PBF-2 is a novel single-stranded DNA binding factor implicated in PR-10a gene activation in potato.
Elicitor-induced activation of the potato pathogenesis-related gene PR-10a requires a 30-bp promoter sequence termed the ERE (elicitor response element) that is bound by the nuclear factor PBF-2 (PR-10a binding factor 2). In this study, PBF-2 has been purified to near homogeneity from elicited tubers through a combination of anion-exchange and DNA affinity chromatography. Evidence demonstrates that inactive PBF-2 is stored in the nuclei of fresh tubers and becomes available for binding to the ERE upon elicitation. A protein with an apparent molecular mass of 24 kD (p24) is a DNA binding component of PBF-2. A cDNA encoding p24 has been cloned and encodes a novel protein with a potential transcriptional activation domain that could also act as a single-stranded DNA binding domain. Both PBF-2 and the cDNA-encoded protein bind with high affinity to the single-stranded form of the ERE in a sequence-specific manner. The inverted repeat sequence of the ERE, TGACAnnnnTGTCA, is critical for binding of this factor in vitro and for PR-10a expression in vivo, supporting the role of PBF-2 as a transcriptional regulator.
Desveaux
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D
Department of Biochemistry, Université de Montréal, Montréal, Québec, Canada H3C 3J7.
Després
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C
Joyeux
A
A
Subramaniam
R
R
Brisson
N
N
D000595:Amino Acid Sequence; D000906:Antibodies / Q000276:immunology / Q000494:pharmacology; D001483:Base Sequence; D001665:Binding Sites; D002467:Cell Nucleus / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D004277:DNA, Single-Stranded / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics*; D017930:Genes, Reporter / Q000235:genetics; D008957:Models, Genetic; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009154:Mutation; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000235:genetics; D010937:Plant Growth Regulators / Q000494:pharmacology; D010940:Plant Proteins; D011485:Protein Binding / Q000187:drug effects; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D020218:Response Elements / Q000235:genetics; D011198:Solanum tuberosum / Q000166:cytology / Q000187:drug effects / Q000235:genetics*; D013379:Substrate Specificity; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D015533:Transcriptional Activation / Q000187:drug effects
D000906:Antibodies; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C416516:PBF-2 protein, Solanum tuberosum; D010455:Peptides; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011994:Recombinant Proteins; D015534:Trans-Activators; C097188:polyglutamine