Search tips
Search criteria 


Logo of molcellbPermissionsJournals.ASM.orgJournalMCB ArticleJournal InfoAuthorsReviewers
Mol Cell Biol. 1992 December; 12(12): 5673–5682.
PMCID: PMC360507

Sequence of cDNA comprising the human pur gene and sequence-specific single-stranded-DNA-binding properties of the encoded protein.


The human Pur factor binds strongly to a sequence element repeated within zones of initiation of DNA replication in several eukaryotic cells. The protein binds preferentially to the purine-rich single strand of this element, PUR. We report here the cloning and sequencing of a cDNA encoding a protein with strong affinity for the PUR element. Analysis with a series of mutated oligonucleotides defines a minimal single-stranded DNA Pur-binding element. The expressed Pur open reading frame encodes a protein of 322 amino acids. This protein, Pur alpha, contains three repeats of a consensus motif of 23 amino acids and two repeats of a second consensus motif of 26 amino acids. Near its carboxy terminus, the protein possesses an amphipathic alpha-helix and a glutamine-rich domain. The repeat region of Pur cDNA is homologous to multiple mRNA species in each of several human cell lines and tissues. The HeLa cDNA library also includes a clone encoding a related gene, Pur beta, containing a version of the 23-amino-acid consensus motif similar, but not identical, to those in Pur alpha. Results indicate a novel type of modular protein with capacity to bind repeated elements in single-stranded DNA.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (2.1M), or click on a page image below to browse page by page.

Images in this article

Click on the image to see a larger version.

Articles from Molecular and Cellular Biology are provided here courtesy of American Society for Microbiology (ASM)