Specific interactions of three proliferating cell nuclear antigens with replication-related proteins in Aeropyrum pernix.
Proliferating cell nuclear antigen (PCNA) is a well-known multifunctional protein involved in eukaryotic and archaeal DNA transactions. The homotrimeric PCNA ring encircles double-stranded DNA within its central hole and tethers many proteins on DNA. Plural genes encoding PCNA-like proteins have been found in the genome sequence of crenarchaeal organisms. We describe here the biochemical properties of the three PCNAs, PCNA1, PCNA2 and PCNA3, from the hyperthermophilic archaeon, Aeropyrum pernix. PCNA2 can form a trimeric structure by itself, and it also forms heterotrimeric structures with PCNA1 and PCNA3. However, neither PCNA1 nor PCNA3 can form homotrimers. The DNA synthesis activity of DNA polymerase I and II, the endonuclease activity of FEN1, and the nick-sealing activity of DNA ligase were stimulated by the complex of PCNA2 and 3 or PCNA1, 2 and 3. These results suggest that the heterotrimeric PCNA at least including PCNA2 and 3 function as the clamp in the replisome. However, PCNA2 is the most abundant in the cells throughout the growth stages among the three PCNAs, and therefore, PCNA2 may perform multitasks by changing complex composition.
Imamura
Kaori
K
Department of Genetic Resources Technology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Fukuoka-shi, Fukuoka 812-8581, Japan.
Fukunaga
Kenzo
K
Kawarabayasi
Yutaka
Y
Ishino
Yoshizumi
Y
D041522:Aeropyrum / Q000201:enzymology / Q000378:metabolism*; D019843:Archaeal Proteins / Q000378:metabolism*; D002850:Chromatography, Gel; D053837:DNA Cleavage; D011088:DNA Ligases / Q000378:metabolism; D004256:DNA Polymerase I / Q000378:metabolism; D004257:DNA Polymerase II / Q000378:metabolism; D004260:DNA Repair; D004261:DNA Replication; D019641:DNA, Archaeal / Q000096:biosynthesis; D045585:Flap Endonucleases / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism*; D011485:Protein Binding; D021122:Protein Subunits / Q000378:metabolism; D051818:Replication Protein C / Q000378:metabolism
D019843:Archaeal Proteins; D019641:DNA, Archaeal; D018809:Proliferating Cell Nuclear Antigen; D021122:Protein Subunits; D004256:DNA Polymerase I; D004257:DNA Polymerase II; D045585:Flap Endonucleases; D051818:Replication Protein C; D011088:DNA Ligases