What is your research interest?

I am interested in how cells achieve inner communication. Our cells are about 50 to 100 micrometers in size, but they are packed with many organelles. Yet cells achieve a tightly controlled communication inside. I am very interested in how the endoplasmic reticulum (ER) and the nucleus interact and communicate.

 

Why is correct communication between the ER and Nucleus important?

The ER is the factory of our cells. Most of our lipids and membrane proteins are produced in the ER. The nucleus contains our genetic material. It is separated from the rest of the cell by a boundary, called the nuclear envelope. When the cell grows, the nucleus also grows, and the new lipids and membrane proteins need to be provided from the ER to the nucleus. The connections between the ER and the nucleus are thus very important. If there is no connection, lipids and membrane proteins cannot be provided and the nucleus cannot grow and function properly. We are interested in how these connections are made and maintained and how those connections control the transport between the ER and the nucleus.

 

What is special about the microscopy approach you developed as a Postdoc?

Researchers usually use light microscopy to observe living cells and to monitor how cells divide and how cells grow. But in light microscopy there is a limit in spatial resolution. You cannot see how the inner organelles interact with each other. For that you need electron microscopy to see such tiny subjects at nanometer resolution. But electron microscopy has to be done under vacuum condition, which means you cannot see living cells. This was a dilemma. To overcome this dilemma, researchers including me established a microscopy method by which you can observe the same cell by both light and electron microscopy. By that you can study how ER and nucleus interact during key cellular processes such as nuclear growth.

 

What are the most important findings in your field in the last ten years?

Microscopy technologies have been greatly advanced in the last ten years. One of the Nobel Prizes in 2014 was for the development of the super-resolution fluorescence microscopy. Another Nobel Prize in 2017 was for the development of cryo-electron microscopy. Now it has become possible to combine different modalities of microscopy to achieve both high spatial and temporal resolution. Now we can study inner cellular events both at the right moment also at the molecular level. Many new discoveries have been made greatly advancing our understanding of cellular systems and disease pathogenesis which is crucial to understand for future advances in human health.

 

What fascinates you about science?

One of the best things for me in science is that I can always get inspiration and new ideas by interacting with creative scientists in the world, which is really stimulating and always gives me motivation.

 

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