Heat-Killed Bacteria Alters Zebrafish Body Clock Genes

Inside our bodies, there's something called the circadian clock. It's like a tiny timekeeper that controls our daily rhythms and interacts with our environment. When we talk about infection, it can change how these 'clock' genes work. In zebrafish, this is affected by light. Scientists wanted to see how dead bacteria influences these genes in zebrafish cells called Z3. They found that dead Streptococcus pneumoniae, also known as HK-Spn, boosted the activity of certain 'clock' genes.In the dark, HK-Spn made genes like cry1a, per3, and per1b more active. When there was light, HK-Spn quickly made per2 and cry1a work more. Interestingly, this effect was stronger with more light. A chemical called N-acetyl cysteine stopped HK-Spn from boosting these 'clock' genes, showing that light plays a crucial role.