Characterization of the single-strand-specific BPV-1 origin binding protein, SPSF I, as the HeLa Pur alpha factor.
SPSF I and II are two cellular proteins which bind specifically to single-stranded DNA. SPSF I and II binding sites are found in the minimal origin of replication of BPV-1 DNA and near the P2 promoter of the cellular c-myc gene. DNA-binding properties of the two proteins to single-stranded oligonucleotides of different lengths and sequences were quantified by determination of DNA-binding constants. The binding constant of SPSF proteins to the lower strand of the BPV-1 origin was determined to be 1.5 x 10(-10) M-1. Peptide sequences derived from purified SPSF I and II revealed the identity of at least one of the SPSF proteins with the so-called HeLa Pur alpha factor. The HeLa Pur alpha factor was identified previously by virtue of its capacity to bind to purine-rich strands of the PUR element found in initiation zones of DNA replication [Bergemann, A.D., Ma,Z.-W. and Johnson, E.M. (1992) Mol. Cell. Biol. 12, 5673-5682]. Expression of the Pur cDNA confirmed the identity of the Pur alpha protein with the 42 kDa SPSF I protein. Analysis of several Pur alpha cDNA clones revealed the existence of an extended 3'-untranslated region in all Pur mRNAs.
Jurk
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Institut für Biochemie, Ludwig-Maximilians-Universität München, Germany.
Weissinger
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F
Lottspeich
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F
Schwarz
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U
Winnacker
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EL
D000818:Animals; D001483:Base Sequence; D052688:Bovine papillomavirus 1 / Q000235:genetics* / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein; D004277:DNA, Single-Stranded / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D018741:Replication Origin; D018411:Spodoptera / Q000166:cytology; D013950:Thymus Gland / Q000378:metabolism; D014157:Transcription Factors
D017362:Cyclic AMP Response Element-Binding Protein; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; C501130:PURA protein, human; D012333:RNA, Messenger; D011994:Recombinant Proteins; D014157:Transcription Factors