Combinatorial Transcriptional Control of Plant Specialized Metabolism

An increasing number of publications highlight the importance of cell type-specific stress responses that seem to be predominantly controlled at the transcriptional level. This may also be the case for JA-mediated defense mechanisms, but which components of combinatorial control of gene expression are involved in this is unclear. The number of described interactions of TFs of the same or different families is rising. An increasing number of tools has become available, facilitating the research on nonmodel plants such as next-generation sequencing, genome editing, and the isolation of populations of specific cell types. Past research in the field of regulation of specialized metabolism has focused on the discovery of TFs regulating specific metabolic pathway genes. The ensuing findings provide an excellent starting point to unravel how different TFs act in a coordinated manner and how DNA-related mechanisms have an impact on gene expression in specialized metabolism. Plants produce countless specialized compounds of diverse chemical nature and biological activities. Their biosynthesis often exclusively occurs either in response to environmental stresses or is limited to dedicated anatomical structures. In both scenarios, regulation of biosynthesis appears to be mainly controlled at the transcriptional level, which is generally dependent on a combined interplay of DNA-related mechanisms and the activity of transcription factors that may act in a combinatorial manner. How environmental and developmental cues are integrated into a coordinated cell type-specific stress response has only partially been unraveled so far. Building on the available examples from (metabolic) gene expression, here we propose theoretical models of how this integration of signals may occur at the level of transcriptional control. Plants produce countless specialized compounds of diverse chemical nature and biological activities. Their biosynthesis often exclusively occurs either in response to environmental stresses or is limited to dedicated anatomical structures. In both scenarios, regulation of biosynthesis appears to be mainly controlled at the transcriptional level, which is generally dependent on a combined interplay of DNA-related mechanisms and the activity of transcription factors that may act in a combinatorial manner. How environmental and developmental cues are integrated into a coordinated cell type-specific stress response has only partially been unraveled so far. Building on the available examples from (metabolic) gene expression, here we propose theoretical models of how this integration of signals may occur at the level of transcriptional control. a short DNA sequence in the regulatory region such as the promoter of a gene, to which a TF binds. a regulatory DNA element that modulates the expression of a target gene by recruiting TFs. Enhancer sequences may be located several megabases away from the transcriptional start site, but may be physically close by forming enhancer–promoter loops. multicellular specialized forms of trichomes that facilitate the release of specialized metabolites to the environment. plant cells that are morphologically and functionally different from the surrounding cells and often occur as single cells serving for specialized metabolite biosynthesis and/or storage. an oxylipin-type hormone that is classically regarded as a signaling molecule for herbivore attacks and necrotrophic pathogens but that also has important roles in plant growth and development. The active form of JA is the conjugate JA-isoleucine. morphologically distinct secretory plant cells storing latex that may be of diverse chemical nature depending on the species. traditionally defined as the compendium of pathways that produce often taxa-specific compounds not directly aiding plant growth and development but serving for interaction with the environment. This metabolism is also called secondary metabolism, as opposed to the ubiquitous primary metabolism, which is indispensable for growth and development. a protein that binds to DNA and thereby controls the transcription of a target gene.