PCNA and DNA Polymerase δ Catalytic Subunit fromSchizosaccharomyces pombeDo Not Interact Directly

Tratner, Isabelle; Piard, Karine; Grenon, Muriel; Perderiset, Mylène; Baldacci, Giuseppe

doi:10.1006/bbrc.1997.6082

Cited by 18 publications

(21 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The present results are in full agreement with the report of a lack of interaction between S. cerevisiae PCNA and p125 (37). In those studies co-immunoprecipitation of yeast PCNA and p125 co-expressed in insect cells was initially investigated by using an antibody specific to either PCNA or p125 and confirmed by reciprocal experiments using the antibodies against the partner.…”

Section: Discussionsupporting

confidence: 93%

“…Binding studies using recombinant human p125 and PCNA have demonstrated direct interaction between these two polypeptides by protein overlay experiments using biotinylated PCNA and by biochemical cross-linking experiments (33); however, pulldown assays using PCNA-linked beads have yielded both positive (34) and negative (35) results with respect to the binding of PCNA and p125. Similar studies with S. cerevisiae (30,36) and S. pombe (37,38) pol ␦ failed to detect any interaction between PCNA and the catalytic subunits of the yeast enzymes. The small subunits of pol ␦ from both budding yeast (Pol31) and mammalian (p50) sources were found not to directly bind PCNA (30,33,34,36).…”

mentioning

confidence: 56%

See 1 more Smart Citation

Direct Interaction of Proliferating Cell Nuclear Antigen with the Small Subunit of DNA Polymerase δ

Lu¹,

Tan²,

Zhou³

et al. 2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

The interaction between proliferating cell nuclear antigen (PCNA) and DNA polymerase ␦ is essential for processive DNA synthesis during DNA replication/repair; however, the identity of the subunit of DNA polymerase ␦ that directly interacts with PCNA has not been resolved until now. In the present study we have used reciprocal co-immunoprecipitation experiments to determine which of the two subunits of core DNA polymerase ␦, the 125-kDa catalytic subunit or the 50-kDa small subunit, directly interacts with PCNA. We found that PCNA co-immunoprecipitated with human p50, as well as calf thymus DNA polymerase ␦ heterodimer, but not with p125 alone, suggesting that PCNA directly interacts with p50 but not with p125. A PCNA-binding motif, similar to the sliding clamp-binding motif of bacteriophage RB69 DNA polymerase, was identified in the N terminus of p50. A 22-amino acid oligopeptide containing this sequence (MRPFL) was shown to bind PCNA by far Western analysis and to compete with p50 for binding to PCNA in co-immunoprecipitation experiments. The binding of p50 to PCNA was inhibited by p21, suggesting that the two proteins compete for the same binding site on PCNA. These results establish that the interaction of PCNA with DNA polymerase ␦ is mediated through the small subunit of the enzyme.

show abstract

Section: Discussionsupporting

confidence: 93%

mentioning

confidence: 56%

Direct Interaction of Proliferating Cell Nuclear Antigen with the Small Subunit of DNA Polymerase δ

Lu¹,

Tan²,

Zhou³

et al. 2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…However, direct binding of PCNA to the large subunit as well as the second subunit of Pol ␦ has also been demonstrated (30 -33), although other studies failed to detect such interactions, suggesting that they are likely quite weak (10,24,31,(33)(34)(35). To determine to what extent the PCNA-binding domain of Pol32 is responsible for the interaction between the threesubunit Pol ␦ and PCNA, we carried out native gel electrophoresis of several reconstituted Pol ␦ complexes as well as surface plasmon resonance analysis of one particular mutant Pol ␦-10.…”

Section: Resultsmentioning

confidence: 99%

The Pol32 Subunit of DNA Polymerase δ Contains Separable Domains for Processive Replication and Proliferating Cell Nuclear Antigen (PCNA) Binding

Johansson¹,

Garg

Burgers

2004

Journal of Biological Chemistry

169

163

View full text Add to dashboard Cite

We have carried out a domain analysis of POL32, the third subunit of Saccharomyces cerevisiae DNA polymerase ␦ (Pol ␦). Interactions with POL31, the second subunit of Pol ␦, are specified by the amino-terminal 92 amino acids, whereas interactions with the replication clamp proliferating cell nuclear antigen (PCNA, POL30) reside at the extreme carboxyl-terminal region. Pol32 binding, in vivo and in vitro, to the large subunit of DNA polymerase ␣, POL1, requires the carboxyl-proximal region of Pol32. The amino-terminal region of Pol32 is essential for damage-induced mutagenesis. However, the presence of its carboxyl-terminal PCNA-binding domain enhances the efficiency of mutagenesis, particularly at high loads of DNA damage. In vitro, in the absence of effector DNA, the PCNA-binding domain of Pol32 is essential for PCNA-Pol ␦ interactions. However, this domain has minimal importance for processive DNA synthesis by the ternary DNA-PCNA-Pol ␦ complex. Rather, processivity is determined by PCNA-binding domains located in the Pol3 and/or Pol31 subunits. Using diagnostic PCNA mutants, we show that during DNA synthesis the carboxyl-terminal domain of Pol32 interacts with the carboxyl-terminal region of PCNA, whereas interactions of the other subunit(s) of Pol ␦ localize largely to a hydrophobic pocket at the interdomain connector loop region of PCNA.Accurate and efficient DNA replication in eukaryotic cells requires the participation of at least three essential DNA polymerases, Pol ␣, 1 Pol ␦, and Pol ⑀. Several lines of evidence indicate that Pol ␣ and Pol ␦ function in the initiation and elongation of Okazaki fragment synthesis, respectively (reviewed in Refs. 1 and 2). Replication of the C-A-rich strand at telomeres, by nature a lagging strand process, is also dependent on these two DNA polymerases (3). Under special circumstances, e.g. in a yeast mutant carrying a deletion of the Pol ⑀ polymerization domain, Pol ␦ probably also carries out leading strand synthesis (4 -6). However, analyses of exonuclease-deficient DNA polymerase ␦ and ⑀ strains have revealed a strand specificity of mutation rates and spectra that is most easily reconciled with a dominant role for Pol ⑀ in leading strand synthesis (7-9).Pol ␦ from Saccharomyces cerevisiae consists of three subunits of 125, 55, and 40 kDa (10). An additional small fourth subunit is found in the enzymes from Schizosaccharomyces pombe and human, (11-13). Deletion of the Cdm1 gene for the fourth subunit in S. pombe is genetically silent in the absence of additional mutations in Cdc1 encoding the second subunit (14). However, efficient overproduction of soluble fission yeast Pol ␦ in baculovirus required the presence of Cdm1 (15). The analogous p12 human subunit could be reconstituted with the human three-subunit Pol ␦ into a stable four-subunit enzyme, and significantly stimulated its activity (13).The catalytic subunit and the second subunit, encoded in S. cerevisiae by the POL3 and POL31 (HYS2) genes, respectively, are highly conserved in eukaryotes. The genes are also...

show abstract

“…PI3K signaling is activated in human cancers via several different mechanisms, including direct mutational activation or amplification of genes encoding key components of the PI3K pathway such as PIK3CA and AKT1 or loss of PTEN (3,9). The role of several PI3K subunits in tumor development and metastasis has been well-investigated, including p110a, p110b, p85a, and p85b (10)(11)(12). But even now, the role and function of PIK3R3 in tumor metastasis still remain to be little known.…”

Section: Introductionmentioning

confidence: 99%

PIK3R3 Induces Epithelial-to-Mesenchymal Transition and Promotes Metastasis in Colorectal Cancer

Wang

et al. 2014

Molecular Cancer Therapeutics

View full text Add to dashboard Cite

Class IA PI3K plays an essential role in the invasion and metastasis of cancer. However, the mechanisms and specific functions of PI3K isoforms in tumor invasion and metastasis are not fully understood. We evaluated the role of PIK3R3, a PI3K regulatory subunit encoded by the PIK3R3 gene, in colorectal cancer invasion and metastasis. Clinical specimens and cell lines data show that the expression level of PIK3R3 is associated with colorectal cancer metastasis. Overexpression of PIK3R3 increases tumor migration and invasion in vitro and promotes metastasis of colorectal cancers in vivo. Furthermore, we investigated that the overexpression of PIK3R3 depends on SNAI2, inducing significant epithelial-to-mesenchymal transition (EMT). Downregulation of PIK3R3 reverses this process, which possibly contributes to the enhanced invasive and metastasizing abilities of colorectal cancer cells. In this study, we found that PIK3R3 plays an important role in colorectal cancer metastasis and might be a potential and specific target for therapies against metastatic colorectal cancer.

show abstract

PCNA and DNA Polymerase δ Catalytic Subunit fromSchizosaccharomyces pombeDo Not Interact Directly

Cited by 18 publications

References 46 publications

Direct Interaction of Proliferating Cell Nuclear Antigen with the Small Subunit of DNA Polymerase δ

Direct Interaction of Proliferating Cell Nuclear Antigen with the Small Subunit of DNA Polymerase δ

The Pol32 Subunit of DNA Polymerase δ Contains Separable Domains for Processive Replication and Proliferating Cell Nuclear Antigen (PCNA) Binding

PIK3R3 Induces Epithelial-to-Mesenchymal Transition and Promotes Metastasis in Colorectal Cancer

Contact Info

Product

Resources

About