The Filoviridae Family Corresponds To The Order Of Mononegavirales.
1801 WordsMay 11, 20178 Pages
The filoviridae family corresponds to the order of Mononegavirales. This growing family of pathogens are filamentous, enveloped viruses with a genome that is negative-stranded RNA (1
& 2). This family is known to be one of the most pathogenic viruses affecting humans and is mostly found in bats (their main reservoirs) (3 & 4). It is believed that these viruses are transmitted from person to person through body fluids or through objects that have been previously contaminated with body fluids (5). After transmission and incubation period (three to
21 days), the initial symptoms are headache, fever, vomiting and diarrhea. After, the virus may cause viraemia, coagulopathy, haermoorhagic fever and liver/ multi-organ failure; which in many cases…show more content…
The envelopes of EBOV and MARV are composed of glycoproteins (GP). GP are essential for the entry of the viruses into the host cell by attaching to its cell surface (10). GP is a homotrimer of GP1 (membrane protein) - GP2 (transmembrane protein) heterodimer linked by disulfide bonds (11 & 12). The mechanism on how GP1 and GP2 drive the introduction of the virus into the host cell is not well understood yet (7). However, it is known that is characterized by three steps: attachment, uptake, and membrane fusion (7). GP1 is involved in adhesion of the receptor with the host cell surface, whereas GP2 is involved in the virus-host cell membrane fusion and entry (13). In most cases GP1 is believed to bind to different glycosaminoglycans
(GAG) from the host cell i.e. heparin sulfate, to be able to efficiently enter the host cell (2).
GAGs are negative, unbranched polysaccharides found in mostly all cells surfaces but differ in composition between species (4). It is believed that GAGs are not the only possible way of attachment for filoviruses to the host surface, meaning that there are other host factors that aid in viral entry (2). After attachment, virions get into the host cell through micropinocytosis followed by endosome trafficking which leads to membrane fusion (7). A low pH due to the endosomal events is what leads to the initiation of membrane fusion (7).
G protein-coupled receptors (GPCR) are the biggest and most diverse family of protein in