Summary of the science
Cellular programming and reprogramming means changing one type of cell into another. Imagine cells like little workers in our body, and they have special proteins called transcription factors that can make them switch jobs, by turning specific genes on and off. When a cell turns into another cell, some of the genes will be 'hidden' as they were not needed to perform the function of that cell. When the cell 'changes jobs', it might need to access these 'hidden' genes. Some transcription factors, called pioneer factors, can access these genes. They can "pave the way" for other transcription factors, by opening up closed or hidden parts of our DNA and making certain genes more accessible to them.
About the research
Ken Zaret and his colleagues study the mechanisms underlying cellular programming and reprogramming, with a focus on a subset of eukaryotic transcription factors that possess the remarkable ability to induce cell fate changes. These transcription factors, crucial for embryonic development, can activate genes that are developmentally silenced and located in "closed" chromatin regions covered by nucleosomes. Special transcription factors, called pioneer factors, are capable of engaging their target sites on nucleosomal DNA and thus activating genes that were originally 'hidden'.
About the illustration
We wanted to emphasise the idea that specific genes are turned on and off depending on the cell and its specialised function. To highlight the complexity of this, we decided to show different cells with different genetic combinations in a grid like structure. Some cells are coloured in a darker colour to indicate that they have been reprogrammed to another cell type.