Unformatted text preview: including the role each individual protein above plays, what type of
damage is repaired, and the steps that lead to this repair. NER!
Nucleotide Excision Repair!
a. !Damage recognition: XPA, RPA, !
!XPC-TRIIH or hHR23B (GG)!
b. !XPB (3 ->5 helicase) & XPD !
!(5 ->3 helicase) of TFIIH:!
!ATP-dep DNA unwinding ~25nt!
!PIC1 bubble formation !
!XPG replaces XPC !
c. 5 (XPF-ERCC1) & 3 XPG
d. release -> 24-32 nt fragment!
e. DNA pol delta/epsilon , PCNA;
! This system repairs large bulky distortions to DNA such as Thymine cyclobutyl-dimers.
Defects in this DNA repair system lead to what disease, and what are some of its
symptoms? xeroderma pigmentosum (XP) which is characterized by sensitivity to
sunlight and high rates of skin cancer 12 Initials:___________________
33. 15 pts
A. Starting with 5/-ATP in a messenger RNA molecule, draw with chemical
structures, the reaction(s) catalyzed by capping enzyme,
Eukaryotic 5'-Capping Reactions
N N N N
-O O N O PO PO P O- O- 5/ O- O -O H H O H
OH N 5/
H -O N O PO P O- N P
OO O P OH
H –O N
NH2 O- O O
H 1. RNA triphosphatase H
–O O O
O 3/ O O...
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This test prep was uploaded on 03/23/2014 for the course CHEMISTRY 4141 taught by Professor Jonklaas during the Spring '13 term at Baylor.
- Spring '13