Proliferating cell nuclear antigen (PCNA/cyclin): Review and some new findings

Abstract

PCNA/cyclin was originally described in proliferating mammalian cells as a nuclear protein with an apparent molecular weight of 33, 000–36,000, and recently found to be a DNA polymerase-delta auxiliary protein. When the cDNA for PCNA/cyclin was cloned and analyzed, it was found that the protein consisted of 261 amino acids with a calculated molecular weight of 28,700 and the amino acid sequence was well conserved during evolution both in animal and plant kingdoms. The highly homologous nature of PCNA/cyclin suggests that the protein plays an essential role in DNA replication in eukaryotes. © 1989, JAPAN SOCIETY OF HISTOCHEMISTRY AND CYTOCHEMISTRY. All rights reserved.