Even the well renowned biologists have come to a unanimity that nothing could beat the ‘motherly instincts’ when it comes to threats on their progeny. Despite, how lyrical it might sound, at least the biologists at the University of Iowa have already gave their thumbs up this notion. A study conducted at the university discovered that female roundworms could alert their future offspring of dangers they might be vulnerable to, when born. Moreover, these mothers have the ‘super-power’ to hint on such alarms even before the offspring has been conceived.
The study shows that a mother roundworm releases a chemical called serotonin on sensing danger, (such as a change in temperature, for instance) which can be harmful or even fatal to the animal. The serotonin travels from the mother’s central nervous system to her unfertilized eggs, where the warning is stored, so to speak, in the egg cells and then passed to offspring after conception.
In experiments, the researchers discovered that embryos from mothers who passed along the serotonin danger signal had higher birth rate and survival success than female roundworms who had the serotonin signaling removed. “Our study shows the mother’s sensory response to danger actually protects the progeny,” says Veena Prahlad, associate professor in the Department of Biology and corresponding author of the study, published in the journal eLife. “Put more simply, she seems to be protecting her potential babies before she protects her own self.”
There are hints that this communication channel exists in mammals, but researchers know little about how it happens. So Prahlad and her team decided to study it in detail in roundworms. The researchers showed that the release of serotonin by maternal neurons triggers gene expression in the gonad that protects the immature egg, ensuring its survival after fertilization and even making roundworm larvae more resilient to stressors.
The team confirmed these findings by comparing birth and survival rates of roundworm larvae that received the serotonin signal to those from whom the serotonin signaling enzyme had been removed. The results showed roundworm larvae that received maternal serotonin had a 94% birth success and survival when exposed to higher temperatures compared to a 50% birth success and survival rate in higher temperatures for roundworm offspring with the serotonin signaling enzyme removed.
