Chrysanthi-Maria Moysidou, Ivan Ezquerra Romano and Ashwin Karthick Natarajan

Our latest Marie Curie Fellowship winners

Three Max Delbrück post-docs have won Marie Skłodowska-Curie Actions Postdoctoral Fellowships of €174,000 each. They will study how we perceive wetness, the structure of a mitochondrial protein, and integrate bioelectronics into neuromuscular organoids respectively.

It’s a warm summer day. The dew point is high. The air feels heavy on your skin. How is the sensation of wetness processed in the brain? It is a question that Dr. Ivan Ezquerra Romano, a neuroscientist and post-doc in the Neural Circuits and Behavior lab of Professor James Poulet, aims to answer with his new Marie Curie fellowship.

How we sense wetness

Ivan Ezquerra Romano

Humans have thermal receptors that sense temperature, and mechanical receptors that sense pressure or touch. But we do not have receptors that recognize the level of moisture on the skin, explains Ezquerra Romano. It appears that we combine signals from these receptors to communicate the sensation of wetness to the brain. However, “no one has looked into how the nervous system integrates these signals,” he says.

To study the interaction, Ezquerra Romano will use immunohistochemical and calcium imaging techniques to identify the regions of the brain activated by wetness in freely moving mice. In combination with studies of transgenic mice, he hopes to pin down the specific neural circuits that allow us to enjoy a refreshing swim in the pool,” he says.

The research may have implications for treating symptoms of phantom wetness, he adds. Some people with Multiple Sclerosis, for example, report feeling that a limb is dripping wet, or that they have wet themselves. It may also point the way to more immersive virtual reality by enabling people to feel the sensation of wetness, even though they are in a virtual world.

DNA origami to understand protein structure

Ashwin Karthick Natarajan

Understanding the structure of a protein can help researchers uncover its function. But some important proteins aren’t stable enough to study. Take the MICOS complex of proteins – major structural elements of mitochondria. “They are too floppy,” says Dr. Ashwin Karthick Natarajan, a post-doc in the Structural Biology of Membrane Associated-Processes lab of Professor Oliver Daumke. “We could not characterize them properly.” The solution? DNA origami.

For his doctoral thesis in Finland, Natarajan experimented with creating knots in single strands of DNA and RNA so he could bend them into two- or three-dimensional shapes, one millionth the size of a human hair.

With his grant, Natarajan plans to insert MICOS proteins into a ring structure made out of DNA, in order to stabilize the proteins. Using cryo-electron microscopy, he will then try to discern their structure and function.

Many assume that the MICOS protein complex acts like a barrier that allows certain molecules to diffuse across the mitochondrial cristae junctionnarrow openings that connect cristae membranes to the inner boundary membrane. However, because the protein is not stable, this has been difficult to study. To test the theory, he plans to insert his DNA origami structures carrying MICOS proteins into giant unilamellar vesicles – a model membrane system to study interactions between lipids and proteins. Using staining techniques, he will then try to determine whether the protein complex is indeed acting as a cellular gatekeeper by allowing metabolites to move in and out of the cristae.

Understanding the function of the MICOS protein complex can pave the way toward new treatments. Mitochondrial dysfunction and abnormalities are hallmarks several diseases including neurodegeneration, disorders of the heart muscle and diabetes, for example.

Integrating organoids with bioelectronics

Chrysanthi-Maria Moysidou

Over the past decade, organoids – miniature 3D tissues have paved the way for new models that more realistically mimic healthy and diseased tissues. Dr. Chrysanthi-Maria Moysidou, a postdoc in the Stem Cell Modeling of Development and Disease Lab of Dr. Mina Gouti, aims to take the development of neuromuscular organoids to the next level. With her Marie Curie grant, she aims to combine neuromuscular organoids with novel bioelectronic devices.

I am an engineer by training but I have always been fascinated by biology,” says Moysidou, who has a background in chemical engineering, biotechnology and bioelectronics. “I enjoy building tools to better study and model complex biological systems.” She met Gouti at a conference and found the idea of neuromuscular organoids “unique and exciting.” Soon after, she applied for a postdoctoral position in Gouti’s lab.

Moysidou’s Marie Curie project aims to interface neuromuscular organiods with conformable bioelectronics to develop a more sophisticated and realistic model of neuromuscular development. The integration of bioelectronics with organoid models could help researchers steer the development and function of the organoids in specific and desirable ways. Such advancements in the field will enable a deeper understanding of human biology and disease mechanisms. “It would be great if the tools we are currently developing could aid the discovery of effective therapies that reach the clinic,” she says.

Text: Gunjan Sinha


Further Information

Marie Skłodowska-Curie Actions Postdoctoral Fellowships