Age-related analysis of EcoRI generated satellite DNA-containing chromatin of rat liver.
EcoRI digestion of nuclei and their subsequent lysis with EDTA solubilizes 45% and 36% of chromatin DNA from the liver of young (18 +/- 2 weeks) and old (100 +/- 5 weeks) rats, respectively. After hybridization with 185 bp rat satellite I DNA, these soluble fractions are found to be enriched in specific DNA sequences such as satellite DNA. Besides regular repeat pattern, a major portion of the satellite chromatin forms higher order organization. Digestion kinetics confirms condensation of satellite DNA-containing chromatin similar to that of bulk chromatin in old age. Furthermore, densitometric scanning of the slot-blot of soluble chromatin fractions reveals loss of satellite DNA in the old. However, an increase in the linker histone H1 and its subfraction H1zero in the satellite DNA-enriched fraction of chromatin from old rats suggests greater compaction. These results provide the first evidence that the satellite DNA-containing chromatin differs in the liver of young and old rats.
Chaurasia
P
P
Biochemistry & Molecular Biology Laboratory, Banaras Hindu University, Varanasi, India.
Mukherjee
S
S
Thakur
M K
MK
D000375:Aging / Q000235:genetics*; D000818:Animals; D015139:Blotting, Southern; D002467:Cell Nucleus / Q000737:chemistry; D002843:Chromatin / Q000737:chemistry*; D004276:DNA, Satellite / Q000032:analysis*; D015246:Deoxyribonuclease EcoRI; D006657:Histones / Q000032:analysis; D008099:Liver / Q000737:chemistry*; D008297:Male; D009693:Nucleic Acid Hybridization; D051381:Rats; D017208:Rats, Wistar; D012995:Solubility
D002843:Chromatin; D004276:DNA, Satellite; D006657:Histones; D015246:Deoxyribonuclease EcoRI