Regulation Of Gene Expression I

Front 1

What is cDNA? How is it made?

Back 1

1. Complementary DNA library

2. Made using reverse transcriptase and DNA polymerase I

Front 2

What serves as the primer in the formation of cDNA?

Back 2

1. Isolated mRNA

Front 3

What enzyme nicks the RNA, thus forming the primer for DNA polymerase I?

Back 3

1. RNase H

Front 4

What is the role of T4 poly in cRNA?

Back 4

1. Makes the DNA blunt-ended

Front 5

What is the use of an oligodexoynucleotide probe?

Back 5

1. Used to isolate a gene for a particular protein with an unknown nucleotide sequence

2. Made complementary to one of the strands of the cloned DNA gene

Front 6

What factor should influence your choice of oligonucleotide to use?

Back 6

1. Peptide that contains amino acids that have the least number of degenerate codons

Front 7

How is immunoscreening done?

Back 7

1. Antibodies to the protein of the cloned DNA can be produced

2. Proteins of the colonies are transferred to a filter

3. Proteins are exposed to the antigen/ab complex to be detected

Front 8

What is the advantage of PCR?

Back 8

1. Gain a lot of information from a little genetic material

2. High amplification

Front 9

What is RAPD?

Back 9

1. PCR technique

2. Produces a fingerprint of an organism

3. Allows identification of disease-causing organisms

Front 10

From where is the DNA polymerase enzyme in PCR isolated?

Back 10

1. Thermophilic bacteria--- able to resist denaturation

Front 11

What are the steps of the PCR reaction?

Back 11

1. dsDNA is denatured

2. Primers are annealed to the DNA by cooling the mixture

3. DNA polymerase synthesizes new strands of DNA

4. Mixed is denatured again, yielding four DNA templates

5. DNA polymerase synthesizes new strands

6. Process is repeated=amplification

Front 12

What are constitutive proteins?

Back 12

1. Proteins found in relatively constant amounts in cells

Front 13

What are inducible proteins?

Back 13

1. Found in low concentrations in a given cell type

2. Concentrations can be increased due to proper stimulus

Front 14

Do eukaryotic or prokaryotic cells contain more DNA?

Back 14

1. Eukaryotic

Front 15

What is gene amplification?

Back 15

1. Replication of a gene responsible for forming a certain protein is greatly increased

Front 16

What is the example of gene amplification that Cox gave?

Back 16

1. During oogenesis of a fruit fly, chorion (eggshell) is amplified

Front 17

How do cancer cells develop resistance to methotrexate?

Back 17

1. Increasing number of genes for DHFR to 40-400 copies per cell

2. Extra copies form double minute chromosomes

Front 18

What are transposons?

Back 18

1. Jumping genes

2. Short in length

3. Can lead to abx resistance

Front 19

What enzyme is in charge of transposition?

Back 19

1. Transposase

Front 20

What are enhancers?

Back 20

1. cis acting DNA sequences

2. Activate transcription in the chromosome where they reside

3. Affect transcription of any gene in their vicinity

Front 21

What are the general eukaryotic gene promoters?

Back 21

1. TATA

2. CAAT

Front 22

How do enhancers work?

Back 22

1. Transcriptional activators bind to enhancers

2. Enhancers stimulate RNA polymerase to transcribe specific genes

Front 23

What are HREs?

Back 23

1. Steroid hormones bind receptors to enter the nucleus

2. Contains domains for DNA binding, one for the ligand, and one for activating of transcription

Front 24

What does the SV40 enhancer experiment show?

Back 24

1. Permissive enhancers can stimulate any promoter in the vicinity

Front 25

What does the metallothionein enhancer experiment show?

Back 25

1. Certain enhancers are not specific for a given promoter

Front 26

What does the pancreatic B-cell tissue enhancer show?

Back 26

1. Enhancers can be tissue specific

Front 27

What is the liver/albumin-specific enhancer?

Back 27

1. PE

2. Binds a specific liver transcription factor

3. Explains why albumin is only synthesized in the liver