What type of enzymes are used during the first stage of Strand Displacement Amplification (SDA)?

The first stage of Strand Displacement Amplification (SDA) involves the use of restriction enzymes. These enzymes are crucial because they recognize specific DNA sequences and cleave the DNA at those sites. In SDA, a restriction enzyme is used to generate a 3' overhang that serves as a primer binding site for a DNA polymerase in the subsequent amplification steps. This mechanism facilitates the amplification of the target DNA in a way that allows for strand displacement, which is a defining characteristic of SDA.

It's important to understand that while ligases, reverse transcriptases, and DNA polymerases have their roles in molecular biology techniques, they do not initiate SDA. Ligases form bonds between DNA fragments, reverse transcriptases synthesize DNA from RNA templates, and DNA polymerases are primarily responsible for synthesizing new DNA strands. However, it is the restriction enzymes that actually initiate the process by cutting the DNA and enabling the formation of the necessary overhangs for amplification. Thus, the use of restriction enzymes is integral to the first stage of the SDA process.