Human Syndromes with Defects in DNA repair

Question 1

skin cancer, UV sensitivity, neurological abnormalities; nucleotide excision repair is affected

Answer 1

Xeoderma pingmentosum

Question 2

leukemia, lymphoma, gamma ray sensitivity, genome instability; ATM protein, a protein kinase activated by double strand DNA breaks

Answer 2

Ataxia Telangiectasia

Question 3

Breast and ovarian cancer; repair by homologous recombination is affected

Answer 3

BRCA1

Question 4

UV sensitivity, developmental abonormalities; coupling of nucleotide excision repair to transcription.
accumulation of arrested transcription complexes at lesion sites; RNA pol is depleted

Answer 4

cockayne syndrome

Question 5

RNA polymerase is part of the repair process by stalling at DNA alterations (NER) during transcription and calls forth coupling proteins which direct excision repair machinery to these sites.

Answer 5

Transcription coupled repair

Question 6

involves removing a set of nucleotides, then ligating the strands back together; results in a deletion

Answer 6

nonhomologous end joining

Question 7

occurs after replication when nearby daughter DNA strand duplex can serve as template for repair

Answer 7

homologous recombination

Question 8

group of enzymes that form phosphodiester bonds between ribonucleotides

Answer 8

RNA polymerases

Question 9

transcribes rRNA genes

Answer 9

RNA pol 1

Question 10

transcribes all protein coding genes

Answer 10

RNA pol 2

Question 11

transcribes tRNA genes

Answer 11

RNA pol 3

Question 12

sequence of DNA nucleotides that signal the starting point for RNA synthesis

Answer 12

promter

Question 13

binds to TATA box and has a subunit called TBP TATA BINDING PROTEIN

Answer 13

TFIID

Question 14

blank determines when RNA pol will dissociate from the helix

Answer 14

Elongation factors

Question 15

where is RNA pol 2 phosphorylated?

Answer 15

C terminal domain

Question 16

snRNA + 7 protein subunits is

Answer 16

snRNP ribonucleotide protein

Question 17

sequence of RNA transcript mutation into an mRNA

Answer 17

1. 5’ end cap as it emerges from RNA polymerase
2. spliceosomes assemble to delineate intron/exon boundaries
3. when RNA pol reaches specific consensus sequences, special protiens are called forth that are eventually transferred to the 3’ end processing sequence.

Question 18

these are most abundant in the nucleus and help package mRNA

Answer 18

hnRNPs heterogenous nuclear ribonucleoproteins

Question 19

mRNA requires a (blank) similar to a key that opens the pore complex lock

Answer 19

nuclear transport receptor

Question 20

site of rRNA processing and incorporation of rRNAs into ribosome subunits
not membrane bound
contains rRNA genes, precursor rRNAs, mature rRNAs processing enzymes, partly assembled ribosomes

Answer 20

nucleolus

Question 21

converting the mRNA sequence into the language of amino acids is called

Answer 21

translation

Question 22

synthesized by RNA pol 3 in the nucleus

Answer 22

tRNA

Question 23

synthesized first as a precursor molecule with introns that must be removed

Answer 23

tRNA

Question 24

tRNA requires this for recognition and attachment of the correct amino acid to the 3’ end

Answer 24

aminoacyl-tRNA synthetase

Question 25

Protein is synthesized from….

Answer 25

N terminal end to C terminal end

Question 26

this ribosomal subunit is important for matching tRNA to codon on mRNA

Answer 26

small subunit

Question 27

this ribosomal subunit catalyzes the formation of peptide bonds between amino acids

Answer 27

large subunit

Question 28

hold tRNAs tightly if the anticodon forms base pairs with complementary codon on the mRNA

Answer 28

A and P site

Question 29

four major steps to chain elongation

Answer 29

tRNA biding
peptide bond formation
large subunit translocation
small subunit translocation

Question 30

mRNA is translated in

Answer 30

the 5’ to 3’ direction starting with amine terminus

Question 31

EFI and EF2 in eukaryotes speed up translation process

Answer 31

elongation factors

Question 32

responsible for catalytic activity in forming covalent peptide bonds not proteins

Answer 32

rRNAs

Question 33

initiates early protein folding; looks for stretches of hydrophobic amino acids which trigger ATP hydrolysis

Answer 33

HSP70

Question 34

aid in correcting incorrectly or incompletely folded protein

Answer 34

HSP60

Question 35

highly conserved eukaryotic protein with many functions

Answer 35

ubiquitin

Question 36

endocytosis

Answer 36

multiubiquitylation

Question 36

histone regulation

Answer 36

monoubiquitylation

Question 37

proteasomal degradation; DNA repair

Answer 37

polyubiquitylation

Question 38

surface amino acid sequences recognized by the enzymes

Answer 38

degrons

Question 39

recognize the ubiquitin’s on a protein and begin digestion

Answer 39

proteasomes