title: A specific variant of the PHR1 binding site is highly enriched in the Arabidopsis phosphate-responsive phospholipase DZ2 coexpression network.
abstract: PLDZ2 is a member of the Arabidopsis phospholipase D gene family that is induced in both shoot and root in response to phosphate (Pi) starvation. Recently, through deletion and gain-of-function analyses of the PLDZ2 promoter, we identified a 65 bp region (denominated enhancer EZ2) capable of conferring tissue-specific and low-Pi responses to a minimal inactive promoter. The EZ2 element contains two P1BS motifs, each of which is the binding site for PHR1 and related transcription factors. This structural organization is evolutionarily conserved in orthologous promoters within the rosid clade. To determine whether EZ2 is significantly over-represented in Arabidopsis genes coexpressed with PLDZ2, we constructed a PLDZ2 coexpression network containing 26 genes, almost half of them encoding enzymes or regulatory proteins involved in Pi recycling. A variant of the P1BS motif was found to be highly enriched in the promoter regions of these coexpressed genes, showing an EZ2-like arrangement in seven of them. No other motifs were significantly enriched. The over-representation of the EZ2 arrangement of P1BS motifs in the promoters of genes coexpressed with PLDZ2, suggests this unit has a particularly important role as a regulatory element in a coexpression network involved in the release of Pi from phospholipids and other molecules under Pi-limiting conditions.
authors: Centro Universitario de la Ciénega, Universidad de Guadalajara (CUCI-UdeG), Ocotlan, Jalisco, Mexico.
authors: Gustavo
authors: G
authors: Acevedo-Hernández
authors: Araceli
authors: A
authors: Oropeza-Aburto
authors: Luis
authors: L
authors: Herrera-Estrella
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D053263:Gene Regulatory Networks / Q000187:drug effects*; D017343:Genes, Plant / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D010710:Phosphates / Q000494:pharmacology*; D010739:Phospholipase D / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding / Q000187:drug effects / Q000235:genetics; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C514695:PHR1 protein, Arabidopsis; D010710:Phosphates; D014157:Transcription Factors; D010739:Phospholipase D; C510354:phospholipase Dzeta2, Arabidopsis