PMID- 6224796
OWN - NLM
STAT- MEDLINE
DCOM- 19831028
LR  - 20210210
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 258
IP  - 18
DP  - 1983 Sep 25
TI  - Changes in chromatin structure at the replication fork. DNase I and 
      trypsin-micrococcal nuclease effects on approximately 300- and 150-base pair 
      nascent DNAs.
PG  - 11274-9
AB  - DNase I, trypsin, and micrococcal nuclease are used to further probe the 
      structure of nascent deoxyribonucleoprotein (DNP) fractions which appear after in 
      vivo 20-s pulse labeling of sea urchin embryos with [3H]thymidine. We present 
      evidence that the large nascent DNP which protects the approximately 300-base 
      pair large nascent DNA consists of at least one nucleosome core. This is based on 
      fractionation in denaturing polyacrylamide gels of DNA extracted from large 
      nascent DNP fractions of a micrococcal nuclease + DNase I digest of nuclei. The 
      data also suggest the existence of a DNase I-hypersensitive site(s) within the 
      large nascent DNP; this is consistent with the hypothesis that the latter 
      consists of closely packed dinucleosome cores. Histone H1 and non-histone 
      proteins do not account for the previously reported unusual hyperresistance of 
      the large nascent DNA against micrococcal nuclease. The protection offered this 
      approximately 300-base pair nascent DNA was not eliminated by an 0.2-microgram/ml 
      trypsin pretreatment which removes the above proteins from the chromatin. 
      However, 5-10 micrograms/ml of trypsin, which remove a portion of the NH2 termini 
      of the four core histones of nucleosomes, eliminate the hyperresistance of the 
      large nascent DNA to subsequent micrococcal nuclease digestion, while nascent and 
      bulk monomer DNAs remain unaffected. This indicates histone-histone and/or 
      histone-DNA interactions within the large nascent DNP which differ from those of 
      nascent and bulk mononucleosome cores.
FAU - Galili, G
AU  - Galili G
FAU - Levy, A
AU  - Levy A
FAU - Jakob, K M
AU  - Jakob KM
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Chromatin)
RN  - 0 (Histones)
RN  - EC 3.1.- (Endodeoxyribonucleases)
RN  - EC 3.1.21.1 (Deoxyribonuclease I)
RN  - EC 3.1.31.1 (Micrococcal Nuclease)
RN  - EC 3.4.21.4 (Trypsin)
SB  - IM
MH  - Animals
MH  - Base Sequence
MH  - Chromatin/*ultrastructure
MH  - Deoxyribonuclease I
MH  - Endodeoxyribonucleases/*metabolism
MH  - Histones/metabolism
MH  - Micrococcal Nuclease/*metabolism
MH  - Sea Urchins
MH  - Trypsin/*metabolism
EDAT- 1983/09/25 00:00
MHDA- 1983/09/25 00:01
CRDT- 1983/09/25 00:00
PHST- 1983/09/25 00:00 [pubmed]
PHST- 1983/09/25 00:01 [medline]
PHST- 1983/09/25 00:00 [entrez]
AID - S0021-9258(17)44414-0 [pii]
PST - ppublish
SO  - J Biol Chem. 1983 Sep 25;258(18):11274-9.