Nearly all cells in the body contain the same DNA sequences and the same genes. However, the genes are activated at different times in different cells, which requires that they be turned on or off at the right time. This means that cells need to be able to govern gene activity at the right level, which can be more or less crucial to their condition and survival. However, from the moment a gene is turned on or off, it takes some time before the genetic information is translated to a functional protein, making this governance complicated.
“It’s a bit like finding the right temperature in the shower. First you turn on too much hot water because it feels cold, and then it gets too hot, so you lower the temperature too much, since it takes time for the change to be noticed,” says Johan Elf, a researcher at the Department of Cell and Molecular Biology.
What’s more, the activity and governing of genes occurs partly at random, which previously made it difficult to analyze the consequences of time delays. With the new theory it is possible to study how the combination of time delays and randomness interacts in biochemical reactions, making possible a better understanding of why the regulatory system of cells looks the way it does and how it can go wrong when it fails.
The practical applications of the discovery will be a more detailed understanding of gene regulation, which in the long term may yield a better understanding of diseases that are caused by problems in the control function of cells.
The study was performed at the Uppsala University Center for Interdisciplinary Mathematics, and the researchers represent three different academic disciplines: applied mathematics (Andreas Grönlund), IT (Per Lötstedt), and cell and molecular biology (Johan Elf).