Jakub Harnoš
a biology graduate who now runs his own laboratory
An inspiring journey of a scientist seeking answers to the causes of developmental disorders.
Scientific careers often look carefully planned from the outside. But real life is usually much less straightforward. Jakub Harnoš is an Assistant Professor at the Faculty of Science, Masaryk University, and the head of the Harnoš Lab. But when he returned to Brno after less than two years as a postdoctoral researcher in New York, there was no clear plan. The COVID pandemic ended his stay abroad earlier than expected. He also returned without a finished publication, which is often very important for further academic career development.
Jakub Harnoš tells his personal and scientific story in the P-LAB CAST podcast, available on YouTube, Spotify, Podcasty.cz, and České podcasty. Below, you can read some of the most interesting parts of the story.
“When I came back from New York, I did not have a finished paper. In science, this is a problem because publications are, to some extent, the currency used to evaluate your work. But by chance, a position focused on frog research opened here at Masaryk University. I could use the experience I had gained abroad,” Jakub Harnoš remembers.
What now looks like a logical career step was actually the beginning of a completely new chapter. There was no established laboratory, no large team, and not even secure funding. There were only a few aquariums, grant applications, and a decision to try to build something new.
From a Speech Disorder to a Scientific Career
Harnoš openly talks about the fact that his journey was difficult from childhood. He had a serious speech disorder, which made normal communication difficult and naturally affected his self-confidence.
However, instead of stopping him, this experience became one of the reasons why he learned to keep going.
“When I was sixteen or seventeen, I could hardly speak. I spent much of my childhood listening to other people and observing the world around me. I had to work extremely hard on myself and almost reprogram my brain. If someone has a disability or another limitation, I would like to tell them one thing: do not let it stop you. Try to overcome it step by step and do not give up.”
This ability to keep going has stayed with him throughout his career. It helped him with learning languages, studying science, working abroad, and later building his own research team.
Interestingly, his interest in science did not start with a typical childhood fascination with nature. His high-school teachers and popular science discussions had a much stronger influence. As a teenager, he became interested in biology, chemistry, and the question of how life works at the cellular level.
The Frog That Changed Biology
Today, the Harnoš Lab studies early vertebrate development. But the main model organism used in the laboratory is still unfamiliar to many people.
Xenopus laevis, also known as the African clawed frog, is one of the most important model organisms in developmental biology. However, only a few laboratories in the Czech Republic work with it.
At first sight, it looks like an ordinary African frog. For scientists, however, it is very special. Its embryos develop outside the mother's body, are easy to manipulate, and allow researchers to follow development almost from the first minutes after fertilization.
“One major advantage of Xenopus is that we know exactly which part of the embryo we are working with and which structures will later develop from it. We can target the future eye, brain, spine, or specific parts of the nervous system. This allows us to study the effects of individual experiments very precisely,” Harnoš explains.
Interestingly, this frog was not always used only for research. In the 1930s, it was also used as a pregnancy test. Doctors discovered that when urine from a pregnant woman was injected into a female Xenopus, the frog started laying eggs. Before modern laboratory pregnancy tests became available, this was a surprisingly reliable diagnostic method.
How Do Cells Communicate?
The main research topic of the Harnoš Lab is communication between cells. In simple terms, the group studies how cells exchange information and how they coordinate their behaviour during development.
One major research direction focuses on neural tube closure. The brain and spinal cord later develop from the neural tube. The process takes only a few hours, but during this time hundreds of cells must perfectly coordinate their movement, shape, and communication.
“It is a fascinating process. Cells must know exactly where they should be, where they should move, and how they should change their shape. If something goes wrong in this communication, a serious developmental defect can develop,” Harnoš explains.
Neural tube defects are one of the main reasons why this research is important. They affect approximately one in two thousand newborns and can have very serious or fatal consequences.
Their occurrence has been significantly reduced, for example, by folic acid supplementation during pregnancy. However, scientists still do not understand all the molecular mechanisms that control neural tube development.
When Cell Signalling Meets Energy
Besides neural tube research, the Harnoš group is developing a second research direction that started directly in Brno.
It focuses on the well-known Wnt signalling pathway, one of the most important communication systems between cells.
During their experiments, the researchers noticed something unusual. Molecules that were expected to work mainly at the cell membrane also appeared inside mitochondria.
“At first, it did not make sense to us. Wnt signalling is known mainly for controlling communication between cells. But suddenly, we saw that some of its components were entering mitochondria. We started asking whether they could influence the production of energy needed for cell movement and cell rearrangements during embryonic development,” Harnoš explains.
If this hypothesis is confirmed, it could reveal an important connection between cell communication and energy metabolism.
In simple terms, it could explain the link between what a cell “knows” it has to do and the energy it needs to actually do it.
From Embryonic Development to Cancer
Although this is basic research, it may have many future applications.
The mechanisms that control cell movement during embryonic development are often also used by cancer cells.
“Metastatic cells use principles that are very similar to those used by developing tissues. If we understand how cells coordinate their movement during embryonic development, we may also better understand the processes behind cancer spread. This is one of the long-term reasons why this type of research is important,” Harnoš says.
This also shows why basic research matters. The path from a laboratory discovery to a practical medical application can be very long. But without understanding basic biological principles, it is impossible to develop new treatments.
People often imagine that a laboratory head spends most of the time doing experiments. In reality, the job is much more complicated.
“Suddenly, you realize that you are not only a scientist. You are also a psychologist, an economist, a team leader, someone who has to find funding, and someone who has to motivate other people. Moving from being an experimental scientist to leading your own group is a huge shock,” Harnoš admits.
More than twenty students have worked in his laboratory during the past five years. Most of them moved to the private sector or to other institutions after finishing their studies. According to Harnoš, this is one of the typical features of the Czech academic environment.
Despite all these challenges, he now considers building his own research team one of the biggest professional adventures of his life.
Life Outside the Laboratory
Perhaps surprisingly, science does not take all of his time.
Together with his partner, Harnoš founded a project called Brno Essentials, which helps foreign workers and students living in Brno.
They help with translations, communication with authorities, small household repairs, dog sitting, and Czech language lessons.
At first sight, this work has almost nothing to do with scientific research. But according to Harnoš, that is exactly why he enjoys it.
“I like combining completely different things. I think it gives you a broader perspective. If I do only one thing, I start living in a very narrow world. And I do not want that.”
Whether he talks about science, family, or helping other people, one thing seems to connect everything: curiosity and the willingness to look for new paths.
Meet
Jakub Harnoš
He is currently a researcher at the Department of Experimental Biology at the Faculty of Science, Masaryk University, where he also leads his own research group, the Harnoš Lab. His team studies the early embryonic development of the frog Xenopus laevis, whose embryos develop outside the mother’s body. This research could not only help answer questions about the origins of developmental disorders, but also potentially contribute to our understanding of the processes underlying the spread of cancer.
Career and professional path
In 2018, he successfully completed his PhD in Biology at the Department of Experimental Biology. He subsequently worked as a postdoctoral researcher at the Icahn School of Medicine at Mount Sinai in New York. He has also completed research stays at the University of Würzburg and Julius-Maximilians-Universität Würzburg in Germany.
He is the recipient of several prestigious awards and grants, including the MUNI Award in Science and Humanities Junior and the MUNI Junior Star. He is also a member of the Junior Faculty and has led the aforementioned Harnoš Lab since 2021.
Authors: Vojtěch Pres, Lucie Kuchtová, Adéla Lerchová