Studies genetic characteristics that determine the choices that stem cells make
‘Stem cells constantly make choices. Stem cells are undifferentiated cells from which—after division—various specialized cell types are formed. The choices that stem cells make prior to and during cell division are important for the formation of the required number of mature daughter cells, but also for the self-renewal of stem cells.
‘We work a lot with zebra fish embryos during the first five days of their existence. The research is aimed at stem cells in the brain at an early stage in development. The embryos are larvae from fish that we have genetically modified by adding a certain gene to the hereditary material. For example, a gene that ensures that the cell lights up green under certain light. This allows us to visualize the stem cells under the microscope during the development of the embryos. We can then quickly see in which parts of the brain the stem cells are located.
‘Our research is of a fundamental nature. We study the formation of cells; how many are formed, where, and when? Since this is fundamental research, it is possible to use a laboratory animal that is less closely related to humans. Still, I am often surprised at how great the similarities are between humans and fish. I think that there are more similarities than there are differences. In general though, if you are asking a basic question, it is very well possible to work with basic organisms. That is why some laboratories work with, for example, yeasts or bacteria.
‘When stem cells are in the news, it is often related to new developments in medicine or the renewal or replacement of defective tissues or organs. Or related to potential treatments for diseases such as dementia, which is also an interesting field. Much knowledge is the result of studies in developmental biology and, in the future, our fundamental studies will certainly be useful. However, as a researcher I always remain cautious. The likelihood that your work will lead to a medical application is very difficult to predict.
‘We always start the study with creating a new gene that, in the first instance, we test in a cell culture. That is sufficient to see whether it works. Only when that has been confirmed do we continue with the genetic modification. This is how we create the transgenic fish that will later lay eggs for the embryos that we are studying.
‘Since most of the DNA in a cell is made up of non-active parts, it is very likely that the new transgene will be inserted in these parts and will not result in harmful interference. However, if this is the case, we would be able to see this clearly when we look at the embryos under the microscope. Only when the first young fish grow well and look normal do we use them to breed with. Strict selection is an important tool for us to avoid discomfort for the transgenic animals later on.’