA in Nearby Water Bodieson April 27, 2020 at 4:28 pm
Monitoring the comings and goings of aquatic life with traces of DNA in water has become an established biomonitoring technique, but scientists are now using environmental DNA to assess terrestrial ...
- This New Smartphone-Based DNA Test Could Help Track Disease in Real Timeon April 27, 2020 at 7:00 am
At the heart of the system is an “i-chip” just four cm long that includes integrated sample preparation, DNA amplification, and signal detection modules.
- Environmental DNA survey captures patterns of fish and invertebrate diversity across a tropical seascapeon April 21, 2020 at 2:21 am
Environmental DNA (eDNA) surveys show promise as a way to effectively characterize fine-scale patterns of community composition. We tested whether a single PCR survey of eDNA in seawater using a ...
- Environmental DNA (eDNA) Data Managementon April 11, 2020 at 9:37 am
The environmental DNA (eDNA) samples collected, processed, and sequenced by the Upper Midwest Environmental Sciences Center (UMESC) and partner agencies are being archived in a cloud-based database ...
via Bing News