In: Biology
Ans:- Single Digest
For single digest of the plasmid containing GFP gene will give a linear band of 3700 bp. Because, GFP cloned into plasmid is 3700 bp and upon single digestion restriction enzyme will cut the plasmid at single site. If circular plasmid is cut once it will become linear and size of the plasmid remain the same.
Double Digestion
Since the size of GFP is 700 bp. If you double digest the plasmid with enzymes it will gives two linear bands one of 700 bp for GFP and other is 3000 bp the plasmid backbone. The logic is that the GFP is cloned using these two restriction site only into the plasmid, so if you digest plasmid with these two enzymes the GFP band of 700 bp will come out from plasmid and 3000 bp of linear backbone is also present.
Uncut plasmid
The uncut plasmid is the supercoiled plasmid purified from the mediprep. So, when uncut plasmid is run on the gel the actual size of plasmid is bite difficult to predict. So, the supercoiled plasmid will give you a band anything from 3000 bp to 3700 bp. As, supercoiled plasmid can move faster than linear plasmid.
GFP PCR
Since, the GFP is of 700 bp. Thus, the GFP PCR will produce a linear band of 700 bp.Since, primers will only amplify the size of the GFP.
The control PCR
The control PCR won't give any band of GFP because it doesn't contain GFP gene. So, no band will be seen in control PCR.
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