 Restriction
enzymes are used for several purposes. One of these is to cut and then
recombine pieces of DNA in particular orders. This is what is called "recombinant
DNA". A specific region of a gene that we wish to study can be cut
out and separated using the ability of restriction enzymes to cut at specific
sequence locations. The DNA fragment can be ligated next to a piece of
DNA from a "gene promoter" that acts as an on/off switch. The
promoter can be switched on and the gene fragment is expressed in a situation
where we can test its function alone. The DNA fragment can also be ligated
into a "vector", or carrier, that allows us to increase the
number of copies of the DNA so it may be more easily studied. |
