Tinker R L, Kassavetis G A, Geiduschek E P
Department of Biology and Center for Molecular Genetics, University of California, San Diego, La Jolla 92093-0634.
EMBO J. 1994 Nov 15;13(22):5330-7. doi: 10.1002/j.1460-2075.1994.tb06867.x.
The phage T4 gene 45 protein (gp45), Escherichia coli beta and the eukaryotic proliferating cell nuclear antigen (PCNA) function in replication as processivity factors of their corresponding DNA polymerases. The T4 gp45 also functions as the transcriptional activator that connects expression of viral late genes to DNA replication. DNA tracking is an essential component of the replication and transcription regulatory functions of T4 gp45. The ability of gp45, beta and PCNA to track along DNA has been analyzed by photocrosslinking. Each of these proteins must be loaded onto DNA by a species-specific assembly factor. For gp45 and beta, the density of traffic along DNA is determined by a dynamic balance between continuous protein loading and unloading, and is also dependent on interaction with the conjugate single-stranded DNA binding protein.
噬菌体T4基因45蛋白（gp45）、大肠杆菌β蛋白以及真核生物增殖细胞核抗原（PCNA）在复制过程中作为其相应DNA聚合酶的持续合成因子发挥作用。T4 gp45还作为转录激活因子，将病毒晚期基因的表达与DNA复制联系起来。DNA跟踪是T4 gp45复制和转录调控功能的重要组成部分。已通过光交联分析了gp45、β蛋白和PCNA沿DNA跟踪的能力。这些蛋白质中的每一种都必须由物种特异性组装因子加载到DNA上。对于gp45和β蛋白，沿DNA的移动密度由持续的蛋白质加载和卸载之间的动态平衡决定，并且还取决于与共轭单链DNA结合蛋白的相互作用。
