Question

Name 3 ways of controlling gene expression.

Answer 1

1. First level of gene regulation in eukaryotes is transcription. The process is regulated in order to increase or decrease the level of expression of a gene. DNA elements called as enhancers bind to proteins called as activators to increase gene expression and DNA element called as silencer bind to proteins called as repressors to decrease gene expression. Promoter is a regulatory element to which RNA polymerase enzyme bind to initiate the transcription of downstream genes.

2. The second level of gene expression in eukaryotes is RNA processing. It during splicing, capping and tailing processes. It occurs in order to ensure that mature messenger RNA transcript has been properly formed from premature RNA formed after transcription. Any messenger RNA transcript which is found to be damaged is degraded rapidly.

3. Third Level of gene regulation expression in eukaryotes is the stable transport of messenger RNA from nucleus to the cytoplasm. It is important because it stabilizes the Messenger RNA being transported and protect it from exonucleases.

4. The fourth level of gene expression regulation is translation in which the sequence of amino acid is formed using messenger RNA as a template. The regulation is important for determining the correct base pairing between codon of messenger RNA and anticodon transfer RNA and addition of correct amino acid to the growing polypeptide chain.

5. 5th level of regulation of gene expression in eukaryotes is post translational modification. In this level, proteins are chemically modified and folded so that they can achieve their final three dimensional structure which is also called as the native state of proteins. With native state of proteins is very crucial to their function and therefore this level is regulated tightly. Any damaged protein or with folded protein is chemically modified by the addition of ubiquitin group to lysine of that protein and is targeted for degradation by 26s proteasome pathway.

Please rate high.