Exam 2 Chapter 15

You are studying a bidirectional enhancer with the sequence 5'-CCTA-3'. Regulatory transcription factors that bind this sequence should also bind ______. Multiple choice question. 3'-TAGG-5' 5'-GGAT-3' 3'-ATCC-5'

3'-ATCC-5'

What kind of protein is expected to enhance the ability of TFIID to initiate transcription? Multiple choice question. Repressor proteins Mediator Activator proteins

Activator proteins

The binding of a regulatory transcription factor to a(n) ........ can stimulate transcription 10- to 1000-fold, which is called ....... regulation.

Blank 1: enhancer Blank 2: up

A domain called an α- ....... is often found in transcription factors because it is the proper width to fit into the ....... groove of the DNA double helix.

Blank 1: helix Blank 2: major

In helix .......- .......-helix and helix- .......-helix motifs, an α-helix recognizes a base sequence in the major groove of the DNA.

Blank 1: turn Blank 2: loop

A regulatory transcription factor that enhances the rate of transcription is called a(n) ......

activator

A regulatory element that functions in the forward or reverse direction is said to be .......

bidirectional

DNA sequences that are analogous to the operator sites found near bacterial promoters are called ....... elements or ....... sequences.

control regulatory

Transcription factors that affect the ability of RNA polymerase to begin the transcription process may work by ______.

controlling the switch from the initiation to the elongation stage of transcription regulating the binding of the transcriptional complex to the core promoter

Transcription factor proteins contain regions called ...... that have specific functions

domain

Regulatory elements that inhibit transcription are called silencers and their effect on transcription is called ______ regulation.

down

You are studying a transcription factor that binds to DNA near a gene of interest. You discover that once the transcription factor binds, transcription of your gene of interest becomes undetectable. This is an example of ______. Multiple choice question. down regulation an activator a mediator up regulation

down regulation

Activators bind to ______. Multiple choice question. enhancers silencers RNA repressors

enhancers

The dimerization of two identical proteins results in a .......

homodimer

A domain that has a very similar structure in many different proteins is called a(n) ........

motif

The α-helix is often found in transcription factors because it is the ______.

proper width to bind into the major groove of the DNA double helix

The phenomenon where the level of gene expression is controlled so that genes can be expressed at high or low levels is called gene. .......

regulation

Regulatory transcription factors that prevent transcription from occurring are called ......

repressor

Regulatory transcription factors that prevent transcription from occurring are called .......

repressor

A ....... ....... is a protein that influences the ability of RNA polymerase to transcribe a given gene.

transcription factor

An enhancer is a DNA element that can be bound to a regulatory transcription factor, which leads to ______. Multiple choice question. DNA replication down regulation up regulation transcriptional repression

up regulation

What is a motif?

A domain that has a very similar structure in many different proteins

In helix-turn-helix and helix-loop-helix motifs ....... ....... side chains of the α-helix form ....... bonds with nucleotide bases.

Blank 1: amino Blank 2: acid or acids Blank 3: hydrogen or H

Repressors bind to ______. Multiple choice question. silencers activators enhancers

silencers

Gene regulation means that ______.

gene expression can be controlled so that genes can be expressed at high or low levels

The dimerization of two different proteins leads to a .......

heterodimer

DNA sequences in eukaryotes that can be bound by regulatory transcription factors, which then affect the ability of RNA polymerase to transcribe a particular gene are called ______. Multiple select question. regulatory elements core promoters operator sequences control elements regulatory sequences

regulatory elements control elements regulatory sequences

True or false: A transcription factor can have multiple domains. True false question.TrueFalse

True

An enhancer is a DNA element that can be bound to a regulatory transcription factor, which leads to ______. Multiple choice question. DNA replication up regulation down regulation transcriptional repression

up regulation