Polynucleotides encoding RPA4/RPA32 hybrid polypeptides
Disclosed are polynucleotides and polypeptides that are useful for assessing and modulating cell proliferation. The polynucleotides may comprise coding regions for RPA4 and RPA4/RPA32 hybrid polypeptides. The polynucleotides may be used in gene vectors for modulating cell proliferation in a patient in need thereof. Diagnostic methods related to assaying RPA4 expression in test samples in order to detect proliferating or cancerous cells also are disclosed.
1. An isolated polynucleotide comprising a coding sequence for an replication protein A 32 (RPA32) variant polypeptide having at least 96% amino acid sequence identity to SEQ ID NO:7, wherein the polypeptide binds to at least one of replication protein A 1 (RPA1) and replication protein A 3 (RPA3).
2. The isolated polynucleotide of claim 1 , wherein the encoded Polypeptide comprises SEQ ID NO:7.
3. The isolated polynucleotide of claim 1 , wherein the encoded Polypeptide forms a complex with RPA1 and RPA3.
4. The isolated polynucleotide of claim 1 , wherein the encoded Polypeptide binds single stranded nucleic acid.
5. The isolated polynucleotide of claim 1 , wherein the encoded Polypeptide inhibits proliferation of human cells.
6. The isolated polynucleotide of claim 1 , wherein the encoded Polypeptide comprises SEQ ID NO:3.
7. The isolated polynucleotide of claim 6 , wherein the encoded Polypeptide comprises SEQ ID NO:3 at a region from amino acid 108 to amino acid 123 of the encoded polypeptide.
8. The isolated polynucleotide of claim 1 , wherein the polypeptide Comprises two or more basic amino acid residues within a region from amino acid 108 to amino acid 123 of the encoded polypeptide.
9. The isolated polynucleotide of claim 1 , wherein the polypeptide does not comprise more than one acidic amino acid residue within a region from amino acid 108 to amino acid 123 of the polypeptide.
10. The isolated polynucleotide of claim 1 , wherein the polypeptide comprises a domain from a replication protein selected from the group consisting of a phosphorylation domain; a DNA binding domain; a winged-helix domain; and combinations thereof.
11. A recombinant polynucleotide comprising a promoter sequence operably linked to the polynucleotide of claim 1 .
12. An isolated cell transformed with the recombinant polynucleotide of claim 11 .
13. A vector comprising the recombinant polynucleotide of claim 11 .