7 - Reverse Transcription Flashcards
virus genome not observed
virus genome is observed in all types EXCEPT circular, double-stranded RNA
retrovirus
a virus that inserts its RNA genome that is used to create complementary DNA
polymerase
DNA polymerase that can create DNA or RNA template
nuclease
enzymes that cleaves RNA only if it’s in an ENA/DNA complex
reverse transcriptase
DNA polymerase that makes a DNA from viral RNA, destroy the RNA, then use the newly synthesized DNA to make double-helical DNA
HIV inhibitors
- entry inhibitors
- nukes and non-nukes
- integrase inhibitors
- protease inhibitors
entry inhibitors
- blocks HIV from entering the cell
- attachment inhibitors
- CCR5 inhibitors
nukes and non-nukes (NRTIs or NNRTIs)
- inhibits HIV from changing ss RNA to ds DNA
- nucleoside reverse transcriptase inhibitors (NRTIs)
- non-nucleoside reverse transcriptase inhibitors (NNRTIs)
integrase inihibitors (INIs)
inhibits HIV from being integrated into DNA
protease inhibitors (PIs)
inhibits newly synthesized HIV from forming long molecules that can be infectious
anti-viral drugs
tricks polymerase into adding a blocker to inhibit DNA synthesis
HIV reverse transcriptase inhibitors
- NRTIs (nukes) that contains no 3’OH, therefore DNA synthesis will be terminated
- stops reverse transcriptase BUT will not stop DNA polymerase
prodrugs
- drugs that must be metabolized (in most cases, phosphorylated) to work as a drug
- triphosphorylated inhibitors will act as competitive inhibitors that terminated DNA extension
Rous sarcoma virus (RSV)
- virus that’s similar to ALV (evolved from) but causes cancer by blocking contact inhibition
- has one more gene, src, that causes sarcoma to develop
Avian Leukosis virus (ALV)
does not cause tumor formation
contact inhibition
cells stop growing when they touch each other
src gene
an oncogene that causes sarcoma
oncogene
transforms normal cell into a cancer cell
RSV evolution from ALV
accidental incorporation of adjacent c-src gene in chicken
telomerase
performs reverse transcription by extending telomeres through repeated DNA synthesis (uses RNA template to extend DNA)
RNA-dependent RNA polymerase
- not reverse transcription
- RNA makes more RNA (not DNA), therefore RNA is read directly
remdesivir
- more effective inhibitor for RNA-dependent RNA polymerase
- a prodrug modified to triphosphate that will position 3’OH in the wrong way, successfully inhibiting DNA synthesis
