Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.1.32 (phosphoenolpyruvate carboxykinase)
 4,204 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expression of the phosphoenolpyruvate carboxylase (PEPC) gene involved in C4 photosynthesis is regulated in a highly organized manner. Nuclear factors interacting with DNA fragments from the 5' flanking region (from positions -1012 to +88 relative to the transcription start site) of the maize gene were identified by gel shift assays. Among the three kinds of such nuclear proteins (MNF1, MNF2a and MNF2b) found in the extract from maize leaves, MNF2a and MNF2b, which were distinguishable by their chromatographic behavior, interacted with the same motif of the repeated sequence (RS2) in the region from -432 to -201. MNF1 interacted with the region from -905 to -818 in which two copies of another kind of repeated sequence (RS1) reside. All of these nuclear factors were found only in the extracts from green and etiolated leaves but not in those from stems and roots. The relative content of MNF1 and MNF2b was almost equal in green and etiolated leaves, while that of MNF2a was significantly higher in etiolated leaves than green leaves. It is suggested that expression of the PEPC gene is controlled by the combined effects of these nuclear factors.
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PMID:Multiple interactions between tissue-specific nuclear proteins and the promoter of the phosphoenolpyruvate carboxylase gene for C4 photosynthesis in Zea mays. 226 39

MNF1 is a factor which specifically binds to a 318 bp fragment (-1012 to -695) in the 5'-flanking region of the C4-type phosphoenolpyruvate carboxylase gene in Zea mays (Yanagisawa et al., Mol Gen Genet 224 (1990) 325-332). The most preferred binding site of MNF1 determined by a 2 bp mutation-scanning assay was an octamer sequence, GTGCCCTT, which is located within the repeated sequences (RS1; -886 to -849, -846 to -807). Furthermore, a PCR-mediated selection-amplification assay identified both the octamer sequence, GTGCCC(A/T)(A/T), and an additional sequence. CC(G/A)CCC, the latter of which was similar to the Sp1 sites in vertebrates. Specific binding of MNF1 to each of the supposed binding sites was confirmed with double-stranded monomers as probes. Considering native molecular mass of MNF1 (ca. 500 kDa), a protein complex is expected. In addition, MNF1 is anticipated to have two distinct DNA-binding proteins since the MNF1 binding to CCGCCC element was 1,10-phenanthroline-dependent whereas the MNF1 binding to the octamer was independent. Wide distribution of the MNF1 binding sequences within the 1 kb promoter region accounts for broad interactions of MNF1. Moreover, specific DNA binding due to MNF1, which was not observed in the nuclear extract derived from germinated and cultivated plants in darkness, appeared after a white-light pulse. This finding suggests the involvement of the protein complex in the light-dependent transcriptional control in the gene expression.
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PMID:Identification of preferred binding sites of a light-inducible DNA-binding factor (MNF1) within 5'-upstream sequence of C4-type phosphoenolpyruvate carboxylase gene in maize. 974 8