Week 2

Question 1

PRC-1

Answer 1

polycomb repressive complex 1

-polycomb key subunit–> binds to H3K27me3

Question 2

PRC-2

Answer 2

key subunit EZH2– catalyzes methylation of H3K27 to Me2 and Me3

*H3K27Me3 then bound by PRC1

Question 3

Histone Variant H1*primary

Answer 3

chromatin compaction and repression

Question 4

Histone Varient H5

Answer 4

“super H1” in avian and amphibian erythrocytes

Question 5

Histone Variant H2Az

Answer 5

promoter regions, transcription regulation

Question 6

Histone Varient H2Ax

Answer 6

DNA Repair; phosphorylated–> gamma H2Ax, marker for DNA damage

Question 7

Histone Variant H3.3

Answer 7

transcription, active genes

Question 8

Histone Variant H4

Answer 8

no sequence variant, is a s-phase independent H4

Question 9

Histone Variant CENP-A

Answer 9

H3 variant- centromere function

Question 10

PARP-1

Answer 10

binds to nucleosomes like H1 and compacts chromatin, released via NAD+

Question 11

HMGB

Answer 11

Box, globular domains that are DBD

• have increased affinities for 4-way junction DNA
• non-sequence specific, but some can be (Lep1, SRY)
• role in lung formation

Question 12

HMGN

Answer 12

• non-sequence specific, small
• highly charged, have structure once bound to nucleosome, only in vertebrates
• *2 high-affinity binding sites

Question 13

HMGA

Answer 13

• AT hook, DNA binding motif, binds to heterochromatin
• bind to minor groove at AT hook
• bend DNA, suggested as “architectural factors” specific to formation of enhancer structures

Question 14

MeCP2

Answer 14

mutation will lead to Rett syndrome, 2nd most common form of mental retardation in females

Question 15

5 azacytidine (5azaC)

Answer 15

anticancer drug, encorporated into DNA

-5azaC–> 5aza2’deoxycitidine 5’ triP

Question 16

HP1

Answer 16

heterochromatin protein

-binds to Histone H3, methylates lys 9

Question 17

Su(var) 3-9:

Answer 17

methylates Histone H3K9, promotes binding of HP1

-may also bind to HDAC1

Question 18

HMGA

Answer 18

localized predominantly to heterochromatin

Question 19

Su(var)2-5

Answer 19

encodes HP1

Question 20

E(var)

Answer 20

enhancer of PEV, enhances when mutated, decreases formation of heterochromatin

Question 21

HI-C

Answer 21

-crosslink DNA, cut with restriction enzyme, fill ends and mark with biotin, ligate, purify and shear, pull down biotin, sequence with pair ends

Question 22

Tads

Answer 22

topologically associated proteins; may be separated by insulators