Project description:The Arabidopsis thaliana REPRESSOR OF GA gene (RGA) encodes a DELLA protein that associates with multiple transcription factors to control plant growth in response to the hormone gibberellin (GA) (1). As part of a screen for genes that mediate the function of RGA in stem growth and shoot meristem function, we performed ChIP-seq to identify genome-wide loci associated with RGA in inflorescence apices. To detect genes controlled by RGA in a gain-of-function semi-dwarf background, we used a GFP-tagged, gibberellin-insensitive version of RGA (RGAp:GFP-rga-delta17) (2). (1) J.-M. Daviere, P. Achard, Gibberellin signaling in plants. Development 140, 1147-1151 (2013). (2) A. Dill, T. P. Sun, Synergistic derepression of gibberellin signaling by removing RGA and GAI function in Arabidopsis thaliana. Genetics 159, 777-785 (2001).
Project description:DELLA proteins act as hubs that relay environmental information to the multiple transcriptional circuits that control growth and development through physical interaction with transcription factors from different families. We have analyzed the presence of one DELLA protein at the Arabidopsis genome by chromatin immunoprecipitation coupled to large-scale sequencing and we find that it binds at the promoters of multiple genes. Enrichment analysis shows a strong preference for cis elements recognized by specific transcription factor families. In particular, we demonstrate that DELLA proteins are recruited by type-B ARABIDOPSIS RESPONSE REGULATORS (ARR) to the promoters of cytokinin-regulated genes, where they act as transcriptional co-activators. The biological relevance of this mechanism is underpinned by the necessity of simultaneous presence of DELLAs and ARRs to restrict root meristem growth and to promote photomorphogenesis. Provided are 3 biological replicates analysing RGA binding sites in Arabidopsis seedlings. ChIP-seq was performed on plants expressing RGA-GFP under the native RGA promoter and on non-transgenic control plants as reference
Project description:The Arabidopsis thaliana REPLUMLESS gene (RPL), also known as PENNYWISE (PNY) and BELLRINGER (BLR) encodes a BEL1-like TALE homeodomain (BLH) transcription factor that controls multiple aspects of meristem and floral development, including meristem maintenance, phyllotaxis, transition to flowering, stem development and floral organ patterning [1-3]. As part of a screen for genes that mediate the function of RPL in the processes above, we performed ChIP-seq to identify genome-wide RPL binding sites within inflorescence apices. 1. Byrne, M.E., Groover, A.T., Fontana, J.R., and Martienssen, R.A. (2003). Development 130, 3941-3950. 2. Roeder, A.H.K., Ferrandiz, C., and Yanofsky, M.F. (2003). Current Biology 13, 1630-1635. 3. Smith, H.M.S., and Hake, S. (2003). Plant Cell 15, 1717-1727.