Transcriptomic landscape ofseedstickinArabidopsis thalianafuniculus after fertilisation

Abstract

AbstractIn Angiosperms, the continuation of plant species is intricately dependent on the funiculus multifaceted role in nutrient transport, mechanical support, and dehiscence of seeds. SEEDSTICK (STK) is a MADS-box transcription factor involved in seed size and dehiscence, and one of the few genes identified as affecting funiculus growth. Given the importance of the funiculus to a correct seed development, allied with previous phenotypic observations ofstkmutants, we performed a transcriptomic analysis ofstkfuniculi, using RNA-sequencing, to infer on the deregulated networks of genes. The generated dataset of differentially expressed genes was enriched with cell wall biogenesis, cell cycle, sugar metabolism and transport terms, all in accordance withstkphenotype. We selected eight differentially expressed genes involved with abscission, seed development or novel functions instkfuniculus, such as hormones/secondary metabolites transport, for transcriptome validation using qPCR and/or promoter reporter lines. Overall, the analysis performed in this study allowed delving into the STK-network established in Arabidopsis funiculus, fulfilling a literature gap. Simultaneously, our findings reinforced the reliability of the transcriptome, and identified processes and new candidate genes that will enable a better understanding on the role of this sporophytic structure and how seed development may be affected by it.