Reverse Primer in PCR - The Key to Amplification Success

Understanding the Role of Reverse Primer in PCR

PCR (Polymerase Chain Reaction) is an essential molecular biology technique used to amplify a specific DNA sequence. During this process, the correct annealing of primers is crucial for the successful amplification of the target DNA region.

The reverse primer is designed to be complementary to the 5' to 3' sequence found on the opposing strand of DNA. This primer anneals to the DNA with its 3' end facing towards the center of the sequence to be amplified.

After the denaturation of DNA strands in PCR, the reaction mixture is cooled to allow the primers to hydrogen bond with their complementary sequences. The Taq polymerase then extends these primers, synthesizing new strands of DNA.

Unlike natural DNA replication, which copies the entire genome, PCR specifically targets regions using sequence-specific primers. The reverse primer's correct orientation ensures the accurate amplification of the target DNA region in PCR.

Therefore, understanding the critical role of the reverse primer in annealing to DNA with its 3' end towards the center of the sequence is fundamental for the successful amplification of the desired DNA segment in PCR.