Recombinant DNA: Cloning Genes with Simple Animations

DNA isolation begins with breaking open cells to release their genetic material.The cell membrane and nuclear envelope are broken down using chemical and physical methods.Restriction enzymes act like molecular scissors, recognizing specific DNA sequences.When they find their target sequence, they make precise cuts in both DNA strands.This process creates multiple DNA fragments with sticky ends that can later be joined to other DNA molecules.To isolate specific DNA fragments, we use gel electrophoresis.DNA fragments are loaded into wells at the top of a gel matrix.When an electric field is applied, DNA fragments migrate through the gel, with smaller pieces moving faster than larger ones.This creates a pattern of bands, with each band representing fragments of a specific size.Researchers can then identify and isolate their gene of interest based on its expected size.To prepare the vector for our gene of interest, we first identify specific restriction sites on the plasmid.Restriction enzymes recognize and cut at specific DNA sequences, creating sticky ends that will be compatible with our gene of interest.Our gene of interest has been prepared with matching sticky ends, allowing it to fit perfectly into the cut plasmid.DNA ligase then joins the gene to the plasmid by forming bonds between the sticky ends.The plasmid also contains an antibiotic resistance gene, which will help us select bacteria that successfully take up our recombinant DNA.Our recombinant plasmid is now complete, containing both our gene of interest and the antibiotic resistance marker.To insert our recombinant plasmid into bacteria, we use a process called transformation.The bacteria are subjected to heat shock - rapid temperature changes between forty-two and zero degrees Celsius.This process makes the bacterial membrane temporarily permeable, allowing the plasmid to enter.The bacteria are then grown on selective media - plates containing antibiotics.Only bacteria that have successfully taken up the plasmid, which contains an antibiotic resistance gene, will survive on the selective media.The transformed bacteria will multiply, forming visible colonies on the plate.Each transformed bacterium can now produce the protein encoded by our gene of interest.As the bacteria continue to divide, each new cell contains the plasmid and can produce our protein of interest.