What is Cloning?
Cloning, in biological terms, generally refers to the process of creating genetically identical copies of an individual or organism through either the natural process of asexual reproduction or in the unnatural setting of a lab using tools capable of genetic modification. In biotechnology, these tools can be used to create cellular clones (cell cloning) or clones of biomolecules through a process called molecular cloning.
In molecular cloning, enzymes, plasmid constructs and competent cells are used to amplify, or in other words, create multiple copies of a DNA sequence. These DNA copies can be whole gene sequences, non-coding sequences, transcriptional sites or simply short DNA fragments.
The stages involved in a typical DNA cloning procedure are as follows:
- The first step involves the insertion of your isolated DNA sequence of interest into a circular piece of DNA known as a plasmid vector. DNA ligases and restriction enzymes enable this insertion to happen in a ‘cut and paste’ type process.
- Once the DNA fragment of interest has successfully ligated into the construct, this new recombinant plasmid is then transfected into a cellular host (competent cell) by either a number of different transformation processes.
- The transformed cells are then grown in specialized media to significantly increase their number. As these transformed cells reproduce they replicate the recombinant plasmid and pass it on to their daughter cells making copies or clones of the DNA that it contains.
If you are interested in purchasing the necessary tools required for DNA cloning have a look at the many products we have on offer in Molecular Cloning.
In order for a cell to accept a recombinant plasmid, it needs to be competent. Some bacteria possess intrinsic competence meaning they naturally contain the machinery necessary to bring extracellular DNA across their cell membrane. These include some strains of Bacillus subtilis, Escherichia Coli and various strains of yeast. When a cell host is not naturally competent artificial competence can be induced by introducing conditions that do not naturally occur in nature. Exposing cells to calcium chloride, heat shock and other stressful conditions can promote competence in many cases. Other common techniques include electroporation, sonication and viral transfection.
The type of cell used during the transformation process will depend heavily on a multitude of factors including whether the DNA is to be expressed as a protein, the type of plasmid vector used and the overall end application of the cloning experiment.
Here at ZAGENO you have the unique possibility to compare competent cells from different suppliers to find the most suitable one for your cloning experiment!