Tools of Recombinant DNA Technology

Introducing the desired gene into the genome of a host organism is a challenging process. It involves insertion of the selected gene into the host which is facilitated by a vector which helps integration of the gene to form the recombinant DNA. This DNA is then introduced inside the host, sustained and carried forward.


Cloning Vectors

Cloning vector refers to a minute DNA molecule which self-replicates itself inside the host cell. Cloning vectors are utilized for duplicating the desired DNA fragment into the host cell. Features of a cloning vectors are:

  • They should be small in size.

  • They should be self-replicating inside the host cell.

  • They should have restriction site for action of the Restriction Endonuclease enzymes.

  • Insertion of benefactor DNA fragment should not hinder the replication of the vector.

  • They should possess some marker gene to identify the recombinant DNA.

  • They should have multiple cloning sites.


Recombinant DNA Technology

Recombinant DNA technology changes the phenotype of an organism (host) with the help of a genetically transformed vector. The cloning vector is then inserted into the genome of the organism. The process involves the insertion of a desirable foreign DNA with the gene of interest into the genome of the host. This gene is called recombinant gene and this method or technique is called recombinant DNA technology. A recombinant DNA technology can be carried out and accomplished with the support of some fundamental tools. The different tools used for the function are mentioned below:


Tools of Recombinant DNA technology

Restriction Enzymes:

  • These are enzymes which have restriction endonucleases that help in cutting, polymerases that aid in synthesis of DNA and ligases that facilitate binding.

  • The restriction endonucleases used in recombinant DNA technology have a vital role in outlining the location at which the desired gene of interest is introduced into the vector genome. 

  • These are of two types usually, named as endonucleases and exonucleases. The endonucleases cut within the strand of DNA whereas the exo nucleotides are involved in cutting the ends of the DNA.

  • The restriction endonucleases are specific to palindromic sequences and cut the DNA at specific points. There are 3 chief types of restriction endonuclease enzymes: Type-I Restriction Endonucleases, Type-II Restriction Endonucleases and Type-III Restriction Endonucleases.

  • They inspect the length of DNA and cut at the specific site known as the restriction site. This creates sticky ends in the sequence.

  •  The gene of interest and the vectors are cut by the same restriction enzymes to acquire the corresponding sticky ends, after which ligases help in binding the sticky ends.


Vectors

The integration of the gene of interest is done with the help of vectors. These are the vehicles that drive the gene inside the host organism. The most commonly used vectors are bacteriophages and plasmids for their high copy number.


Host Organism

The organism in which the recombinant DNA is introduced is called the host organism. It is the ultimate tool into which the vector drives the gene of interest using the enzymes.

Techniques like microinjection, gene gun, biolistic are employed to insert the recombinant DNA within the organism. This can be also carried out using alternate heating and cooling or use of calcium ions.

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Steps of Recombinant DNA Technology:

  1. Selection and seclusion of DNA to be inserted.

  2. Selection of an appropriate cloning vector.

  3. Insertion of DNA into vector to structure recombinant DNA molecule.

  4. recombinant DNA molecule is launched into a suitable host.

  5. Selection of altered host cells.

  6. Articulation and proliferation of DNA-inserted in the host.

FAQ (Frequently Asked Questions)

1. What are the Techniques of Recombinant DNA Technology?

Introducing the desired gene into the genome of a host organism is a challenging process. It involves insertion of the selected gene into the host which is facilitated by a vector which helps integration of the gene to form the recombinant DNA. This DNA is then introduced inside the host, sustained and carried forward. Steps of recombinant DNA technology:

  1. Selecting and isolating the DNA to be inserted.

  2. Selecting of a suitable cloning vector.

  3. Inserting the DNA into vector to structure recombinant DNA molecule.

  4. Recombinant DNA molecule insertion into a suitable host.

  5. Selection of altered host cells.

  6. Articulation and proliferation of DNA-inserted in the host.

2. What is the Principle of Recombinant DNA Technology?

Recombinant DNA technology changes the phenotype of an organism (host) with the help of a genetically transformed vector. The cloning vector is then inserted into the genome of the organism. The process involves the insertion of a desirable foreign DNA with the gene of interest into the genome of the host. This gene is called recombinant gene and this method or technique is called recombinant DNA technology. A recombinant DNA technology can be carried out and accomplished with the support of some fundamental tools. Introducing the desired gene into the genome of a host organism is a challenging process. It involves insertion of the selected gene into the host which is facilitated by a vector which helps integration of the gene to form the recombinant DNA. This DNA is then introduced inside the host, sustained and carried forward.