Gene Regulation Basics
This process allows cells to conserve energy by adjusting metabolic enzyme activity or gene regulation based on environmental factors.
What is metabolic control?
Eukaryotic gene expression can be regulated at this primary stage involving the initial production of RNA.
What is transcription?
This type of gene promotes normal cell growth and can become cancerous when excessively active.
What is a proto-oncogene?
Epigenetic changes can be inherited but do not alter this fundamental structure in DNA.
What is the nucleotide sequence?
These proteins assist RNA polymerase in initiating transcription in eukaryotic cells.
What are transcription factors?
In bacteria, this DNA segment acts as an “on-off switch” for gene expression.
What is the operator?
This process involves adding acetyl groups to histone tails, making chromatin structure more open to transcription.
What is histone acetylation?
This gene is known as the “guardian angel of the genome,” and mutations in it are linked to many cancers.
What is p53?
The addition of methyl groups to DNA, often silencing genes, is known as this.
What is DNA methylation?
Located far from the gene they regulate, these DNA sequences boost transcription rates when bound by activators.
What are enhancers?
This type of operon is generally turned off and requires an inducer to activate transcription.
What is an inducible operon?
Differential gene expression allows cells with identical genomes to specialize into different types. This is essential for this type of cellular process.
What is cell differentiation?
Mutations in this gene can lead to a hyperactive protein, promoting excessive cell division.
What is the ras gene?
This inheritance mechanism transmits traits via non-genetic alterations such as DNA methylation or histone modification.
What is epigenetic inheritance?
This mechanism allows for different proteins to be produced from the same gene by including or excluding certain RNA segments.
What is alternative RNA splicing?
This term describes enzymes that are typically synthesized only when specific substrates are present, such as in the lac operon.
What are inducible enzymes?
This type of RNA is often degraded shortly after synthesis in prokaryotes but may last much longer in eukaryotes.
What is mRNA?
A decrease in activity in these genes, which inhibit abnormal cell division, can contribute to cancer development.
What are tumor-suppressor genes?
This process of modifying chromatin structure to regulate transcription is reversible, unlike mutations in DNA.
What is chromatin remodeling?
Large complexes that degrade proteins, maintaining protein quality control, are called this.
What are proteasomes?
When glucose levels drop in E. coli, this molecule increases, binding to CAP to activate the lac operon.
What is cAMP?
The small noncoding RNA molecules that can block or degrade mRNA to control translation include these two types.
What are miRNAs and siRNAs?
This model describes how multiple genetic mutations accumulate, often leading to cancer, particularly in colorectal cancer.
What is the multistep model of cancer development?
In genomic imprinting, methylation silences one of these from either the maternal or paternal genome.
What is an allele?
In yeast, these RNAs help form heterochromatin and silence transcription at centromeres.
What are siRNAs?