title: Gene networks and chromatin and transcriptional regulation of the phaseolin promoter in Arabidopsis.
abstract: The complete lack of seed storage protein expression in vegetative tissues and robust expression during embryogenesis makes seed development an ideal system to study tissue-specific expression of genes. The promoter for the Phaseolin (phas) gene, which encodes the major seed storage protein in bean (Phaseolus vulgaris), is activated in two sequential steps: Phaseolus vulgaris ABI3-like factor (Pv-ALF)-dependent potentiation and abscisic acid-mediated activation. In this study, a heterologous in vivo Pv-ALF/phas-GUS (for β-glucuronidase) expression system in transgenic Arabidopsis thaliana leaves was used in conjunction with the powerful RNA-Seq approach to capture transcriptional landscapes of phas promoter expression. Remarkably, expression of over 1300 genes from 11 functional categories coincided with changes in the transcriptional status of the phas promoter. Gene network analysis of induced genes and artificial microRNA-mediated loss-of-function genetic assays identified transcriptional regulators RINGLET 2 (RLT2) and AINTEGUMENTA-LIKE 5 (AIL5) as being essential for phas transcription. Pv-ALF binding to the RLT2 and AIL5 promoter regions was confirmed by electrophoretic mobility shift assay. RLT2 and AIL5 knockdown lines displayed reduced expression of several endogenous seed genes, suggesting that these factors are involved in activation of endogenous Arabidopsis seed storage gene expression. Overall, the identification of these key factors involved in phas activation provides important insight into the two-step transcriptional regulation of seed-specific gene expression.
authors.affiliation: Institute of Developmental and Molecular Biology and Department of Biology, Texas A&M University, College Station, TX 77843-3155, USA.
authors.forename: Sabarinath
authors.initials: S
authors.lastname: Sundaram
authors.forename: Sunee
authors.initials: S
authors.lastname: Kertbundit
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Shakirov
authors.forename: Lakshminarayan M
authors.initials: LM
authors.lastname: Iyer
authors.forename: Miloslav
authors.initials: M
authors.lastname: Jurícek
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Hall
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002843:Chromatin / Q000235:genetics* / Q000378:metabolism; D016000:Cluster Analysis; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D055785:Gene Knockdown Techniques; D053263:Gene Regulatory Networks; D035683:MicroRNAs / Q000235:genetics; D008957:Models, Genetic; D020411:Oligonucleotide Array Sequence Analysis; D010937:Plant Growth Regulators / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011485:Protein Binding; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000235:genetics / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D059467:Transcriptome / Q000187:drug effects
chemical_list: D029681:Arabidopsis Proteins; D002843:Chromatin; D035683:MicroRNAs; D010937:Plant Growth Regulators; D010940:Plant Proteins; C096083:PvAlf protein, Phaseolus vulgaris; D015534:Trans-Activators; C048826:phaseolin protein, Phaseolus vulgaris; D000040:Abscisic Acid