A team of scientists in the US have unearthed the beneficial effects of luminous bacterium called Vibrio fischeri on its host, which is the Hawaiian bobtail squid. According to them, these bacteria regulate the daily rhythm of their hosts through interaction with the clock genes. This new study has proved to be a major step in identifying the widespread effects of the microbial flora that inhabit innumerable plants and animals.
The study was conducted by Margaret McFall-Ngai and colleagues at the University of Wisconsin-Madison. They found out this unique way of setting the biological clock of the squid by the symbiotic bacterium. The new research is the first to show the influence of the microbial population on the regulation of circadian rhythm of the marine creature. It is a well-known fact that the various microbial agents inhabiting a living host constantly carry out an array of activities. This novel finding could be one of the several operations conducted by the bacterium.
For that matter, a varied range of bacteria, fungi and other microorganisms inhabiting the human gut are responsible for carrying out the various steps of digestion such as production of vitamins and vital amino acids, degradation of toxins, and preventing the foreign matter from entering the abdomen.
The biological clock of the humans is dependant on the environmental cues in the form of light and dark. It very much controls the patterns of sleep and wakefulness as well as few metabolic functions. The Hawaiian bobtail squid can successfully save itself from the predators by utilizing some self-defensive techniques like releasing ink or burying in the sand. However, the most important tool of the marine invertebrate is its colony of bioluminescent V. fischeri that carries a light organ to camouflage the body. This study discovered that the light generated from the bacterium gives rise to a genetic cascade in the cells of the light organ of the squid. It is quite likely that the cascade manages the daily cycle of activity in accordance to the various environmental cues. McFall- Ngai claims that the marine animal responds to the luminescence coming out from its own light organ rather than the environmental light.
The entire group of researchers considers the squid’s light organ to be a valuable model for assessing the interaction between the bacterium and its host. The discovery ushers the importance of circadian rhythms in playing a vital role in controlling the different biological functions.