Often, many DNA-binding proteins act on a single switch/many seperate switches, with a single switch/many separate switches per gene, and the regulatory sequences of these switches are often located near/far from promoters.

A single switch many seperate switches far from

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Regulation of gene expression in eukaryotes - Transcriptional regulation in eukaryotes: an overview

32 important questions on Regulation of gene expression in eukaryotes - Transcriptional regulation in eukaryotes: an overview

What determines much of the cell’s architecture, its enzymatic activities, its interactions with its environment, and many other physiological properties?

The constellation of expressed proteins

True or false: at any given time in a cell’s life history, all of the RNAs and proteins encoded in its genome are expressed.

False:
At any given time in a cell’s life history, only a fraction of the RNAs and proteins encoded in its genome are expressed.

Can, at different times, the profile of expressed gene products differ dramatically, both in regard to which proteins are expressed and at what levels?

Yes

If the final product is a protein, regulation could be achieved by controlling ... Or ...

The transcription of DNA into RNA
The translation of RNA into protein.

Does gene regulation take place at many levels, including at the mRNA (through alterations in splicing or the stability of the mRNA) and after translation (by modifications of proteins)?

Yes

The varied ways that eukaryotic genes can be regulated have been divided into two general categories that reflect when they act:

Transcriptional gene regulation
Post-transcriptional gene regulation.

What is the term for when RNA acts post-transcriptionally to repress gene expression?

Gene silencing

What are 3 RNA players that participate in silencing genes?

miRNA
ncRNA
siRNA

Most regulation characterized to date takes place at the level of gene transcription/post-transcription?

Gene transcription

The basic mechanism at work is that molecular signals from outside or inside the cell lead to the binding of ... to specific DNA sites outside of protein-encoding regions, and the binding of these proteins modulates the rate of transcription. These proteins may directly or indirectly assist ... in binding to its transcription initiation site—the promoter—or they may repress transcription by preventing the binding of .....

regulatory proteins, RNA polymerase, RNA polymerase

Name 1 similarity and 3 Differences between the logic of gene regulation in bacteria and eukaryotes.

Both use sequence-specific DNA-binding proteins to modulate the level of transcription
Eukaryotic genomes are bigger, therefore the regulation of eukaryotic genomes is more complex, therefore they need more types of regulatory proteins and more types of interactions with the adjacent regulatory regions in DNA
Eukaryotic DNA is packaged into nucleosomes, forming chromatin, whereas bacterial DNA lacks nucleosomes.
In general, the ground state of a bacterial gene is “on,” whereas the ground state in eukaryotes is “off.”

In bacteria, can RNA polymerase usually bind directly to a promoter when no other regulatory proteins are around to bind to the DNA?

Yes

In bacteria, transcription initiation is prevented or reduced if the binding of RNA polymerase is blocked, usually through the binding of a ...

repressor regulatory protein

Do bacteria have activator regulatory proteins?

Yes, Activator regulatory proteins increase the binding of RNA polymerase to promoters where a little help is needed.

In many cases, the binding of the transcriptional apparatus is possible/not possible because nucleosomes are positioned to block the promoter. Thus, chromatin structure usually has to be changed to activate eukaryotic transcription. Those changes generally depend on the binding of sequence-specific DNA-binding ....

Not possible, regulatory proteins

The structure of ... around activated or repressed genes within cells can be quite stable and inherited by daughter cells

chromatin

In bacteria, are all genes transcribed into RNA by the same RNA polymerase? How many RNA polymerases function in eukaryotes?

Yes, 3

RNA transcripts are extensively processed during transcription in prokaryotes/eukaryotes; the 5′ and 3′ ends are modified and introns are spliced out.

eukaryotes

Is RNA polymerase II is much larger and more complex than its bacterial counterpart?

Yes, one reason it is more complex is that RNA polymerase II must synthesize RNA and coordinate the special processing events unique to eukaryotes.

Patterns of eukaryotic gene expression can be extraordinarily complex. True or false: one gene may be transcribed only during one stage of development and another only in the presence of a viral infection.

True

We can divide the regulatory proteins into two sets based on the DNA regulatory sequences they bind. Which 2?

The large RNA polymerase II complex and the general transcription factors. To initiate transcription, these proteins interact with cis-acting regulatory DNA sequences called promoter-proximal elements near the promoter of a gene.
Transcription factors that bind to cisacting regulatory DNA sequences called enhancers. These regulatory sequences may be located a considerable distance from gene promoters.

Generally speaking, promoters and promoter-proximal elements are bound by transcription factors that affect the expression of a few/many genes. Enhancers are bound by transcription factors that control the regulation of smaller/bigger subsets of genes. Often, an enhancer will act in only one or a few/multiple cell types in a multicellular eukaryote.

Many, smaller, only one or a few

Does much of the strategy of eukaryotic transcriptional control hinge on how specific transcription factors control the access of general transcription factors and RNA polymerase II.

Yes

Does the binding of RNA polymerase II to the promoter produce efficient transcription by itself?

No, transcription requires the binding of general transcription factors to additional promoter-proximal elements that are commonly found within 100 bp of the transcription initiation site of many (but not all) genes.

Mutations in which sites can have a dramatic effect on transcription?

the promoter-proximal elements

To modulate transcription, regulatory proteins possess one or more of the following functional domains:

A domain that recognizes a DNA regulatory sequence (the protein’s DNAbinding site)
A domain that interacts with one or more proteins of the transcriptional apparatus (RNA polymerase or a protein associated with RNA polymerase)
A domain that interacts with proteins bound to nearby regulatory sequences on DNA such that they can act cooperatively to regulate transcription
A domain that influences chromatin condensation either directly or indirectly
A domain that acts as a sensor of physiological conditions within the cell

Why was the succesfull cloning of Dolly a great surprise for the scientific community?

Because gamete (sperm and egg cells) formation was known to include sex-specific modifications to the respective genomes that resulted in sex-specific patterns of gene expression.

In eukaryotes, are most genes found in operons?

The proteins and DNA sequences participating in eukaryotic gene regulation are less/more numerous than the proteins and DNA sequences in prokaryotes.

A single switch
many seperate switches
far from

A key additional difference between bacteria and eukaryotes is that the access to eukaryotic gene promoters is restricted by ....

Chromatin

Gene regulation in eukaryotes requires the activity of large protein complexes that promote or restrict access to ... by RNA polymerase.

Gene promotors

The question on the page originate from the summary of the following study material:

An Introduction to Genetic Analysis | 9781319114770 | Anthony J F Griffiths, et al

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