Dengue virus
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Dengue virus (DENV) is the cause of dengue fever. It is a mosquito-borne, single positive-stranded RNA virus of the family Flaviviridae; genus Flavivirus. Four serotypes of the virus have been found, and a reported fifth has yet to be confirmed, all of which can cause the full spectrum of disease. Nevertheless, scientists' understanding of dengue virus may be simplistic as, rather than distinct antigenic groups, a continuum appears to exist. This same study identified 47 strains of dengue virus. Additionally, coinfection with and lack of rapid tests for Zika virus and chikungunya complicate matters in real-world infections.
Cross section of a dengue virus showing structural components
Unfolded protein response
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The unfolded protein response (UPR) is a cellular stress response related to the endoplasmic reticulum (ER) stress. It has been found to be conserved between mammalian species, as well as yeast and worm organisms.
A simplified diagram of the initiation of the UPR by prolonged and overwhelming protein misfolding. Grp78 recruitment to chaperone the misfolded proteins results in Grp78 dissociation from its conformational binding state of the transmembrane receptor proteins PERK, IRE1 and ATF6. Dissociation results in receptor homodimerisation and oligomerisation to an active state. The activated cytosolic domain of PERK phosphorylates the eIF2alpha, inhibiting translation and resulting in cell cycle arrest. The activated cytosolic domain of IRE1 cleaves the 26bp intron from its substrate