中文摘要：

增殖细胞核抗原（proliferating cell nuclear antigen，PcNA）是真核细胞DNA复制过程中的一个关键因子，作为DNA聚合酶6的辅助因子而发挥功能。此外，PCNA亦能与多种蛋白因子结合而参与DNA修复、细胞周期调控、细胞凋亡等生命过程。DNA修复可维持细胞基因组的稳定性，为细胞存活和正常生长所必需。本文就PCNA在DNA的错配修复、切除修复、跨损伤DNA合成修复、重组修复等过程中所担负的角色做一综述。

英文摘要：

Proliferating cell nuclear antigen （PCNA） is a key component of the eukaryotic replication machinery, and functions as a DNA polymerase delta processivity factor. Apart from its classic role in DNA replication, PCNA also interacts with various protein factors to modulate many cellular events involved in DNA repair, cell cycle regulation, and apoptosis. DNA repair is crucial for maintaining genome stability and essential for cell survival and optimal growth. This paper will summarize the role of PCNA in DNA mismatch repair, excision repair, translesion synthesis, and recombinational repair.