MCAT® ExamBiological and Biochemical Foundations of Living SystemsEasy
A research team is investigating a novel antiviral drug that targets viral replication by interfering with an enzyme responsible for synthesizing DNA from an RNA template. This enzyme is crucial for the life cycle of retroviruses. Which enzyme is the drug most likely targeting?
- ADNA polymerase
- BDNA ligase
- CReverse transcriptase
- DRNA polymerase
Show answer & explanationAnswer & explanation
Correct answer: C. Reverse transcriptase
Reverse transcriptase is an enzyme found in retroviruses that catalyzes the synthesis of DNA from an RNA template, a process known as reverse transcription. Interfering with this enzyme would effectively halt retroviral replication.
Why the other options are wrong
- A. DNA polymerase synthesizes DNA from a DNA template.
- B. DNA ligase joins DNA fragments together.
- D. RNA polymerase synthesizes RNA from a DNA template.
Reverse Transcriptase Function
An enzyme, primarily found in retroviruses, that catalyzes the synthesis of DNA from an RNA template, a process known as reverse transcription.
- Crucial for retroviral replication (e.g., HIV).
- Synthesizes a DNA strand using an RNA template.
- Also has RNase H activity to degrade the RNA template.
- Can then synthesize a second DNA strand using the first DNA strand as a template.
Memory trick: Reverse transcriptase: RNA to DNA, a viral trick.