Project description:This SuperSeries is composed of the following subset Series: GSE38358: Molecular basis for the specification of floral organs by APETALA3 and PISTILLATA (ChIP-Seq) GSE38362: Molecular basis for the specification of floral organs by APETALA3 and PISTILLATA (mRNA) Refer to individual Series
Project description:The gene expression profiles of inflorescences of the floral homeotic mutants apetala1, apetala2, apetala3, pistillata, and agamous were compared to wild-type inflorescences using a flower-specific cDNA array (GSM21001-21015) and a "whole-genome" oligonucleotide array (Operon) (GSM21016-21035). All experiments were performed at least in triplicate. This SuperSeries is composed of the SubSeries listed below.
Project description:Many flowering plants attract pollinators by offering a reward of floral nectar. Remarkably, the molecular events involved in the development of nectaries, the organs that produce nectar, as well as the synthesis and secretion of nectar itself, are poorly understood. Indeed, to date, no genes have been shown to directly affect the de novo production or quality of floral nectar. To address this gap in knowledge, the ATH1 Affymetrix GeneChip array was used to systematically investigate the Arabidopsis nectary transcriptome to identify genes and pathways potentially involved in nectar production. In this study, we identified a large number of genes differentially expressed between secretory lateral nectaries and non-secretory median nectary tissues, as well as between mature lateral nectaries (post-anthessis) and immature lateral nectary tissue (pre-anthesis).
Project description:Flower development is a dynamics process in which floral organs are produced from pools of stem cells residing in meristems (Smyth et al., 1990). In order to obtain a high resolution map of the changes of gene expression during this process thus to provide insights into specific expression patterns and their underlying gene regulatory networks, an inducible system which allows us to obtain synchronized flowers (Wellmer et al., 2006) was used to collect stage-specific floral tissues at four stages (stages 0, 2, 4 and 8) for transcriptome profiling by RNA-seq . These stages represent the status of inflorescence meristem, floral meristem specification, floral organ specification and floral organ differentiation, respectively during Arabidopsis flower development.
Project description:Plants have evolved a unique and conserved developmental program that enables the conversion of leaves into floral organs. Elegant genetic and molecular work has identified key regulators of floral meristem identity. However, further understanding of flower meristem specification has been hampered by redundancy and by pleiotropic effects. The KNOXI gene STM transcription factor is a well-characterized regulator of shoot apical meristem maintenance. stm loss-of-function mutants arrest shortly after germination, and therefore the knowledge on later roles of STM, including flower development, is limited. Here, we uncover a role for STM in the specification of flower meristem identity. Silencing STM in the AP1 expression domain in the ap1-4 mutant background resulted in a complete leafy-like flower phenotype and an intermediate stm-2 allele enhanced the floral meristem identity phenotype of ap1-4. Transcriptional profiling of STM perturbation suggested that STM activity affects multiple meristem identity and flower transition genes, among them the F-Box gene UFO. In agreement, stm-2 enhanced the ufo-2 floral meristem fate phenotype, and ectopic UFO expression rescued the leafy flowers in genetic backgrounds with compromised AP1 and STM activities. This work suggests a molecular mechanism that underlies the activity of STM in the specification of flower meristem identity.