Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1994-10-12
pubmed:abstractText
Accelerated G1 transit in HeLa cells develops after a temporary inhibition of DNA synthesis in the previous generation. G1 acceleration has been found to be dependent on (1) the cell-cycle position at the time of the inhibition and (2) the duration of the inhibition. The degree of G1 acceleration correlates with the position in S-phase at which DNA synthesis is blocked. G1 transit time decreases gradually beginning with early S blocks and reaches a minimum when DNA synthesis is inhibited at mid S-phase. A minimum of 4 h continuous inhibition at this position resulted in maximum G1 acceleration. Unbalanced growth, i.e., the nonspecific increase in total protein or RNA levels that results from inhibition of DNA synthesis, did not correlate with the decrease in G1 transit time. On the other hand, one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed specific changes in four nuclear proteins of molecular weights 120, 66, 57, and 51 kDa in cells immediately following release from inhibition of DNA synthesis at mid S-phase. A Western blot analysis of cyclins D and E showed an increased accumulation of cyclin E at 0, 1, 5, 7, and 12 h following cell release from the mid S-phase block. Therefore, it is unlikely that changes in the ratio of protein/DNA or RNA/DNA are responsible for the decrease in G1 transit times as suggested by the unbalanced growth model of G1 acceleration. Instead, G1 acceleration may result from the accumulation during S-phase blockage, and subsequent retention through G2 and mitosis, of specific proteins required for cell transit through G1 in the next cell cycle.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-4827
pubmed:author
pubmed:issnType
Print
pubmed:volume
214
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
198-208
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Accelerated G1-transit following transient inhibition of DNA replication is dependent on two processes.
pubmed:affiliation
Section of Cancer Biology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri 63108.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.