9.1.3 Effects on cell Physiology

Virus infection to a cell changes many of the physiological events, including changes in cellular metabolism, alteration in the ATP synthetic pathways, and deviation in the ion channel system. Physiological condition of a viable cell has a great effect on the outcome of a virus infection because the host cell provides the cellular machinery, regulatory proteins, and source for the viral nucleic acid, and protein synthesis. Attachment of virion with the receptors present on cell membrane leads to a series of events that are associated with the changes in morphological, physiological and biochemical characteristics of the cell. The receptor present on the cell surface determines the host range as well as tissue tropism of a viral species. Influenza virus infects the cell after binding to the sialic acid receptor present on the cell membrane. Similarly HIV infects the T-cells upon binding to the chemokine receptors of the cell. Usually virus infection alters the intracellular ion concentration that affects the cell membrane permeability (For example picornaviruses).

Table 9.2 Proposed cell membrane receptors for some viruses

 

9.1.4 Effect on host chromosome

Virus infection to a cell directly or indirectly leads to the damage of the host cell chromosome that may be lethal to the cell. If the cell does not die, viral genome may persist within the cell causing instability of cellular genome and alteration in the expression of proteins.