DNA replication cannot take place without active primase. The broad long-term goal of this proposal is to learn enough about primase to develop it as a target to inhibit DNA replication in cancer cells. This proposal continues our studies of the structure, function and mechanism of primer RNA synthesis by E. coli primase and extends our studies to human primase. In the revised proposal, Specific Aim #1 is to study mechanism of movement of E. coli primase on DNA template. A hypothesis of a periodic, punctuated synthesis of pRNA by E. coli primase will be tested by measuring the processivity of primase and dissociation and rebinding of primase to the template after each step of synthesis (10/11 nt, 21/22 nt and 24/25 nt). A primase elongation mutant will be used for these experiments.
Specific Aim #2 is to analyze the active center of pRNA synthesis of E. coli primase. We will use Fe2+ cleavage and site-directed mutagenesis to localize amino acids that bind Mg2+ at the catalytic center and Zn2+ at the zinc finger. The DNA template binding sites will be analyzed using template oligonucleotides containing UV photoreactive nucleotides incorporated in specific positions. The exit pathway of the growing primer RNA chain will be similarly mapped by using photoreactive oligonucleotide primers. Changes in the conformation of primase during pRNA synthesis will be analyzed.
In Specific Aim #3, we will continue to study the role of SSB in pRNA synthesis. A primase/SSB physical interaction will be trapped by biochemical methods. The yeast two-hybrid system will be used to further analyze primase/SSB interaction. Interaction sites on both primase and SSB will be identified.
In Specific Aim #4, we will establish the domain structure of the human primase P49 and 58 subunits of DNA polymerase alpha. The active center of this two- protein system will be identified by ATP affinity cross-linking technique plus chemical cleavage. The function of these regions will be explored by site-directed mutagenesis.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM038292-18
Application #
6519259
Study Section
Microbial Physiology and Genetics Subcommittee 2 (MBC)
Program Officer
Wolfe, Paul B
Project Start
1986-08-01
Project End
2004-03-31
Budget Start
2002-04-01
Budget End
2003-03-31
Support Year
18
Fiscal Year
2002
Total Cost
$381,036
Indirect Cost
Name
New York University
Department
Biochemistry
Type
Schools of Medicine
DUNS #
City
New York
State
NY
Country
United States
Zip Code
10016
Rodina, Anna; Godson, G Nigel (2006) Role of conserved amino acids in the catalytic activity of Escherichia coli primase. J Bacteriol 188:3614-21
Godson, G N; Schoenich, J; Sun, W et al. (2000) Identification of the magnesium ion binding site in the catalytic center of Escherichia coli primase by iron cleavage. Biochemistry 39:332-9
Yajnik, V; Godson, G N (1993) Selective decay of Escherichia coli dnaG messenger RNA is initiated by RNase E. J Biol Chem 268:13253-60
Nesin, M; Svec, P; Lupski, J R et al. (1990) Cloning and nucleotide sequence of a chromosomally encoded tetracycline resistance determinant, tetA(M), from a pathogenic, methicillin-resistant strain of Staphylococcus aureus. Antimicrob Agents Chemother 34:2273-6
Hiasa, H; Sakai, H; Komano, T et al. (1990) Structural features of the priming signal recognized by primase: mutational analysis of the phage G4 origin of complementary DNA strand synthesis. Nucleic Acids Res 18:4825-31
Hiasa, H; Sakai, H; Tanaka, K et al. (1989) Mutational analysis of the primer RNA template region in the replication origin (oric) of bacteriophage G4: priming signal recognition by Escherichia coli primase. Gene 84:9-16
Almond, N; Yajnik, V; Svec, P et al. (1989) An Escherichia coli cis-acting antiterminator sequence: the dnaG nut site. Mol Gen Genet 216:195-203
Hiasa, H; Tanaka, K; Sakai, H et al. (1989) Distinct functional contributions of three potential secondary structures in the phage G4 origin of complementary DNA strand synthesis. Gene 84:17-22
Sakai, H; Hiasa, H; Iwamoto, K et al. (1988) Role of the potential secondary structures in phage G4 origin of complementary DNA strand synthesis. Gene 71:323-30
Nesin, M; Lupski, J R; Godson, G N (1988) Role of the 5' upstream sequence and tandem promoters in regulation of the rpsU-dnaG-rpoD macromolecular synthesis operon. J Bacteriol 170:5759-64