DNA Replication & Repair MCAT Practice Question
During homologous recombination repair of double-strand breaks, RAD51 protein coats single-stranded DNA after exonucleolytic resection, forming a nucleoprotein filament. This filament then searches for homologous DNA sequences. What is the primary function of this RAD51-DNA filament in the homologous recombination process?
Answer choices
- ADirect ligation of broken DNA ends without template guidance
- BRecruitment of mismatch repair proteins to the lesion site
- CNucleotide excision of all damaged DNA around the break
- DHomology search and DNA strand invasion to initiate recombinationCorrect answer
- EDegradation of the entire chromosome to prevent propagation of errors
- FProtection of single-stranded DNA from nuclease degradation while waiting for checkpoint completion
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