There is no specific drug or potential vaccine for dengue though about 40% of the world’ s population is at the risk of dengue virus infections. There is also a complete lack of understanding of the pathogenesis or the manner of development of the diseases and it has been one of the hurdles for developing antivirals for this virus infection.
A group of researchers from the University of Hyderabad (UoH) School of Life Sciences department of biochemistry led by Dr. M. Venkata Ramana and Prof. Naresh Babu Sepuri claim to have found the manner in which the virus attacks the host cells and this could lead to research into potential drugs to treat dengue.
The ~11 kb size gnome (RNA) genome of dengue virus has three structural and seven non-structural (NS) proteins along with two untranslated regions one each on both ends. Dengue protease or NS3 among them plays a pivotal role in virus multiplication and contributing to disease development. The non-structural protein-3 (NS3) enters the host mitochondria – a cell’s powerhouse converting energy from food into energy for biological processes, and cuts through a very important matrix protein or GrpEL1 which is essential for major functions of the mitochondria.
The UoH study states that this is the first ever report, for human and animal viruses, where it is shown how an important viral protein like NS3 enters the mitochondrial matrix. This was observed in severe dengue infected clinical samples obtained from Dr. V.S.V. Prasad, The Lotus Children’s Hospital, here.
It suggested that mitochondrial dysfunction might be one of the reasons for the decrease in the number of platelets that results in ‘thrombocytopenia,’ a condition in dengue patients. Dr. Ramana and Prof. Naresh have also identified that SARS COVID-2 virus-encoded NS-3 also have mitochondrial target sequence with potential to interfere with mitochondrial functions.
Hence, identification of the first mitochondrial matrix protein being targeted by a human virus, by UoH researchers in dengue virus infection, may also strengthen our fight against human viruses like COVID-19, it said and the study was published recently in Journal of Virology (https://jvi.asm.org/content/early/2020/06/18/JVI.01178-20).