Effect of 3' exonuclease activity of polymerase on extension of phosphorothioate-modified primers.
- Author:
Zi-fen GUO
1
;
Lin-ling CHEN
;
Jia ZHANG
;
Cui-ying PENG
;
Xiang-dong YANG
;
Xu ZHANG
;
Shu-ya HE
;
Duan-fang LIAO
;
Kai LI
Author Information
- Publication Type:Journal Article
- MeSH: DNA Primers; chemistry; genetics; Exonucleases; metabolism; Humans; Phosphorothioate Oligonucleotides; chemistry; genetics; Polymerase Chain Reaction; Polymorphism, Single Nucleotide
- From: Chinese Journal of Medical Genetics 2003;20(4):328-330
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo determine whether 3'phosphorothioate-modified-2 terminal mismatched primers can turn off DNA polymerization mediated by Exo(+) polymerase.
METHODSTwo-directional primer extension was performed using polymerase with and without 3' exonuclease activity. The effects of unmodified primers and 3' phosphorothioate-modified primers on primer extension were evaluated.
RESULTSExo(-) polymerase yielded products from matched and mismatched primers regardless of their modification. However, 3' phosphorothioate-modified primers with a single base mismatch at -2 position worked similarly to the terminal (-1) mismatched primers in triggering the novelly reported "off-switch" of Exo(+) polymerase.
CONCLUSIONThese data suggested that the "off-switch" can be of enormous application in the diagnosis of single gene diseases and in the association studies by single nucleotide polymorphism screening.
