Regulaton of Gene Expression

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Gene regulation is the process of promoting or suppressing the expression of genes. Regulation can occur anywhere during transcription or translation. Sometimes, gene regulation also happens even before transcription. This is called epigenetic modification.

Epigenetic modifications occurs when compounds attach to DNA genes and alters gene expression. A good example of this is methylation. Methylation happens when methyl attaches to histones. This do not alter the DNA sequence. However, this gets the the DNA tightly wound around the histones. Transcription factors cannot bind to the DNA and the genes, therefore, cannot be expressed. Histone acetylation is another form of Epigenetic modifcation. This results in loosed packing of nucleosomes making it accessible for the transcription factors to bind enabling gene expression.

Expression of genes regulated during transcription or translation results to either suppression or promotion of RNA or protein synthesis. A 

Certain signaling pathways can lead to either decrease or increase of protein production in a cell. The growth factor signaling pathway activates, for example, the protein c-Myc and the translation regulator MNK1. 

c-Myc increases transcription of genes that promotes cell growth and division. This protein can lead to production of cancer cells when it is too active. Active MNK1 increases the rate of mRNA translation. Many key genes regulating cell division and survival  have mRNAs that form hairpin structures. With the presence of active MNK1, these genes are expressed at high levels driving cell growth and division.






References:
[1]https://www.healio.com/hematology-oncology/learn-genomics/genomics-primer/regulation-of-gene-expression-in-eukaryotes
[2]https://courses.lumenlearning.com/suny-wmopen-biology1/chapter/eukaryotic-gene-regulation/
[3]https://www.khanacademy.org/science/biology/cell-signaling/mechanisms-of-cell-signaling/a/introduction-to-cell-signaling

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