Publication Date:
2002-03-30
Description:
Primary human cells in culture invariably stop dividing and enter a state of growth arrest called replicative senescence. This transition is induced by programmed telomere shortening, but the underlying mechanisms are unclear. Here, we report that overexpression of TRF2, a telomeric DNA binding protein, increased the rate of telomere shortening in primary cells without accelerating senescence. TRF2 reduced the senescence setpoint, defined as telomere length at senescence, from 7 to 4 kilobases. TRF2 protected critically short telomeres from fusion and repressed chromosome-end fusions in presenescent cultures, which explains the ability of TRF2 to delay senescence. Thus, replicative senescence is induced by a change in the protected status of shortened telomeres rather than by a complete loss of telomeric DNA.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Karlseder, Jan -- Smogorzewska, Agata -- de Lange, Titia -- AG16643/AG/NIA NIH HHS/ -- CA76027/CA/NCI NIH HHS/ -- New York, N.Y. -- Science. 2002 Mar 29;295(5564):2446-9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory for Cell Biology and Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11923537" target="_blank"〉PubMed〈/a〉
Keywords:
Antigens, Polyomavirus Transforming/genetics/metabolism
;
*Cell Aging
;
*Cell Division
;
Cell Line
;
Cells, Cultured
;
DNA/*metabolism
;
DNA-Binding Proteins/genetics/*metabolism
;
Humans
;
Oncogene Proteins, Viral/genetics/metabolism
;
Papillomavirus E7 Proteins
;
*Repressor Proteins
;
Retinoblastoma Protein/metabolism
;
Retroviridae/genetics
;
Telomere/metabolism/*physiology
;
Telomeric Repeat Binding Protein 2
;
Transformation, Genetic
;
Tumor Suppressor Protein p53/metabolism
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
Permalink
