Author Archives: Lisa Hildebrand

What ties the Panama Canal, squeaky swing sets, and the Smithsonian together? Birds of course!

Have you ever wondered why you see birds in some places and not in others? Or why you see a certain species in one place and not in a different one? Birds have wings enabling them to fly so surely we should see them everywhere and anywhere because their destination options are technically limitless. However, this isn’t actually the case. Different bird species are in fact limited to where they can and/or want to go and so the question of why do we see certain birds in certain areas is a real research question that Jenna Curtis has been trying to get to the bottom of for her PhD research.

  • Jenna conducting field birding surveys on Barro Colorado Island (BCI)
  • Jenna next to one of their (absurdly heavy) autonomous recording devices

Jenna is a 4th year PhD candidate working with Dr. Doug Robinson in the Department of Fisheries & Wildlife. Jenna studies bird communities to figure out which species occur within those communities, and where and why they occur there. To dial in on these big ecological questions, Jenna focuses on tropical birds along the Panama Canal (PC). PC is a unique area to study because there is a large man-made feature (the canal) mandating what the rest of the landscape looks and behaves like. Additionally, it’s short, only about 50 miles long, however, it is bookended by two very large cities, Panama City (which has a population over 1 million people) and Colón. Despite the indisputable presence and impact of humans in this area, PC is still flanked by wide swaths of pristine rainforest that occur between these two large cities as well as many other types of habitat.

Barro Colorado Island can be seen in the centre of the Panama Canal.

A portion of Jenna’s PhD research focuses on the bird communities found on an island in the PC called Barro Colorado Island (BCI), which is the island smack-dab in the middle of the canal. To put Jenna’s research into context, we need to dive a little deeper into the history of the PC. When it was constructed by the USA (1904-1914), huge areas of land were flooded. In this process, some hills on the landscape did not become completely submerged and so areas that used to be hilltops became islands in the canal. BCI is one such island and it is the biggest one of them in the PC. In the 1920s, the Smithsonian acquired administrative rights for BCI from the US government and started to manage the island as a research station. This long-term management of the island is what makes BCI so unique to study as we have studies dating back to 1923 from the island but it has also been managed by the Smithsonian since 1946 so that significant development of infrastructure and urbanization never occurred here.

Large cargo vessels pass next to BCI on their transit of the Panama Canal

Now back to Jenna. Over time, researchers on the island noticed that fewer bird species were occurring on the island. There are now less species on the island than would be expected based on the amount of available habitat. Therefore, Jenna’s first thesis chapter looks at which bird species went extinct on BCI after the construction of PC and why these losses occurred. She found that small, ground-dwelling, insectivore species were the group to disappear first. Jenna determined that this group was lost because BCI has started to “dry out”, ecologically speaking, since the construction of PC. This is because after the PC was built, the rainforest on BCI was subjected to more exposure from the sun and wind, and over time BCI’s rainforest has no longer been able to retain as much moisture as it used to. Therefore, many of the bird species that like shady, cool, wet areas weren’t able to persist once the rainforest started becoming more dry and consequently disappeared from BCI.

Another chapter of Jenna’s thesis considers on a broader scale what drives bird communities to be how they are along the entire PC, and what Jenna found was that urbanization is the number one factor that affects the structure and occurrence of bird communities there. The thing that makes Jenna’s research and findings even more impactful is that we have very little information on what happens to bird communities in tropical climates under urbanization pressure. This phenomenon is well-studied in temperate climates, however a gap exists in the tropics, which Jenna’s work is aiming to fill (or at least a portion of it). In temperate cities, urban forests tend to look the same and accommodate the same bird communities. For example, urban forest A in Corvallis will have pigeons, house sparrows, and starlings, and this community of birds will also be found in urban forest B, C, D, etc. Interestingly, Jenna’s research revealed that this trend was not the case in Panama. She found that bird communities within forest patches that were surrounded by urban areas were significantly different to one another. She believes that this finding is driven by the habitat that each area may provide to the birds. 

Jenna has loved birds her entire life. To prove to you just how much she loves birds, on her bike ride to the pre-interview with us, she stopped on the road to smash walnuts for crows to eat. Surprisingly though, Jenna didn’t start to follow her passion for birds as a career until her senior year of her undergraduate degree. The realization occurred while she was in London to study abroad for her interior design program at George Washington University in D.C. where on every walk to school in the morning she would excitedly be pointing out European bird species to her friends and classmates, while they all excitedly talked about interior design. It was seeing this passion among her peers for interior design that made her realize that interior design wasn’t the passion she should be pursuing (in fact, she realized it wasn’t a passion at all), but that birds were the thing that excited her the most. After completely changing her degree track, picking up an honor’s thesis project in collaboration with the Smithsonian National Zoo on Kori bustard’s behavior, an internship at the Klamath Bird Observatory after graduating, Jenna started her Master’s degree here at OSU with her current PhD advisor, Doug Robinson in 2012. Now in her final term of her PhD, Jenna hopes to go into non-profit work, something at the intersection of bird research and conservation, and public relations and citizen science. But until then, Jenna will be sitting in her office (which houses a large collection of bird memorabilia including a few taxidermized birds) and working towards tying all her research together into a thesis.

To hear more about Jenna’s research, tune in on Sunday, October 6th at 7 PM on KBVR 88.7 FM, live stream the show at http://www.orangemedianetwork.com/kbvr_fm/, or download our podcast on iTunes!

Proteins run the show (except when they unfold and cause cataracts)

Your eye lenses host one of the highest concentrated proteins in your entire body. The protein under investigation is called crystallin and the investigator is called Heather Forsythe.

Heather is a 4th year PhD candidate working with Dr. Elisar Barbar in the Department of Biochemistry and Biophysics. The Barbar lab conducts work in structural biology and biophysics. Specifically, they are trying to understand molecular processes that dictate protein networks involving disordered proteins and disordered protein regions. To do this work, the lab uses a technique called nuclear magnetic resonance (NMR). NMR is essentially the same technology as an MRI, the big difference being the scale at which these two technologies measure. MRIs are for big things (like a human body) whereas NMR instruments are for tiny things (like the bonds between amino acids which are the building blocks of proteins). Heather employed OSU’s NMR facility (which has an 800 megahertz magnet and is on the higher end of the NMR magnetic field strength range) to investigate what the eye lens protein crystallin has to do with cataracts.

  • Dr. Elisar Barbar (L) and Heather Forsythe (R) with an NMR sample tube.
  • Heather with an NMR sample tube.

Your eye completely forms before birth, and the lens of the eye that helps us see is made of a protein called crystallin. This protein is essential to the structure and function of the eye, but it cannot be regenerated by the body so whatever you have at birth is all you will ever have. However, in the eye lens of someone affected by cataracts, the crystallin proteins become unfolded and then aggregate together. They stack on top of each other in a way that they are not supposed to. A person with cataracts will suffer from blurry vision, almost like you’re looking through a frosty or fogged-up window. While the surgery to fix cataracts (which basically takes out the old lens and puts in a new, artificial one) is pretty straight-forward and not very invasive, it isn’t easily accessible or affordable to a lot of people all over the world. Cataracts is attributed to causing ~50% of blindness worldwide, likely due to the fact that not everyone is able to take advantage of the simple surgery to fix it. Therefore, understanding the molecular, atomic basis of how cataracts happens could result in more accessible treatments (say a type of eye drop) for it worldwide.

This is where Heather comes in. There are different types of crystallin proteins and Heather zeroed in on one of them – gamma-S. Gamma-S is one of the most highly conserved proteins (meaning it hasn’t changed much over a long time) among all mammals, which tells us that it’s super important for it to remain just the way it is. Gamma-S makes up the eye lens by stacking on top of itself, making a brick wall of sorts ensuring that the eye lens retains its structure. However, research prior to Heather’s found that with increased age there is an increase in a modification called deamidation, which occurs in the unstructured loops of the gamma-S protein. Deamidation is a pretty minor change and is common in proteins all over the body, however in the eye lens if too much of it happens it no longer is a minor issue since it starts to disrupt the structure and protein-protein interactions of the eye lens. Heather’s collaborators at Oregon Health Sciences University found that there are two sites on the gamma-S protein (sites 14 and 76) where these deamidation events increase the most in cataracts-stricken eyes. It’s been known for a while that this deamidation is associated with cataracts however we never knew why it is associated with cataract formation because the changes caused by this modification were seemingly minor. This is how the Barbar Lab, and Heather specifically, became connected to this work since they specialize in studying unstructured proteins and protein regions, such as the loops present in gamma-S.

An example of an “1H(x-axis) 15N(y-axis) HSQC” spectra, aka, the fingerprint of a protein. This spectra is of WT gamma-S crystallin.

These deamidation changes are mimicked in the lab by creating two different mutants of the gamma-S protein’s DNA. Heather then compared the two mutants with the normal DNA by putting them through a series of experiments using the trusty NMR. The NMR is basically a large magnet that can make use of the magnetic fields around an atom’s nucleus to determine protein structure and motions. When Heather puts a protein sample into the NMR, the spins of the atomic nuclei will either align with or against the magnetic field of the NMR’s magnet. The NMR spits out spectra, which look like a square with lots of polka dots. This is essentially the fingerprint of the protein, unique to each one and extremely replicable. Heather can analyze this protein fingerprint since the different polka dots represent different amino acids in the gamma-s protein. Heather can compare spectra of the two mutants to the spectra of the normal protein to see whether any of the dots have moved, which would signal a change in the position of the amino acids.

After running experiments which measure protein motions at various timescales, from days to picoseconds, Heather discovered significant changes in protein dynamics when either site 14 or 76 was deamidated, however at different timescales. What this discovery means is that if both of these mutations are associated with cataracts and they are changing the same regions of the gamma-S protein, then these regions are likely central to changes resulting in cataracts. Therefore, research could be directed to target these regions to perhaps come up with solution to prevent and/or solve cataracts in a non-surgical way. The results of Heather’s study were recently published in Biochemistry.

Heather with her dog Piper.

Heather is from Arkansas where she completed her high school and undergraduate education. Living in a single-parent, non-academic home at this time, it took Heather a long time to figure out how to navigate the scientific and college-application scene, as well as even coming to the realization that science was something she was good at and could pursue. Despite receiving scholarships for college, she still had to work multiple jobs while in high school and college to have enough money for car-payments and gas to get to extra-curricular activities and volunteer jobs in the science field; things critical for graduate school applications. As a result, Heather is a strong advocate for inclusivity, striving to make things like science and college in general more accessible to low-income and diverse students. Heather’s decision to leave Arkansas and come to the PNW was inspired by advice she received from her undergraduate advisor who told her “not to go anywhere where you wouldn’t want to live. You will learn to love research, whatever it ends up being, but if you live in an environment that you don’t find fulfilling, then you are going to suffocate.”. Following this advice has lead Heather to where she is now – the senior in her lab where she has become a mentor to undergraduates, makes Twitter-famous Tik Tok videos (see below), goes on adventures with her dog Piper, and publishes cutting edge structural biology research.

Heather and her undergraduate mentee performing The Git Up in the lab.

To learn more you can check out the Barbar Lab website and Twitter page.

To hear more about Heather’s research, tune in on Sunday, September 29th at 7 PM on KBVR 88.7 FM, live stream the show at http://www.orangemedianetwork.com/kbvr_fm/, or download our podcast on iTunes!