Dna Mutations/repair

Front 1

"The Notable Surgeon was not able to operate because there was no table." example of?

Back 1

frameshift mutation=insertion/deletion

in-frame: insertion/deletion in multiples of 3

Front 2

Missense mutation

Back 2

alters codon, change amino acid which changes protein

Front 3

nonsense mutation

Back 3

premature stop codon

"non"="no" protein

Front 4

silent mutation

Back 4

wobble bp in 3rd AA. no change in amino acid sequence

Front 5

Tandem repeated insertion
examples?

Back 5

DNA polymerase "slips", creates loop, if not fixed, extra loop---> a longer template strand later on when daughter strand becomes a new template strand

fragile X, huntington's disease

Front 6

Types of Spontaneous Mutations

Back 6

1)incorrect base pairing (substitutions)
2) Tautomers-interconversion of isomers due to proton arrangement
3) Deamination of Cytosine--> Uracil (doesn't belong in DNA, can get fixed)
Deamination of 5-MCG to Thymine
4) Depurination=removal of purine base by hydrolysis of gylcosidic bond-->AP site

Front 7

Depurination

Back 7

removal of purine base by hydrolysis of glycosidic bond produces apurinic (AP) site

leads to deletions, transitions/transversions
strand breaks

Front 8

Substitutions: Transition vs. Tranversion

Back 8

transition: Pur to Pur, Pyr to Pyr ("s"="same")

tranversion= Pur to Pyr, Pyr to Pur

Front 9

Deamination (spontaneous)

Back 9

Cytosine-->uracil (catchable)

5 methylcytosine -->thymine

Front 10

Tautomers. give an example.

Back 10

interconversion of isomers by proton arrangements.

ex) cytosine will bind onto adenine tautomer=bad base pairing

Front 11

6 Types of Induced mutations

Back 11

environmental

-deamination by HNO2
-Alkylating Agents-addition of m/ehtyl groups. cause transition and depurination
-Intercalating Agents: aromatic molecules "stretch" double helix--->insertions
-Addition of Bulky chemical group (cigarette smoke)
-Free Radicals-ROS makes OH=highly reactive=tranversions, strand breaks, deletions
-UV light=intrastrand formation of thymine dimers=distorts double helix

Some "free and radical" dudes were hanging out in the "sun", when some Alkyl and Intercalating Agents" came up and made them carry these "bulky boxes of cigarrettes". the dudes said "de-ammmnit!"

Front 12

Exposure to UV light

Back 12

intrastrand formation of thymine dimers in same strand. distorts double helix and impairs DNA replication/transcription

Front 13

Free Radicals

Back 13

single unpaired electron->ROS, OH=highly reactive molecules that damage DNA, lipids, proteins

tranversions, deletions, strand breaks

Front 14

Intercalating Agents

Back 14

aromatic molecules that insert btw bases and stretch the double helix=insertions

intercalating agents smell funny

Front 15

Alkylating agents

Back 15

add methyl/ethyl groups covalently, can cause depurination or transition

alky agents have methyl groups makes them less pure and transitions them

Front 16

Hereditary Breast Cancer

Back 16

mutations in the BRCA1 and BRCA2 genes involved in recombination repair of double strand breaks in DNA

Front 17

Recombination Repair. what is it/what mutation is repaired? what are the key components in repair?

Back 17

DNA double strand breaks, invading of other strand to use as a template


As RUVen is learning her ABCs, (RuvA [Rad15], RuvB, RuvC) her double stranded pigtails break and we but them back on the wrong pigtails (double strand breaks) and (recombinatorial repair)

Front 18

Nucleotide Excision Repair

Back 18

distortion or "lesions" of double helix repaired via Excinuclease Complex

DNA Polymerase B=fill in gap
Ligase=seal DNA strand

Front 19

what is Transcription-Coupled Repair, and what is involved?
why is it important?

Back 19

CSA/CBA stall stop RNA Polymerase where there is Damage in template DNA

once transcrip is stopped, kicks out RNA polymerase and recruits excinuclease complex to fix.

important because you repair the the genes you are using/transcribing. the important genes

Front 20

Exinuclease Complex has 3 important things.

Back 20

-proteins that recognize lesions/damage

-helicase to unwind DNA in damaged region

-5', 3' endonucleases that cleave/excise strand on either side of DNA

Nucleotide Excision Repair
DNA-kid named Nucleotide, has these lesions, bully "exin" puts him on the swing, winds/unwinds him up, then finds the lesions, and cut them out with his "endonuc knife"

Front 21

Base Excision Repair

Back 21

BER=used to recognize and remove single mutated base

1) DNA Glycosylases-recognize/remove (poke/prods, recognizes bad bp, breaks N-glycosidic bond)

2) AP Endonuclease=cuts backbone (breaks DNA backbone via cleaving phosphodiester bond)

3) Deoxyribosephophodiesterase=removes deoxyribose/create free 3'OH and 5'Pi

DNA Polymerase/Ligase=Fills gap/seals DNA strand

Front 22

Mismatch pair. what enzymes are used to recognize? excise? fill? and seal?

Back 22

recognize/repair mismatched pair DURING DNA replication (prokary/eukary) via

MutS (hMSH2)=recognition
MutL=(hMLH1)=excision


"M"is"M"atch="M"ut S and "M"ut L
S=SSSee here!
L=imagine L inserting into sequence/popping it out