ISSN:
0263-6484
Keywords:
Nuclear matrix
;
DNA polymerase α
;
processivity
;
activity
;
heat stabilization
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
We have investigated whether or not ATP or other nucleoside di- and trisphosphates (including some nonhydrolysable ATP analogues) can stimulate the activity and/or the processivity of DNA polymerase α associated with the nuclear matrix obtained from HeLa S3 cell nuclei that had been stabilized at 37°C prior to subfractionation, as has been reported previously for DNA polymerase α bound to the nuclear matrix prepared from 22-h regenerating rat liver. We have found that HeLa cell matrix-associated DNA polymerase α activity could not be stimulated at all by ATP or other nucleotides, a behaviour which was shared also by DNA polymerase α activity that solubilizes from cells during the isolation of nuclei and that is thought to be a form of the enzyme not actively engaged in DNA replication. Moreover, the processivity of matrix-bound DNA polymerase α activity was low (〈 10 nucleotides). These results were obtained with the matrix prepared with either 2M NaCl or 0·25 M (NH4)2SO4 and led us to consider that a 37° incubation of isolated nuclei renders resistant to high-salt extraction a form of DNA polymerase α which is unlikely to be involved in DNA replication in vivo.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cbf.290120208
