A study has found a new link between inflammation and cell division -- two of the most important processes in the human body whose accurate control is a holy grail for scientists researching the prevention of infection, inflammatory disease and cancer."This is an exciting discovery: for the first time we find a link between the system which regulates how cells divide and the basis of some of medicine's most intractable diseases," said Mike White, who led the joint study by the University of Manchester and Liverpool. Inflammatory signals produced by a wound or during an infection can activate a protein called Nuclear Factor-kappaB (NF-kB), which controls the activity of genes that allow cells to adapt to the situation.Incorrect control of NF-kB is associated with inflammatory diseases, such as Crohn's disease, psoriasis and rheumatoid arthritis. It has also been linked with ageing and some cancers.
A key way in which human cells adapt to signals in their environment is by dividing to produce new cells through a repeating pattern of events, called the cell cycle. A cell first makes copies of its DNA, in a stage known as the DNA synthesis phase, and then divides into two daughter cells.The cell cycle is controlled by a family of proteins called E2 factors, which control the start of the new cell's DNA synthesis phase.The study published recently in the journal eLife showed that the NF-kB and E2 factors bind to each other in the cell. This controls the level of the NF--kB signal, which is enhanced just before DNA synthesis, but reduced during the DNA synthesis phase.Scientists also showed that signals which activate NF-kB can change the timing of cell division.The findings suggest that direct interactions between E2 factor proteins and NF-kB enable cells to decide whether to divide and determine how they react in different ways to inflammatory signals.