13: RNA reverse transcription

Temin predicted that DNA is _ in RNA tumor virus replication

an intermediate

primer (is / is not) required for reverse transcriptase

is

primer required for reverse transcriptase

tRNA molecule that virus captures from host

T or F. All RNA tumor viruses contain a reverse transcriptase.

true

All RNA _ viruses contain a reverse transcriptase.

tumor

reverse transcription occurs here (location)

cytoplasm

3 enzyme activities in reverse transcriptase

1. rna-dependent dna polymerase

2. rnase H activity

3. DNA dependent DNA polymerase

RNA-dependent DNA polymerase (has / does not have) proof reading

does not

RNA-dependent DNA polymerase had (high / low) mutation rate

high

what degrades RNA in the DNA:RNA hybrids

RNase H activity

_ makes a DNA duplex after RNase H activity destroys the viral genomic RNA

DNA-dependent DNA polymerase

outline retrovirus lifecycle

1. reverse transcription using tRNA → viral DNA

2. integration of DNA into host chromosome

3. transcription

4. transport tRNA out of nucleus

5. translation and proteolysis

6. assembly and packing

T or F, you can fight aids with inhibitors of HIV reverse transcriptase

true

how does RNA reverse transcriptase add telomeres (General)

telomerase in germ line cells adds buffered DNA region with repeated sequences

Buffer DNA is added on to the 5’-3’ strand by telomerase in _

germ line cells

describe telomerase process

1. telomerase has internal RNA template (AC) that binds to TG of 3’

2. telomerase adds T and G residues (translocation)

3. telomerase dissociates and RNA primase synthesizes at RNA primer

4. DNA polymerase fills gap, DNA ligase seals link

5. RNAse removes RNA primer

6. exposed TG (no primer) binds with telomere-binding proteins

7. telomere duplex DNA-binding proteins attach → T-loop

reverse transcriptase (does / does not) require primer

does

telomere synthesis is (rna/ dna) dependent and (rna/dna) polymerase

RNA, DNA

All RNA viruses excluding retroviruses encode a protein with _

RNA-dependent RNA polymerase activity (RNA replicase)

RNA replicases are in which of the following:

plants, protists, fungi, insects, mammals

plants, protists, fungi,

RNA replicases are specific for the RNA of _

their own virus

RNAs of the host cell (are / are not) replicated

are not

outline life cycle of covid (RNA-dependent RNA polymerase activity)

1. RNA polymerase translated from genomic RNA +

2. RNA polymerase transcribes - from +

3. RNA polymerase transcribes mRNA from -

4. virus assembly

RNA → + → - → mRNA

list polymerases that need template

1. RNA-dependent RNA polymerase

2. reverse transcriptase

3. telomerase (internal template)

4. RNA polymerase II