TY - JOUR
T1 - Human Ku70/80 associates physically with telomerase through interaction with hTERT
AU - Chai, Weihang
AU - Ford, Lance P.
AU - Lenertz, Lisa
AU - Wright, Woodring E.
AU - Shay, Jerry W.
PY - 2002/12/6
Y1 - 2002/12/6
N2 - Telomere length maintenance, an activity essential for chromosome stability and genome integrity, is regulated by telomerase- and telomere-associated factors. The DNA repair protein Ku (a heterodimer of Ku70 and Ku80 subunits) associates with mammalian telomeres and contributes to telomere maintenance. Here, we analyzed the physical association of Ku with human telomerase both in vivo and in vitro. Antibodies specific to human Ku proteins precipitated human telomerase in extracts from tumor cells, as well as from telomeraseimmortalized normal cells, regardless of the presence of DNA-dependent protein kinase catalytic subunit. The same Ku antibodies also precipitated in vitro reconstituted telomerase, suggesting that this association does not require telomeric DNA. Moreover, Ku associated with the in vitro translated catalytic subunit of telomerase (hTERT) in the absence of telomerase RNA (hTR) or telomeric DNA. The results presented here are the first to report that Ku associates with hTERT, and this interaction may function to regulate the access of telomerase to telomeric DNA ends.
AB - Telomere length maintenance, an activity essential for chromosome stability and genome integrity, is regulated by telomerase- and telomere-associated factors. The DNA repair protein Ku (a heterodimer of Ku70 and Ku80 subunits) associates with mammalian telomeres and contributes to telomere maintenance. Here, we analyzed the physical association of Ku with human telomerase both in vivo and in vitro. Antibodies specific to human Ku proteins precipitated human telomerase in extracts from tumor cells, as well as from telomeraseimmortalized normal cells, regardless of the presence of DNA-dependent protein kinase catalytic subunit. The same Ku antibodies also precipitated in vitro reconstituted telomerase, suggesting that this association does not require telomeric DNA. Moreover, Ku associated with the in vitro translated catalytic subunit of telomerase (hTERT) in the absence of telomerase RNA (hTR) or telomeric DNA. The results presented here are the first to report that Ku associates with hTERT, and this interaction may function to regulate the access of telomerase to telomeric DNA ends.
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U2 - 10.1074/jbc.M208542200
DO - 10.1074/jbc.M208542200
M3 - Article
C2 - 12377759
AN - SCOPUS:0037033062
SN - 0021-9258
VL - 277
SP - 47242
EP - 47247
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 49
ER -