In a region of the fruit fly genome with no genes 2 separate

In a region of the fruit fly genome with no genes, 2 separate base pair substitutions occur that lead to formation of a protein-coding gene “from scratch”.

a) What are the two most important features of the nucleotide sequence that need to be created by these base pair substitutions for this region to become a gene?

b) If the gene doesn’t perform a function that is beneficial to the organism, what do you predict would happen to this gene?

c) If the gene codes for a protein that has the same function as another gene in the genome, what do you predict could happen to this gene? Describe two predictions. Answer depends on how gene transcription is controlled.

Solution

The question is about the mutations in noncoding region of DNA becoming functional or to become active.

a. Two most important features of the nucleotide sequence that need to be created by these base pair substitutions for this region to become a gene are:

1. To have regulatory region

2. To have promotor region

then comes enhancer/operator elements.

b. If the gene does not have beneficial function for cell then there is one concept called gene silencing. This gene silencing at gene level.

c. If the that happens, then at the level gene transcription, two phenomena will take place:

1. Methylation of gene so the other gene with the same protein function will not produced

2. Histone modification: Acetyation and deacetylation by Histone Acetylases and Histone Deacetylase will make the other silent.