PRI2/YKL045W Summary Help

Standard Name PRI2
Systematic Name YKL045W
Feature Type ORF, Verified
Description Subunit of DNA primase; DNA primase is required for DNA synthesis and double-strand break repair (1, 2 and see Summary Paragraph)
Name Description DNA PRImase
Chromosomal Location
ChrXI:353493 to 355079 | ORF Map | GBrowse
Gene Ontology Annotations All PRI2 GO evidence and references
  View Computational GO annotations for PRI2
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 6 genes
Classical genetics
Large-scale survey
reduction of function
52 total interaction(s) for 39 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 16
  • Affinity Capture-RNA: 3
  • Affinity Capture-Western: 2
  • Co-purification: 2
  • Reconstituted Complex: 3
  • Two-hybrid: 1

Genetic Interactions
  • Dosage Growth Defect: 1
  • Negative Genetic: 20
  • Positive Genetic: 1
  • Synthetic Growth Defect: 2
  • Synthetic Lethality: 1

Expression Summary
Length (a.a.) 528
Molecular Weight (Da) 62,262
Isoelectric Point (pI) 8.25
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrXI:353493 to 355079 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1587 353493..355079 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | E.C. | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000001528

PRI2 is an essential gene (3); it encodes a subunit of DNA polymerase alpha (4), formerly called DNA polymerase I (5; reviewed in 2, 6; also see 4). Yeast DNA polymerase alpha comprises four subunits, of MW 167 kD (Pol1p), 79 kD (Pol12p), 62 kD (Pri2p), and 48 kD (Pri1p). Polymerase alpha is required for DNA replication; it is involved both in initiation and in priming Okazaki fragments during lagging strand elongation. It has no associated proofreading exonuclease activity; the two smaller subunits form the primase activity that synthesizes short RNA primers in DNA replication. Pri2p increases the efficiency of RNA primer extension catalyzed by Pri1p on a DNA template (7). In yeast, DNA polymerase alpha activity is required for premeiotic DNA replication and sporulation and for double-strand break repair (8), but not for other DNA repair synthesis (9, 10).

Conditional mutations in PRI2 show altered DNA synthesis at the restrictive temperature (11), as well as increased mitotic intrachromosomal recombination and increased spontaneous mutation rates (12). DNA primase may also couple DNA replication to DNA repair, as a mutation in PRI2 (pri2-1) inhibits completion of double-strand break repair (8). All four subunits of DNA polymerase alpha are assembled throughout the cell cycle (13). In addition, affinity chromatography detects physical interactions between the polymerase and several other proteins (14), including Spt16p and Pob3p (15). Like many other genes encoding DNA replication proteins, PRI2 is transcribed during late G1 and S phases of the cell cycle; it is also highly expressed during premeiotic DNA synthesis (16). Though the mouse Pri2p homolog is very similar to the yeast protein, it cannot complement a pri2 mutation.

Last updated: 1999-05-07 Contact SGD

References cited on this page View Complete Literature Guide for PRI2
1) Foiani M, et al.  (1989) A single essential gene, PRI2, encodes the large subunit of DNA primase in Saccharomyces cerevisiae. Mol Cell Biol 9(7):3081-7
2) Burgers PM  (1998) Eukaryotic DNA polymerases in DNA replication and DNA repair. Chromosoma 107(4):218-27
3) Lucchini G, et al.  (1987) Yeast DNA polymerase--DNA primase complex; cloning of PRI 1, a single essential gene related to DNA primase activity. EMBO J 6(3):737-42
4) Plevani P, et al.  (1988) The yeast DNA polymerase-primase complex: genes and proteins. Biochim Biophys Acta 951(2-3):268-73
5) Burgers PM, et al.  (1990) Revised nomenclature for eukaryotic DNA polymerases. Eur J Biochem 191(3):617-8
6) Sugino A  (1995) Yeast DNA polymerases and their role at the replication fork. Trends Biochem Sci 20(8):319-23
7) Santocanale C, et al.  (1993) The isolated 48,000-dalton subunit of yeast DNA primase is sufficient for RNA primer synthesis. J Biol Chem 268(2):1343-8
8) Holmes AM and Haber JE  (1999) Double-strand break repair in yeast requires both leading and lagging strand DNA polymerases. Cell 96(3):415-24
9) Budd ME, et al.  (1989) DNA polymerase I is required for premeiotic DNA replication and sporulation but not for X-ray repair in Saccharomyces cerevisiae. Mol Cell Biol 9(2):365-76
10) Wang Z, et al.  (1993) DNA repair synthesis during base excision repair in vitro is catalyzed by DNA polymerase epsilon and is influenced by DNA polymerases alpha and delta in Saccharomyces cerevisiae. Mol Cell Biol 13(2):1051-8
11) Francesconi S, et al.  (1991) Mutations in conserved yeast DNA primase domains impair DNA replication in vivo. Proc Natl Acad Sci U S A 88(9):3877-81
12) Longhese MP, et al.  (1993) Conditional mutations in the yeast DNA primase genes affect different aspects of DNA metabolism and interactions in the DNA polymerase alpha-primase complex. Genetics 133(2):183-91
13) Ferrari M, et al.  (1996) Phosphorylation of the DNA polymerase alpha-primase B subunit is dependent on its association with the p180 polypeptide. J Biol Chem 271(15):8661-6
14) Miles J and Formosa T  (1992) Protein affinity chromatography with purified yeast DNA polymerase alpha detects proteins that bind to DNA polymerase. Proc Natl Acad Sci U S A 89(4):1276-80
15) Wittmeyer J and Formosa T  (1997) The Saccharomyces cerevisiae DNA polymerase alpha catalytic subunit interacts with Cdc68/Spt16 and with Pob3, a protein similar to an HMG1-like protein. Mol Cell Biol 17(7):4178-90
16) Johnston LH, et al.  (1990) Expression of the yeast DNA primase gene, PRI1, is regulated within the mitotic cell cycle and in meiosis. Mol Gen Genet 221(1):44-8