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Angenent, G. C.

Publications and source records attributed to Angenent, G. C..

2 recordsLinked to original sources

A gene regulatory network critical for axillary bud dormancy directly controlled by Arabidopsis BRANCHED1

The control of branch outgrowth is critical for plant fitness, stress resilience and crop yield. The Arabidopsis thaliana transcription factor BRANCHED1 (BRC1) plays a pivotal role in this process as it integrates signals that inhibit axillary bud growth to control shoot branching. Despite the remarkable activity of BRC1 as a potent growth inhibitor, the mechanisms by which it promotes and maintains bud dormancy are still largely unknown. Here we combine ChIP-seq, transcriptomic and systems biology approaches to characterise the BRC1-regulated gene network. We identify a group of BRC1 direct target genes encoding transcription factors (BTFs) that orchestrate, together with BRC1, an intricate transcriptional network enriched in abscisic acid signalling components. The BRC1 network is enriched in feed-forward loops and feed-back loops, robust against noise and mutation, reversible in response to stimuli, and stable once established. This knowledge is fundamental to adapt plant architecture and crop production to ever-changing environmental conditions.

plant biology

FRUITFULL-like genes regulate flowering time and inflorescence architecture in tomato

The timing of flowering and inflorescence architecture are critical for the reproductive success of tomato, but the gene regulatory networks underlying these traits have not been fully explored. Here we show that the tomato FRUITFULL-like (FUL-like) genes FUL2 and MADS-BOX PROTEIN 20 (MBP20) induce flowering and repress inflorescence branching by promoting floral meristem determinacy. FUL1 fulfils a less prominent role and appears to depend on FUL2 and MBP20 for its upregulation in the inflorescence- and floral meristems. MBP10, the fourth tomato FUL-like gene, has probably lost its function. The tomato FUL-like proteins cannot homodimerize in in vitro assays, but heterodimerize with various other MADS-domain proteins, potentially forming distinct complexes in the transition meristem and floral meristem. Transcriptome analysis of the primary shoot meristems revealed various interesting downstream targets, including four repressors of cytokinin signalling that are upregulated during the vegetative-to-reproductive transition in ful1 ful2 mbp10 mbp20 mutants. FUL2 and MBP20 can also bind in vitro to the upstream regions of these genes, thereby probably directly stimulating cell division in the meristem upon the transition to flowering. The control of inflorescence branching does not occur via the CKXs, but appears regulated by repression of transcription factors such as TM3, APETALA 2b (AP2b) and AP2a.

plant biology