How Genes Direct The Production Of Proteins- Exam III

Question 1

Cell achieve their specialized function based upon the expression of ______ and any subsequent _____ of the resulting proteins.

Answer 1

Specific genes; post-translational modifications

Question 2

What is degraded quicker DNA or RNA? Why?

Answer 2

RNA because of nucleophilic attack of the ribose moiety

Question 3

What degrades RNA very quickly?

Answer 3

Ribonuclease

Question 4

In both prokaryotes and eukaryotes, you can have adjacent genes that get transcribed in:

Answer 4

Opposite directions

Question 5

A segment of DNA that is transcribed into RNA and its associated transcriptional control regions

Answer 5

Gene

Question 6

The transcriptional control regions of genes and RNA

Answer 6

Promotor regions

Question 7

The type of RNA that is translated into proteins

Answer 7

Messenger RNA (mRNA)

Question 8

The type of RNA that are important for the transfer of amino acids to the growing peptide chain.

Answer 8

Transfer RNA (tRNA)

Question 9

What is the most abundant form of RNA?

Answer 9

Ribosomal RNA (rRNA)

Question 10

Form of RNA that encodes ribosomal proteins

Answer 10

Ribosomal RNA (rRNA)

Question 11

What form of RNA blocks the translation on specific mRNAs and thereby regulate gene expression?

Answer 11

microRNA (miRNA)

Question 12

What form of RNA turns off gene expression by directing the selective degradation of mRNAs

Answer 12

Small interfering RNAs (siRNAs)

Question 13

What form of RNA that process and chemically modify rRNAs

Answer 13

Small nucleolar RNAs (snoRNAs)

Question 14

What form of RNAs modify snoRNAs and snRNAs?

Answer 14

Small cajal RNAs (scaRNAs)

Question 15

Involved in telomere synthesis, X-chromosome interaction, and protein transport into the ER

Answer 15

Other non coding RNAs

Question 16

Abundance of rRNA in the cell

Answer 16

~80%

Question 17

abundance of tRNA in the cell:

Answer 17

~15%

Question 18

Abundance of mRNA inside the cell:

Answer 18

3-5%

Question 19

All RNAs have to be transcribed from a:

Answer 19

Gene in the genome

Question 20

In eukaryotic organisms, most protein coding genes are transcribed by:

Answer 20

RNA polymerase II

Question 21

When you see RNA polymerase II think:

Answer 21

Protein coding

Question 22

Transcription always starts at a _____ point in the DNA and requires unwinding of the DNA to create the proper single-stranded template

Answer 22

Specific

Question 23

Gene expression is regulated by numerous transcription factors that interact with ______ in DNA or proteins bound to these regions.

Answer 23

Promotor elements

Question 24

The presence/absence of specific factors is an obligatory first step in the initiation of ______ binding.

Answer 24

RNA polymerase

Question 25

An important sequence of the 5’ side (start site) of transcription

Answer 25

TATA Box

Question 26

Transcription starts at what base:

Answer 26

Base 1

Question 27

TATA box is rich in:

Answer 27

Thymidine and adenine residues

Question 28

The TATA box will bind a very important transcription factor, (a dimer) called:

Answer 28

TBP & TFIID

Question 29

The dimer that TATA box binds to is composed of:

Answer 29

TBP & TFIID

Question 30

The TATA box localizes the dimer to position itself relative to the start site of transcription through the binding of the _____ to the TATA box

Answer 30

TBP

Question 31

Once the TATA Box bind TBP what happens:

Answer 31

TFIID will bind and correctly position itself

Question 32

Once the TBP and TFIID factors are positioned properly, _____ will come in and position itself.

Answer 32

TFIIB

Question 33

The binding and positioning of TFIIB leads to the recruitment of:

Answer 33

A bunch of other factors

Question 34

Once the TATA box has bound TBP and TBP allows for the correct positioning of TFIID, and TFIID allows for the correct positioning of TFIIB, and TFIIB recruits all the other important guys, this will allow for the:

Answer 34

Proper binding of RNA polymerase II

Question 35

It’s important that RNA polymerase II positions itself:

Answer 35

Around the DNA molecule in the proper place

Question 36

The RNA polymerase II should be bound on the DNA so that the start site of transcription occurs at:

Answer 36

Nucleotide 1

Question 37

The TATA is located:

Answer 37

Left of the start site of transcription (-15 to -25 ) 5’ to the start site

Question 38

Once the RNA polymerase II has bound there is a ____ that wraps around the DNA

Answer 38

CTD- (cytoplasmic tail domain)

Question 39

A couple of _____ reactions occur on the cytoplasmic tail domain of the RNA polymerase II

Answer 39

Phosphorylation

Question 40

The phosphorylation reactions on the CTD of the RNA polymerase II leads to:

Answer 40

The disassembly of a lot of the general transcription factors

Question 41

When we have disassembly of most of the general transcription factors, caused by phosphorylation reactions on CTD, this allows for ____ activity and a _____ that is ready to go.

Answer 41

Helicase activity, and RNA polymerase ready to go

Question 42

Inside the binding pocket or the RNA polymerase, what is functioning?

Answer 42

Helicase

Question 43

The RNA polymerase is adding ______ to the growing RNA transcript through the uptake channel.

Answer 43

Ribonucleoside triphosphates

Question 44

On the growing mRNA transcript, the 5’ _____ is connecting to the 3’ ____

Answer 44

5’ Phosphate to 3’ hydroxyl

Question 45

RNA is not just a ____ molecule because it can fold back on itself and base pair

Answer 45

Linear molecule

Question 46

Key transcription factor TFIID is made of:

Answer 46

TBP subunit + TAF subunit

Question 47

The TBP subunit recognizes:

Answer 47

TATA box

Question 48

the TAF subunit recognizes other ____ sequences near the transcription start point and regulates DNA-binding by_____.

Answer 48

DNA sequences; by TBP

Question 49

TFIIB recognizes the _____ element in promoters

Answer 49

BRE

Question 50

The TFIIB accurately positions:

Answer 50

RNA polymerase II

Question 51

What element is important for accurately positioning the RNA polymerase at the transcriptional start site

Answer 51

BRE element

Question 52

All of the RNA polymerases have a preference for the types of genes that they bind- RNA Polymerase I: RNA Polymerase II: RNA Polymerase III:

Answer 52

RNA polymerase I- rRNA genes RNA polymerase II- protein coding genes, snoRNA genes, miRNA genes, siRNAgenes and most snRNA genes RNA polymerase III- tRNA genes

Question 53

Processing events of mRNA include:

Answer 53

Capping, Splicing, Editing, Polyadenylation, Transport

Question 54

Capping:

Answer 54

Guanasine cap added to 5’ end

Question 55

In protein coding genes, poly-A tail added to the 3’ end

Answer 55

Polyadenylation

Question 56

Transport of mRNA involves the movement out of the _____ and into the _____.

Answer 56

Nucleus ——> cytoplasm

Question 57

Linear coding sequence is made of all of the _____ joined

Answer 57

Exons

Question 58

In mRNA processing the 5’ and 3’ untranslated region gets:

Answer 58

Kept in the linear sequence

Question 59

splicing occurs by a complex of RNA and protein molecules collectively known as the

Answer 59

Splicesome

Question 60

The spliceosome is made up of:

Answer 60

SnRNAs in a complex with 7 protein subunits

Question 61

The spliceosome made of the snRNAs in a complex with the 7 protein subunits come together and form a:

Answer 61

SNP

Question 62

What are the snRNAs involve din splicing?

Answer 62

U1, U2, U4, U5 and U6

Question 63

The snRNAs of the spliceosome provide proper:

Answer 63

Base pairing with the mRNA

Question 64

Splicing will join the ___ end of exon 1 to the ____ end of exon 2 and the ____ end of exon 2 to the ______ end of exon 3

Answer 64

3’ end of exon 1 to 5’ end of exon 2 and the 3’ end of exon 2 to the 5’ end of exon 3

Question 65

Splicing involves the formation of a ____ structure.

Answer 65

Lariat

Question 66

In splicing, a particular ____ residue in the intron sequence that undergoes a nucleophilic attack at the junction between the intron and the exon.

Answer 66

Adenosine

Question 67

What is more important for splicing, the sequence of nucleotides in the exon or intron? Why?

Answer 67

The sequences in the intron because this determines where the splicing will occur

Question 68

We estimate about _____ proteins in the human proteome

Answer 68

~250,000

Question 69

The tropomyosin gene can be spliced to form what types of mRNA based on the splicing resulting in different isoforms of the mRNA

Answer 69

Striated muscle mRNA smooth muscle mRNA Fibroblast mRNA (x2) Brain mRNA

Question 70

The 5’ cap and splicing of the primary mRNA transcript occur as soon as the ______ emerges from the RNA polymerase

Answer 70

HnRNA

Question 71

The poly A tail added to the 3’ end occurs by a set of RNA-binding proteins and processing enzymes after it _____ from the RNA polymerase

Answer 71

Completely emerges

Question 72

The mature mRNA means that the mRNA has been:

Answer 72

Spliced, capped and poly tail added

Question 73

The mature mRNA gets transported from the nucleus to the _____ and to the ____ where protein synthesis can take place.

Answer 73

Cytoplasm and to the ER

Question 74

Small non coding RNAs that are about 21-25 nucleotides long

Answer 74

MicroRNA (miRNA)

Question 75

What type of RNA binds to the 3’UTR region of target mRNA to form an RNA-inducing silencing complex (RISC)

Answer 75

MiRNA

Question 76

MiRNA bind to the 3’UTR of mRNA to form an:

Answer 76

RNA-inducing silencing complex (RISC)

Question 77

The RISC (RNA-inducing silencing complex) formed by the miRNA :

Answer 77

Suppresses protein synthesis and or induces mRNA degredation

Question 78

What suppresses protein synthesis or mRNA degradation?

Answer 78

RNA-inducing silencing complex (RISC)

Question 79

Each miRNA can target ______ different mRNAs

Answer 79

Many

Question 80

MicroRNA genes are transcribed by:

Answer 80

RNA polymerase II

Question 81

These miRNAs are formed by: A miRNA gene gets transcribed through RNA polymerase II and they make an initial transcript that makes a hairpin double stranded molecule which is exported out of the nucleus and into the cytoplasm where a specific enzyme called ____ clips the bubble formed to create a mature miRNA that then binds to a bunch of proteins that make up a complex that up a ____ complex, and this complex binds to the mRNA at the 3’ untranslated region to form the ______.

Answer 81

Dicer; argonaute complex; RISC

Question 82

3 bases code for:

Answer 82

A single amino acid

Question 83

3 base sequence is known as a _____ in the mRNA

Answer 83

Codon

Question 84

The genetic code is _____ for all organisms

Answer 84

Universal

Question 85

Important features of the genetic code: (4)

Answer 85

1. Commaless 2. Degenerate 3. 3rd base less specific 4. 3 stop codons that do not code for amino acids

Question 86

The commaless feature of the genetic code means that the code is read from beginning to end so the _____ is critical.

Answer 86

Reading frame

Question 87

The degeneracy of the genetic code means:

Answer 87

More than one codon can make the same amino acid

Question 88

The third base rule of the genetic code means:

Answer 88

The 3rd base is less specific than the first 2 (wobble position)

Question 89

The 3 base genetic code allows for ____ possible codons.

Answer 89

64

Question 90

AUG codes for:

Answer 90

Methionine

Question 91

What are the 3 stop codons:

Answer 91

UAA UAG UGA

Question 92

Roberts Syndrome severity can be as simple as ______ or as harsh as ______.

Answer 92

Craniofacial abnormality to lethal embryology

Question 93

Roberts syndrome is a _____ mutation of ______

Answer 93

Homozygous mutation of ESCO2

Question 94

ESCO2 in Roberts syndrome encodes for an:

Answer 94

Acetyltransferase

Question 95

The ESCO2 in Roberts syndrome encodes acetyltransferase which is important for the formation of _____ that binds to chromosomes and creates cohesion between sister chromatids.

Answer 95

Cohesion complex

Question 96

The changes in the level of ESCO2 result in changes in the level of :

Answer 96

Ribosomal gene transcription.