Peck V M, Gerner E W, Cress A E
Department of Radiation Oncology, Arizona Cancer Center, University of Arizona, Tucson 85724.
Nucleic Acids Res. 1992 Nov 11;20(21):5779-84. doi: 10.1093/nar/20.21.5779.
Genetic and biochemical evidence suggests there are at least three DNA polymerases required for replication in eukaryotic cells. However, Drosophila embryonic cells have a very short duration S phase which is regulated differently. To address the question of whether embryos utilize different DNA polymerases, we employed Mono Q anion exchange chromatography to resolve the DNA polymerase activities. Two types of DNA polymerase, DNA polymerase delta and DNA polymerase alpha, were distinguished by: 1. copurification of DNA primase or 3'-5'exonuclease activities; 2. immunoblot analysis with alpha-specific polyclonal antisera; 3. sensitivity to aphidicolin and BuPdGTP; and 4. processivity measurements with and without Proliferating Cell Nuclear Antigen. These observations suggest that Drosophila embryos, similar to nonembryonic cells, have both alpha- and delta-type DNA polymerases.
遗传和生化证据表明，真核细胞复制至少需要三种DNA聚合酶。然而，果蝇胚胎细胞的S期持续时间非常短，且调控方式不同。为了解决胚胎是否利用不同DNA聚合酶这一问题，我们采用单Q阴离子交换色谱法来解析DNA聚合酶活性。通过以下几点区分出了两种类型的DNA聚合酶，即DNA聚合酶δ和DNA聚合酶α：1. DNA引物酶或3'-5'核酸外切酶活性的共纯化；2. 用α特异性多克隆抗血清进行免疫印迹分析；3. 对阿非迪霉素和BuPdGTP的敏感性；4. 在有和没有增殖细胞核抗原的情况下进行持续合成能力测量。这些观察结果表明，果蝇胚胎与非胚胎细胞相似，同时拥有α型和δ型DNA聚合酶。
