Question

16) W.O.F is a non-cellular infectious entity:
(Entry Test-2017)
a) Mycoplasma
c) Herpes virus
b) Escherichia coli
d) Diplococcus​

Answer 1

Answer:The family Herpesviridae is a large, diverse family of double-stranded enveloped DNA viruses. B virus (BV) (or macacine herpesvirus 1, herpesvirus simiae, monkey B virus, or cercopithecine herpesvirus 1) and cercopithecine herpesvirus 2 (CeHV-2) (or simian agent 8) are primate herpesviruses belonging to the alphaherpesvirus subfamily and as such are closely related to herpes simplex virus 1 (HSV-1). The HSV-1 entry process and virus-induced cell fusion require glycoproteins B (gB), D (gD), H (gH), and L (gL). Binding of gD to a cellular entry receptor is required for triggering membrane fusion. To date, four gD receptors, herpesvirus entry mediator (HVEM) (38), nectin-1 (6, 16, 36, 37, 48), nectin-2 (31, 62), and modified heparan sulfate (49, 50), have been identified. More recently, three gB receptors, the paired immunoglobulin-like type 2 receptor alpha (PILRα) (46), myelin-associated glycoprotein (MAG) (2), and nonmuscle myosin heavy chain IIA (NMHC-IIA) (2), have been identified. HVEM is a member of the tumor necrosis factor receptor family (61). Nectin-1 and nectin-2 are cell adhesion molecules that belong to the immunoglobulin superfamily and are widely expressed by a variety of cell types, including epithelial cells and neurons (53). Modified heparan sulfate generated by particular 3-O-sulfotransferases can also serve as a gD-binding entry receptor (50). PILRα was identified as an entry receptor that binds to gB (46). PILRα is expressed on cells of the immune system, including monocytes, dendritic cells, NK cells, B cells, macrophages, neutrophils, eosinophils, mast cells, and megakaryocytes/platelets and neurons (15, 28, 39, 40, 46, 47, 57). MAG is a cell surface molecule that is preferentially expressed in neural tissues, especially on myelin sheath, and plays an important role in the regulation of axonal growth (3, 30, 35, 60). NMHC-IIA is expressed in a wide variety of cultured cell lines and in various tissues and cell types in vivo (17, 58).

Explanation: