Methods for Introducing Cloning Vectors into Host Cells
Methods for Introducing Cloning Vectors
The next step is to introduce the cloning vector containing your target gene into a host cell. As the host cell multiplies, it creates a cell clone carrying that specific gene. The method used depends primarily on the cell type.
Transformation and Transduction in Bacteria
In prokaryotes like bacteria, DNA introduction occurs through the following processes:
Transformation
This occurs naturally in certain bacteria and can be achieved artificially by subjecting cells to physical treatments, such as heat or electric shock, and specific chemicals. The cell captures DNA molecules from the external environment, internalizes them, and incorporates them into its genome.
Transduction
This method involves introducing DNA into the host cell using a virus as a cloning vector to deliver the viral genome.
The Genetic Engineering Process
The recombinant DNA molecule replicates within the host cell. As the cell divides, progeny cells inherit the recombinant DNA, creating a population of identical cells—a clone containing the desired DNA. These segments can then be recovered, purified, and analyzed.
The process of genetic engineering follows these steps:
- 1st: The DNA containing the desired gene is cut with a specific restriction enzyme.
- 2nd: The vector DNA is cut with the same restriction enzymes so that the ends are complementary.
- 3rd: The desired DNA fragment is ligated to the vector.
- 4th: The resulting molecule is recombinant DNA.
- 5th: This recombinant DNA is introduced into a host cell.
- 6th: The host cell, typically a bacterium, divides repeatedly to produce a population of identical cells containing the desired gene.
- 7th: The desired gene is recovered from the host cells, purified, and analyzed.
Through this process, scientists have successfully introduced the gene for insulin production into bacteria. These cells divide rapidly, allowing for the mass production of pure insulin, which is then used to treat diabetics.