The concept of gene regulation is broadly similar between prokaryotes and eukaryotes, but the biochemical details differ tremendously.(a) Name the DNA regulatory elements that are most responsible for the developmental control of eukaryotic gene expression.(b) Name the DNA regulatory elements that are most responsible for the control of gene expression due to variable conditions (e.g. environmental stresses, hormonal signals, nutritional state).(c) What are the proteins that interact with these regulatory elements?(d) Describe two ways that 1) cell-specific, 2) developmental or 3) environmental regulation of gene expression is achieved. (You may choose to answer the question in a generic sense or by specifically referring to one of the three specific contexts, e.g. just developmental regulation of gene expression.)
Question
The concept of gene regulation is broadly similar between prokaryotes and eukaryotes, but the biochemical details differ tremendously.(a) Name the DNA regulatory elements that are most responsible for the developmental control of eukaryotic gene expression.(b) Name the DNA regulatory elements that are most responsible for the control of gene expression due to variable conditions (e.g. environmental stresses, hormonal signals, nutritional state).(c) What are the proteins that interact with these regulatory elements?(d) Describe two ways that 1) cell-specific, 2) developmental or 3) environmental regulation of gene expression is achieved. (You may choose to answer the question in a generic sense or by specifically referring to one of the three specific contexts, e.g. just developmental regulation of gene expression.)
Solution
(a) The DNA regulatory elements that are most responsible for the developmental control of eukaryotic gene expression are enhancers and promoters. Enhancers are sequences of DNA that can bind transcription factors to increase the likelihood of transcription. Promoters are sequences of DNA where RNA polymerase binds to start transcription.
(b) The DNA regulatory elements that are most responsible for the control of gene expression due to variable conditions (e.g. environmental stresses, hormonal signals, nutritional state) are response elements. These are specific sequences within the promoter region that can be recognized and bound by specific transcription factors in response to certain conditions.
(c) The proteins that interact with these regulatory elements are mainly transcription factors. Transcription factors are proteins that control the rate of transcription of genetic information from DNA to messenger RNA, by binding to specific DNA sequences.
(d) Two ways that gene expression is regulated include:
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Cell-specific regulation: This is achieved through the use of specific transcription factors that are only present in certain cell types. These transcription factors will only bind to the promoters of genes that are needed in that specific cell type, leading to the transcription and translation of those genes.
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Developmental regulation: This is achieved through the use of different transcription factors at different stages of development. For example, certain transcription factors may be present during embryonic development that trigger the expression of genes needed for the formation of certain tissues or organs. Once development is complete, these transcription factors are no longer produced, and the genes they control are no longer expressed.
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Environmental regulation: This is achieved through the use of inducible genes, which are only transcribed in response to specific environmental signals. For example, in bacteria, the lac operon is only transcribed in the presence of lactose. This allows the cell to conserve resources by only producing the enzymes needed to metabolize lactose when lactose is actually present.
Similar Questions
Which of the following is NOT a form of gene regulation in eukaryotes?Group of answer choicesCovalent modifications of DNA that keep the base pairing the sameChanges to the DNA sequence that change the introns that are includedBinding of proteins to the enhancers or silences to change the amount of mRNA producedA small RNA binding to the mRNA from the gene and causing it to be degraded.
Briefly describe the different levels of gene regulation (DNA modification, transcription, RNA processing and transport, translation, post-translational events).
Gene transcription is controlled by which of these elements?
DNA-binding proteins that regulate gene expression recognize what? Specific mRNA sequences Specific DNA sequences also called cis-regulatory sequences or elements Specific carbohydrate sequences Proteins in the nuclear pore Cytoplasmic domains of specific proteins
Read the following and answer any four questions: Gene regulation is the mechanism of switching off and switching on of the genes depending upon the requirement of cells and the state of development. Gene regulation is of two types: negative and positive. In negative gene regulation, the genes continue expressing their effect till their activity is suppressed. Positive gene regulation is the one in which the genes remain non - expressed unless and until they are induced to do it. Operon model is a co - ordinated group of genes such as structural gene, operator gene, promoter gene, regulator gene which function together and regulate a metabolic pathway as a unit, e.g., lac operon, trp operon, ara operon, etc. 1. Regulation of gene expression occurs at the level of: a. transcription b. processing/splicing c. translation d. all of these An inducible operon system usually occurs in A pathway. Nutrient molecules serve as B to stimulate the production of the enzymes necessary for their breakdown. Genes for inducible operon are usually switched C and the repressor is synthesised in an D form. 2. An mRNA molecule transcribed from the lac operon contains nucleotide sequences complementary to a. structural genes coding for the enzymes b. the operator region c. the promotor region d. the repressor gene. 3. Which statement correctly describes the control of transcription of the genes involved in the breakdown of lactose in Escherichia coli? a. A repressor protein binds to the operator and the genes are switched on. b. A repressor protein binds to the operator and the genes are switched off. c. A transcription factor binds to the promoter and the genes are switched on. d. A transcription factor binds to the promoter and the genes are switched off. 4. Function of catabolic activator protein in lac operon is: a. to form mRNA b. help to bind RNA polymerase c. code for repressor d. to activates lac gene when glucose is absent 5. In eukaryotes, the regulation could be exerted at a. transcriptional level (formation of primary transcript) b. processing level (regulation of splicing) c. transport of mRNA from nucleus to the cytoplasm all of these
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