- Briefly describe how each of the following mutations would affect gene expression and/or phenotype:
In a yeast haploid cell, a mutant occurs which creates a stop (nonsense) codon at the 12th amino acid in the gene responsible for excision repair
Response
Nonsense mutation normally causes a change in the gene which modifies the commands of creating proteins. Instead of replacing one amino acid for another, the alteration in one of the DNA base pair impulsively signals to the cells to discontinue the creation of the proteins (Peilin & Zhongming, 2017). These results in reduced proteins which can function inappropriately or fail to function at all leading to genetic based sicknesses (Peilin & Zhongming, 2017).
- Briefly describe how each of the following mutations would affect gene expression and/or phenotype
Reactive oxygen species have resulted in numerous G -> A transitions in various mitochondria- encoded tRNA genes
Response
Intracellular reactive oxygen species (ROS) synthesis is controlled by different hormones, cytokines and development aspects. When there is an upsurge in the ROS levels beyond a certain verge, this is unsafe for the existence of cells like lipid peroxidation and oxidative adjustment of proteins and nucleic acids (Zehuan Liao et al., 2017). At low concentrations, ROS act as subordinate messengers that are liable for upholding physiological roles like host defense, signal transduction and gene expression Zehuan Liao et al., 2017).
References
Peilin Jia, & Zhongming Zhao. (2017). Impacts of somatic mutations on gene expression: an
association perspective. Briefings in Bioinformatics, 18(3), 413–425. https://doi.org/10.1093/bib/bbw037
Zehuan Liao, Damien Chua, & Nguan Soon Tan. (2019). Reactive oxygen species: a volatile
driver of field cancerization and metastasis. Molecular Cancer, 18(1), 1–10. https://doi.org/10.1186/s12943-019-0961-y
