Retrovirus + Herpesvirus

Viral Protein Localization (retro)

1. Secreted of TM proteins made on rough ER and secreted into ER lumen/left in ER

2. Rough ER buds off into golgi → golgi buds off into rough vesicles that fuse with cell membrane

3. assembly of enveloped viruses tales place at PM

Common Exponential Viral DNA Replication Mechanisms

1. Templated Directed

2. Each strand copied beginning to end

3. uses DNA dep. DNA pol.

Generation of dNTP for DNA synth only in S phase

Semi-discontinuous DNA Synthesis

• Bidirectional origin

• Synth of leading strand starts from ori on RNA primer

• Lagging strand in short pieces as template becomes open → Okazaki fragments

Primase

enzyme that initiates RNA synthesis

Rolling Circle Mechanism

1. Nick one strand

2. replicate by continuous copying (from 3’ OH end)

3. discontinuous DNA synth

4. further continuous and discontinuous synth

5. complete lagging strand

6. double stranded DNA template result

7. make more copies by going around again

Direct Repeat Ends

1. help package one genome

2. proteins bind to specific end sequence → empty capsid bind to these proteins

3. DNA stuffed in to package until end proteins hang out

4. cleavage

Nucleus FCN

sequesters DNA templates and enzymes into discrete replication sites in nucleus

• products of one replication cycle become templates for the next cycle

Proofreading

• Host DNA pol. proofread during DNA synth

  • Viral DNA pol. might not

Acyclovir

converted to a product that competitively inhibits HSV DNA pol.

Herpes Simplex-1 Repro Cycle

1. first proteins synthesized are transcriptional activators of genes

2. transcripts make proteins needed later in synth

3. late proteins are required for capsid assembly and membrane proteins

Latent Herpes Infection

• occurs primarily in neurons

• transcripts produced from parts of the genome to produce proteins required to maintain latency