The Lab Aquatic
The Lab Aquatic
August 31, 2016
August 30, 2016
If you have been around the third floor of wing A in Biodesign lately, you have probably noticed the new 100-gallon saltwater aquarium. This may bring some welcome stress relief to the workplace as the new school year gets underway. The real purpose of the aquarium though, is purely scientific.
Associate professor Carlo Maley of the Biodesign Institute Center for Personalized Diagnostics recently had the aquarium set up in his new lab space with snails, shrimp and crabs, followed later by clownfish, gobies and anemones. But these are just the supporting cast. The main character in the aquarium is actually more like SpongeBob than Nemo.
Professor Maley told me more about his recent fascination with sponges.
“In a survey of cancer across species, we noticed that no one had reported cancer in sponges. We don't know if that is because no one has studied cancer in sponges or if sponges are particularly cancer resistant. So we have set out to grow sponges in our aquarium to answer that question.”
First, the sponges will be exposed to cancer-causing agents, followed by a check for abnormal cell growth under the microscope. Next, with DNA sequencing and computational tools, the research team will probe for any cancer fighting responses that the organisms may employ.
Understanding how multicellular animals deal with cancer can inform efforts in preventing and treating cancer in humans, since we share many of the same genes. One such gene is called p53, which detects and suppresses the growth of early cancer cells. Prof. Maley found in his previous work that elephants have 40 copies of this gene (we humans have only two). This helps explain what is known as Peto’s Paradox – the observation that in spite of having more cells, larger animals are not proportionally more prone to developing cancer.
This zoo-like curating of cancer clues across species to better understand the evolution of cancer is known as comparative oncology. Prof. Maley collaborates with assistant professor Athena Aktipis from the Center for Evolution and Medicine to explore the big questions in this field. Prof. Aktipis brings her unique perspective that stems from her study of the phenomena of cooperation as it applies to human behavior, microbes, or in this case, multicellular systems. You can read more about how cellular cooperation (or the lack thereof) relates to cancer throughout the tree of life here in a review by Aktipis, Maley, and other colleagues.
Some of the other organisms that the Maley Lab is looking at may likewise be able to evade cancer. That includes tiny flatworms (Macrostomum lignano), which are remarkably capable of regeneration and serve as model organisms for stem cell research; and placozoa (Trichoplax adhaerens), which are among the simplest of multicellular organisms having only six cell types.
Research scientist Angelo Fortunato showed me how these organisms look under the microscope. Fortunato is an expert in evolutionary biology as well as cancer genetics, and has years of research experience working with various other model organisms from amoebas to mice. Assisted by undergraduate researchers Michelle Culbertson and Rachel Geiser, he has been responsible for setting up the aquarium and incubators and bringing life to the Maley Lab.
Keeping the sponges alive and healthy is no simple task. The aquarium is a sophisticated piece of lab equipment, with filters, lighting, and regulators that run behind the scenes to support a healthy balance of microbes and algae. Fortunato elaborated on why he takes a symbiotic approach to cultivating sponges.
“In order to survive, the organisms of the aquarium require complex ecological interactions. Often they develop mutualistic or symbiotic relationships with bacteria and algae. Many of these ecological interactions are not well known and difficult to reproduce. So, the best way to culture the sponges is to recreate a natural habitat.”
The fish in the aquarium are content to eat commercial fish food provided by an automatic dispenser (feeding time is 1:30 pm, by the way). But the sponges require a diet that better suits their place on the food chain.
“The sponges are filter feeders so the main aquarium will provide part of the food. The sponges can ingest only food particles of about 5-25 microns and the commercial foods have larger size particles, so they are not able to ingest the commercial food as it is. Anyway, we prepare a ‘home made’ food of the right size to integrate the diet of the sponges,” Fortunato explained.
If you have not yet had a chance to visit the aquarium, go check it out. You won’t find the sponges quite yet, but there are several small ones waiting backstage in a connected holding tank until they are ready to make their appearance on the aquarium’s main stage in a month or so.
In the meantime, see if you can identify the rest of the cast.
Here below is the full list:
- Marine Sponge, Tethya wilhelma
- Clownfish, Amphiprion ocellaris (Frodo and Sam)
- Firefish Goby, Nemateleotris magnifica (Pippin)
- Pink Spotted Watchman Goby, Cryptocentrus leptocephalus (Gollum)
- Tiger Shrimp, Penaeus sp.
- Hermit Crabs, Pagurus sp.
- Snails, probably Astrea sp.
- Yellow Polyps, Parazoanthus gracilis
- Clove Polyps, Clavularia sp.
- Colt Coral, Cladiella sp.
- Xenia Coral, Xenia sp.
Written by: Robert Lawrence, postdoctoral research scientist