MIC 102 Lecture Notes - Lecture 22: Endogenous Retrovirus, Viral Disease, Plasmid
Document Summary
Initial infection by varicella zoster herpes virus causes chickenpox. At a later point, lvirus reemerges from neuron where it has been hiding. In response to stress, immunological suppression, some sort of physiological change in host. Not all long lasting viruses are technically latent. Some seem to have positive effects: protection, similar viruses, even bacterial. Cancer: cell transformation, viral infection generates. Endogenous retrovirus: making viral genes work for us: cyncytins. Temperate, lysogenic, latent all describe the same idea. Balance between extremes of lytic and lysogenic activity. What is the decision point for switching from latency to lysis. Integrates only at the attb site circularize upon entry into cell using sticky ends, dna ligase joins them. Some phages can integrate at multiple sites these sites do not share homologous sequences. Viral encoded integrases are responsible for site specific recombination. Induction events negativity affecting host are often signals for the induction of lysis. Uv exposure can be such a signal.
