Describe the Four Ways That Transposition Is Controlled.
Uncontrolled transposition is deleterious to the cell and thus, the frequency of transposition is generally kept to a minimum by various regulatory mechanisms. Describe the FOUR ways that transposition is controlled.
Transposition is the movement of a particular fragment of DNA from one part of a genome to another. A transposon is a segment of DNA which is capable of moving from a specific location on a DNA molecule to another location on the same or different molecule. For this reason, it is known as a “jumping element”. The recombination that takes place involves two unrelated sequences. This is unlike other homologous recombination events such as crossovers in meiosis and in transposition; there is a completely new arrangement of genes along the chromosome. A transposon could contain antibiotic resistance genes so that when it inserts itself into its target, it could confer resistance to the host. Transposons have therefore aided the development of plasmids which give multiple drug resistance to certain bacteria. Transposition can be both beneficial and hazardous to the host. Over time, transposons have led to genetic variability and evolution. This is due to their ability to generate mutations by insertion within a host’s genome. However, their insertion can lead to alterations in DNA arrangement such as cause deletions, inversions and chromosome fusions. For this reason, transposition can be deleterious. It is important to understand how the activity of transposable elements is regulated. Transposition activity must be limited so that there is little capacity to damage host DNA but still maintain advantageous features. For this to be achieved, a balance must be struck between too much transposition occurring and too little. This is known as the frequency of transposition. This essay will review the different types of regulatory mechanisms employed.
A transposon element consists of three major regions. It contains a gene for transposase, insertion
Transposition is the movement of a particular fragment of DNA from one part of a genome to another. A transposon is a segment of DNA which is capable of moving from a specific location on a DNA molecule to another location on the same or different molecule. For this reason, it is known as a “jumping element”. The recombination that takes place involves two unrelated sequences. This is unlike other homologous recombination events such as crossovers in meiosis and in transposition; there is a completely new arrangement of genes along the chromosome. A transposon could contain antibiotic resistance genes so that when it inserts itself into its target, it could confer resistance to the host. Transposons have therefore aided the development of plasmids which give multiple drug resistance to certain bacteria. Transposition can be both beneficial and hazardous to the host. Over time, transposons have led to genetic variability and evolution. This is due to their ability to generate mutations by insertion within a host’s genome. However, their insertion can lead to alterations in DNA arrangement such as cause deletions, inversions and chromosome fusions. For this reason, transposition can be deleterious. It is important to understand how the activity of transposable elements is regulated. Transposition activity must be limited so that there is little capacity to damage host DNA but still maintain advantageous features. For this to be achieved, a balance must be struck between too much transposition occurring and too little. This is known as the frequency of transposition. This essay will review the different types of regulatory mechanisms employed.
A transposon element consists of three major regions. It contains a gene for transposase, insertion
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