ANIMAL VIRUSES Chapter 14, pp 341-370
A) Multiplication of animal viruses
1) attachment
2) penetration = nucleocapsid enters Fig 14-8, p 350
3) uncoating
4) replication of viral nucleic acid (variable)
retroviruses (cause cancer, AIDS)= RNA genome copied into DNA,
may integrate into host cell DNA = provirus, and remain latent
Mechanism of replication depends in part on the nature of the
viral genetic material i.e. double stranded DNA or RNA vs single
stranded DNA or RNA. If single stranded - is it “sense”
(+) or “anti-sense” (-)? (Fig 14-9. p351)
5) maturation
6) release (variable); budding = Fig 14-11, p353
B) Latent viral infections, see Table 14-7, p355 for examples
C) Effects of animal viruses of host cells
1) cytopathic effects (Fig 14-3, p346)
a) transformed cells
b) inclusion bodies e.g. Negri bodies characteristic of
rabiesvirus
c) formation of giant cells = polykaryocytes
2) cancer and oncogenes (Table 14-9, p 358 compares normal vs
cancer cells)
a) oncogenes = genes capable of causing cancer
D) Examples of certain animal viruses
1) tumor causing viruses Table 14-11, p360
2) Retrovirus
E) Unconventional agents of disease (scrapie, Creutzfeldt-Jakob
disease, Kuru)
1) prions