RNA modification defects can lead to high blood pressure

Genetic information is stored in DNA and is passed on in a very stable manner from one cell to the next or from one generation to the next. On a cellular level, genetic information is transcribed from DNA into RNA (ribonucleic acid) and then mostly "translated" into proteins, which carry out cellular functions. This normally involves modifying the RNA so that this information can be “read" correctly or used appropriately – in order to adapt to changes in prevailing conditions. Researchers from the Division of Cell and Developmental Biology at MedUni Vienna have now shown that defects in this RNA modification can result in altered smooth muscle contraction, cardiovascular diseases and high blood pressure. 

The main finding of the study by lead author Mamta Jain supervised by Franz-Michael Jantsch of MedUni Vienna's Division of Cell and Developmental Biology is: if a particular RNA modification in smooth muscle is defective or inadequate in the mouse model, there is a greater likelihood of high blood pressure and cardiovascular problems developing as a result of over-contraction. Working with MedUni Vienna's Division of Anatomy, this finding was further corroborated by post-mortem tests on bodies donated to science: defective RNA modification in the aortic muscles was observed in those who had died with a hypertrophic, or enlarged, heart: This vital modification was around 50% lower than in most people. Normally, RNA modification of 90% can be read in the proteins but, in the affected individuals, it was below 40%.

Figure:This illustration describes how ACC-BLA circuit controls innate freezing response depending on its activity level

When animals encounter danger, they usually respond to the situation in one of two ways: to freeze or to flee. How do they make this quick decision in a life or death moment? According to KAIST neuroscientists, there are two types of fear: learned versus innate. The latter is known to be induced without any prior experience and is thus naturally encoded in the brain. A research team under Professor Jin-Hee Han in the Department of Biological Sciences identified the brain circuit responsible for regulating the innate fear response.

The study, which appeared in the July 24 issue of Nature Communications represents a significant step toward understanding how the neural circuits in the prefrontal cortex create behavioral responses to external threats. This also represents a new paradigm in therapeutic development for fear-related mental disorders. Responses of freezing or fleeing when facing external threats reflect behavioral and physiological changes in an instinctive move to adapt to the new environment for survival.

Researchers from the Marine Megafauna Foundation, University of Southampton, and Sharkwatch Arabia have used a 'biological passport' to monitor the habits of the whale shark, Earth's largest fish

Whale sharks, the world’s largest fish, roam less than previously thought. Local and regional actions are vital for the conservation of this globally endangered species moving forward, according to a new study by researchers from the Marine Megafauna Foundation, University of Southampton, and Sharkwatch Arabia. Their findings are published today in the journal Marine Ecology Progress Series.

Previously, genetic research indicated that whale sharks mixed within distinct populations in the Indo-Pacific and Atlantic Ocean, respectively. This new study used stable isotope analysis, a biochemical technique, to demonstrate that whale sharks feeding at three disparate sites in the Western Indian Ocean (Mozambique and Tanzania) and the Arabian Gulf (Qatar) rarely swim more than a few hundred kilometers north or south from these areas.
 
“Whale sharks are amazing swimmers, often moving over 10000 km each year, and they can dive to around 2000 meters in depth. Biochemical studies tell us more about where they go and what they do when they’re out of our sight”, said Dr Clare Prebble, who led the research as part of her PhD project at the University of Southampton.
 
The researchers used isotopes of nitrogen and carbon that have similar chemical properties, but vary in their atomic mass. Ratios between the heavier and lighter isotopes of these elements vary naturally across different habitats in the marine environment. For example, more of the heavier isotopes are found in near-shore environments than offshore. These ratios stay consistent as they are passed up through the food web, from tiny marine plants to top predators, and therefore provide a record of the animal’s feeding and movement behaviors. Stable isotope analysis thereby provides a ‘biological passport’ for whale sharks.