Maturation of newly replicated chromatin

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:5243965

Smith, P A

We undertook a study to obtain a clearer understanding of the maturation process in rat hepatoma tissue culture (HTC) cells. HTC cells were labeled with short pulses of (/sup 3/H) thymidine and chased with cold thymidine for varying lengths of time in order to identify newly synthesized DNA at different stages of the maturation process. Nuclei were isolated directly or after an extensive fixation with formaldehyde to prevent the dissociation of histones from the DNA. An analysis of the repeat lengths obtained from nascent and bulk chromatin revealed that there are two stages in the maturation of newly replicated chromatin in HTC cells. The first stage is relatively brief (< 5 min), involves the chromatin which is immediately adjacent to the replication fork, and is characterized by a diffuse organization of nucleosomes on nascent DNA. The second stage, which lasts from 5-30 minutes post-replication, is characterized by a normal repeat length for the nascent nucleosomes, which are more easily able to slide along the DNA than bulk nucleosomes, resulting in an apparently shorter nucleosomal repeat length.

• Research Organization: Iowa Univ., Iowa City (USA)
• OSTI ID: 5243965
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANIMALS
AZINES
CELL CONSTITUENTS
CELL NUCLEI
CHROMATIN
DISEASES
DNA REPLICATION
HEPATOMAS
HETEROCYCLIC COMPOUNDS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
MOLECULAR STRUCTURE
NEOPLASMS
NUCLEIC ACID REPLICATION
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PYRIMIDINES
RATS
RIBOSIDES
RODENTS
THYMIDINE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES