Question

There is a gene in eukaryotes under the control of a transcriptional activator that ultimately regulates chromatin structure. This transcription factor requires dimerization to function. Given your understanding of how transcription factors work, list four different mutations that could disrupt the regulation of this gene and the functional consequences of these individual mutations. Consider both cis- and trans- acting elements and different protein domains.

Answer 1

Answer:

Mutation that prevents Transcription Factors Dimerisation

Mutation that prevents Transcription Factors from binding to Chromatin Remodeling proteins.

Mutation that prevents Transcription Factors from binding DNA

Mutation that prevents binding of co- activator

Explanation:

Several different mutations can affect Transcription Activators to be  unable to promote transcription of its target gene:

1. Mutation that prevents Transcription Factors Dimerisation: In the given example, because the Transcription Factors requires dimerisation to function. A mutation that disrupts dimer formation will prevent the Transcription Factor from activating gene transcription.

2. Mutation that prevents Transcription Factors from binding to Chromatin Remodeling proteins: Since this transcription activator results in Chromatin remodeling, a mutation in the domain that binds to and recruits chromatin remodeling proteins will prevent the transcription factor from being able to promote chromatin remodeling.

3. Mutation that prevents Transcription Factors from binding DNA: A mutation that abrogates either the ability or the specificity of transcription Activator to bind to DNA will prevent the activator to effectively promote transcription of target gene.

4. Mutation that prevents binding of co- activator: Many activators promote transcription from a locus in the presence of a co-activator. A mutation that prevents the binding of the activator to the activator will prevent expression of the target gene.