Ultraviolet damage and nucleosome folding of the 5S ribosomal RNA gene.
- Washington State University
- ASSOC WESTERN UNIVERSITY
- BATTELLE (PACIFIC NW LAB)
- VISITORS
The Xenopus borealis somatic 5S ribosomal RNA gene was used as a model system to determine the mutual effects of nucleosome folding and formation of ultraviolet (UV) photoproducts (primarily cis-syn cyclobutane pyrimidine dimers, or CPDs) in chromatin. We analyzed the preferred rotational and translational settings of 5S rDNA on the histone octamer surface after induction of up to 0.8 CPD/nucleosome core (2.5 kJ/m(2) UV dose). DNase I and hydroxyl radical footprints indicate that UV damage at these levels does not affect the average rotational setting of the 5S rDNA molecules. Moreover, a combination of nuclease trimming and restriction enzyme digestion indicates the preferred translational positions of the histone octamer are not affected by this level of UV damage. We also did not observe differences in the UV damage patterns of irradiated 5S rDNA before or after nucleosome formation, indicating there is little difference in the inhibition of nucleosome folding by specific CPD sites in the 5S rRNA gene. Conversely, nucleosome folding significantly restricts CPD formation at all sites in the three helical turns of the nontranscribed strand located in the dyad axis region of the nucleosome, where DNA is bound exclusively by the histone H3-H4 tetramer. Finally, modulation of the CPD distribution in a 14 nt long pyrimidine tract correlates with its rotational setting on the histone surface, when the strong sequence bias for CPD formation in this tract is minimized by normalization. These results help establish the mutual roles of histone binding and UV photoproducts on their formation in chromatin.
- Research Organization:
- Pacific Northwest National Lab., Richland, WA (US)
- Sponsoring Organization:
- US Department of Energy (US)
- DOE Contract Number:
- AC06-76RL01830
- OSTI ID:
- 15003117
- Report Number(s):
- PNWD-SA-5349
- Journal Information:
- Biochemistry, Journal Name: Biochemistry Journal Issue: 3 Vol. 39
- Country of Publication:
- United States
- Language:
- English
Similar Records
DNA damage can alter the stability of nucleosomes: Effects are dependent on damage type.
Linker histones H1 and H5 prevent the mobility of positioned nucleosomes
UV-induced formation of pyrimidine dimers in nucleosome core DNA is strongly modulated with a period of 10. 3 bases
Journal Article
·
Mon Mar 17 23:00:00 EST 1997
· Proceedings of the National Academy of Sciences of the United States of America
·
OSTI ID:1525973
Linker histones H1 and H5 prevent the mobility of positioned nucleosomes
Journal Article
·
Tue Oct 25 00:00:00 EDT 1994
· Proceedings of the National Academy of Sciences of the United States of America; (United States)
·
OSTI ID:6701355
UV-induced formation of pyrimidine dimers in nucleosome core DNA is strongly modulated with a period of 10. 3 bases
Journal Article
·
Thu Oct 01 00:00:00 EDT 1987
· Proc. Natl. Acad. Sci. U.S.A.; (United States)
·
OSTI ID:5624982