The founder-cell transcriptome in the Arabidopsis apetala1 cauliflower inflorescence meristem. (December 2016)

• Record Type: Journal Article
• Authors: Frerichs, Anneke; Thoma, Rahere; Abdallah, Ali; Frommolt, Peter; Werr, Wolfgang; Chandler, John
• Is Part Of: BMC genomics. Volume 17:Number 1(2016)
• Page Start: 1
• Page End: 18
• Publication Date: 2016-12
• Subjects: apetala1 cauliflower -- Bract -- DORNRÖSCHEN-LIKE -- Fluorescence-activated cell sorting -- Inflorescence meristem -- Lateral organ founder cell -- RNA-seq -- Transcriptome; Genomes -- Periodicals; Gene mapping -- Periodicals; Genomics -- Periodicals; Base Sequence -- Periodicals; Chromosome Mapping -- Periodicals; Genetic Techniques -- Periodicals; Sequence Analysis, DNA -- Periodicals; 572.8605
• DOI: 10.1186/s12864-016-3189-x
• Languages: English
• ISSNs: 1471-2164

Abstract

Abstract Background Although the pattern of lateral organ formation from apical meristems establishes species-specific plant architecture, the positional information that confers cell fate to cells as they transit to the meristem flanks where they differentiate, remains largely unknown. We have combined fluorescence-activated cell sorting and RNA-seq to characterise the cell-type-specific transcriptome at the earliest developmental time-point of lateral organ formation usingDORNRÖSCHEN-LIKE::GFP to mark founder-cell populations at the periphery of the inflorescence meristem (IM) inapetala1 cauliflower double mutants, which overproliferate IMs. Results Within the lateral organ founder-cell population at the inflorescence meristem, floral primordium identity genes are upregulated and stem-cell identity markers are downregulated. Additional differentially expressed transcripts are involved in polarity generation and boundary formation, and in epigenetic and post-translational changes. However, only subtle transcriptional reprogramming within the global auxin network was observed. Conclusions The transcriptional network of differentially expressed genes supports the hypothesis that lateral organ founder-cell specification involves the creation of polarity from the centre to the periphery of the IM and the establishment of a boundary from surrounding cells, consistent with bract initiation. However, contrary to the established paradigm that sites of auxin response maxima pre-pattern lateral organ initiation in the IM, auxin response might play a minor role in the earliest stages of lateral floral initiation.