Activation and memory of the heat shock response is mediated by prion-like domains of sensory HSFs in Arabidopsis.

Plants are able to sense and remember heat stress. An initial priming heat stress enables plants to acclimate so that they are able to survive a subsequent higher temperature. The heat shock transcription factors (HSFs) play a crucial role in this process, but the mechanisms by which plants sense heat stress are not well understood.

Monitoring Real-Time Temperature Dynamics of a Short RNA Hairpin Using Förster Resonance Energy Transfer and Circular Dichroism.

RNA molecules play crucial roles in gene expression regulation and cellular signaling, and these functions are governed by the formation of RNA secondary and tertiary structures. These structures are highly dynamic and subject to rapid changes in response to environmental cues, temperature in particular. Thermosensitive RNA secondary structures have been harnessed by multiple organisms to survey their temperature environment and to adjust gene expression accordingly.

In Vitro Determination of Temperature-Dependent DNA Binding of the Evening Complex Using Electrophoretic Mobility Shift Assays.

Electrophoretic mobility shift assays (EMSAs) of DNA-binding proteins and labeled DNA allow the qualitative and quantitative characterization of protein-DNA complex formation using native (nondenaturing) polyacrylamide or agarose gel electrophoresis. By varying the incubation temperature of the protein-DNA binding reaction and maintaining this temperature during electrophoresis, temperature-dependent protein-DNA interactions can be investigated. Here, we provide examples of the binding of a transcriptional repressor complex called the Evening Complex, comprising the DNA-binding protein LUX ARRYTHMO (LUX), the scaffold protein EARLY FLOWERING 3 (ELF3), and the adapter protein ELF4, to its cognate DNA and demonstrate direct detection and visualization of thermoresponsive binding in vitro.

Analysis of Phase Separation of EARLY FLOWERING 3.

Phase separation is an important mechanism for regulating various cellular functions. The EARLY FLOWERING 3 (ELF3) protein, an essential element of the EVENING COMPLEX (EC) involved in circadian clock regulation, has been shown to undergo phase separation. ELF3 is known to significantly influence elongation growth and flowering time regulation, and this is postulated to be due to whether the protein is in the dilute or phase-separated state.

Phytochromes transmit photoperiod information via the evening complex in Brachypodium.

Background: Daylength is a key seasonal cue for animals and plants. In cereals, photoperiodic responses are a major adaptive trait, and alleles of clock genes such as PHOTOPERIOD1 (PPD1) and EARLY FLOWERING3 (ELF3) have been selected for in adapting barley and wheat to northern latitudes. How monocot plants sense photoperiod and integrate this information into growth and development is not well understood.

Characterizing Different Modes of Interplay Between Rap1 and H3 Using Inducible H3-depletion Yeast.

Histones and transcription factors (TFs) are two important DNA-binding proteins that interact, compete, and together regulate transcriptional processes in response to diverse internal and external stimuli. Condition-specific depletion of histones in Saccharomyces cerevisiae using a galactose-inducible H3 promoter provides a suitable framework for examining transcriptional alteration resulting from reduced nucleosome content. However, the effect on DNA binding activities of TFs is yet to be fully explored.

25 Years of thermomorphogenesis research: milestones and perspectives.

In 1998, Bill Gray and colleagues showed that warm temperatures trigger arabidopsis hypocotyl elongation in an auxin-dependent manner. This laid the foundation for a vibrant research discipline. With several active members of the 'thermomorphogenesis' community, we here reflect on 25 years of elevated ambient temperature research and look to the future.

Phase separation and molecular ordering of the prion-like domain of the Arabidopsis thermosensory protein EARLY FLOWERING 3.

Liquid-liquid phase separation (LLPS) is an important mechanism enabling the dynamic compartmentalization of macromolecules, including complex polymers such as proteins and nucleic acids, and occurs as a function of the physicochemical environment. In the model plant, , LLPS by the protein EARLY FLOWERING3 (ELF3) occurs in a temperature-sensitive manner and controls thermoresponsive growth. ELF3 contains a largely unstructured prion-like domain (PrLD) that acts as a driver of LLPS in vivo and in vitro.

Temperature Sensing in Plants.

Temperature is a key environmental cue that influences the distribution and behavior of plants globally. Understanding how plants sense temperature and integrate this information into their development is important to determine how plants adapt to climate change and to apply this knowledge to the breeding of climate-resilient crops. The mechanisms of temperature perception in eukaryotes are only just beginning to be understood, with multiple molecular phenomena with inherent temperature dependencies, such as RNA melting, phytochrome dark reversion, and protein phase change, being exploited by nature to create thermosensory signaling networks.

Burning questions for a warming and changing world: 15 unknowns in plant abiotic stress.

We present unresolved questions in plant abiotic stress biology as posed by 15 research groups with expertise spanning eco-physiology to cell and molecular biology. Common themes of these questions include the need to better understand how plants detect water availability, temperature, salinity, and rising carbon dioxide (CO2) levels; how environmental signals interface with endogenous signaling and development (e.g.

The evening complex integrates photoperiod signals to control flowering in rice.

Plants use photoperiodism to activate flowering in response to a particular daylength. In rice, flowering is accelerated in short-day conditions, and even a brief exposure to light during the dark period (night-break) is sufficient to delay flowering. Although many of the genes involved in controlling flowering in rice have been uncovered, how the long- and short-day flowering pathways are integrated, and the mechanism of photoperiod perception is not understood.

PHYTOCHROME-INTERACTING FACTORS: a promising tool to improve crop productivity.

Light is a key determinant for plant growth, development, and ultimately yield. Phytochromes, red/far-red photoreceptors, play an important role in plant architecture, stress tolerance, and productivity. In the model plant Arabidopsis, it has been shown that PHYTOCHROME-INTERACTING FACTORS (PIFs; bHLH transcription factors) act as central hubs in the integration of external stimuli to regulate plant development.

Warm Temperature Promotes Shoot Regeneration in Arabidopsis thaliana.

Many plants are able to regenerate upon cutting, and this process can be enhanced in vitro by incubating explants on hormone-supplemented media. While such protocols have been used for decades, little is known about the molecular details of how incubation conditions influence their efficiency. In this study, we find that warm temperature promotes both callus formation and shoot regeneration in Arabidopsis thaliana.

Exploring contribution to early flowering in plants under daily variable temperature and its tissue-specific flowering gene network.

Molecular mechanisms of how constant temperatures affect flowering time have been largely characterized in the model plant ; however, the effect of natural daily variable temperature outside laboratories is only partly explored. Several flowering genes have been shown to play important roles in temperature responses, including () and (), the two genes encoding for the transcription factors (TFs) that act antagonistically to regulate flowering time by activating and repressing floral integrator (), respectively. In this study, we have taken a multidisciplinary approach to explore the contribution of to the early flowering observed in the daily variable temperature (VAR) and to broaden its transcriptional network using publicly available transcriptomic data.

An early-morning gene network controlled by phytochromes and cryptochromes regulates photomorphogenesis pathways in Arabidopsis.

Light perception at dawn plays a key role in coordinating multiple molecular processes and in entraining the plant circadian clock. The Arabidopsis mutant lacking the main photoreceptors, however, still shows clock entrainment, indicating that the integration of light into the morning transcriptome is not well understood. In this study, we performed a high-resolution RNA-sequencing time-series experiment, sampling every 2 min beginning at dawn.

Fine tuning of hormonal signaling is linked to dormancy status in sweet cherry flower buds.

In temperate trees, optimal timing and quality of flowering directly depend on adequate winter dormancy progression, regulated by a combination of chilling and warm temperatures. Physiological, genetic and functional genomic studies have shown that hormones play a key role in bud dormancy establishment, maintenance and release. We combined physiological and transcriptional analyses, quantification of abscisic acid (ABA) and gibberellins (GAs), and modeling to further investigate how these signaling pathways are associated with dormancy progression in the flower buds of two sweet cherry cultivars.

A prion-like domain in ELF3 functions as a thermosensor in Arabidopsis.

Temperature controls plant growth and development, and climate change has already altered the phenology of wild plants and crops. However, the mechanisms by which plants sense temperature are not well understood. The evening complex is a major signalling hub and a core component of the plant circadian clock.

An RNA thermoswitch regulates daytime growth in Arabidopsis.

Temperature is a major environmental cue affecting plant growth and development. Plants often experience higher temperatures in the context of a 24 h day-night cycle, with temperatures peaking in the middle of the day. Here, we find that the transcript encoding the bHLH transcription factor PIF7 undergoes a direct increase in translation in response to warmer temperature.

AT-Hook Transcription Factors Restrict Petiole Growth by Antagonizing PIFs.

Upon detecting abiotic or biotic stress, plants generally reduce their growth, enabling resources to be conserved and diverted to stress response mechanisms. In Arabidopsis thaliana, the AT-hook motif nuclear-localized (AHL) transcription factor family has been implicated in restricting rosette growth in response to stress. However, the mechanism by which AHLs repress growth in rosettes is unknown.

Molecular mechanisms of Evening Complex activity in .

The Evening Complex (EC), composed of the DNA binding protein LUX ARRHYTHMO (LUX) and two additional proteins EARLY FLOWERING 3 (ELF3) and ELF4, is a transcriptional repressor complex and a core component of the plant circadian clock. In addition to maintaining oscillations in clock gene expression, the EC also participates in temperature and light entrainment, acting as an important environmental sensor and conveying this information to growth and developmental pathways. However, the molecular basis for EC DNA binding specificity and temperature-dependent activity were not known.

From bud formation to flowering: transcriptomic state defines the cherry developmental phases of sweet cherry bud dormancy.

Background: Bud dormancy is a crucial stage in perennial trees and allows survival over winter to ensure optimal flowering and fruit production. Recent work highlighted physiological and molecular events occurring during bud dormancy in trees. However, they usually examined bud development or bud dormancy in isolation.

The Evening Complex Establishes Repressive Chromatin Domains Via H2A.Z Deposition.

The Evening Complex (EC) is a core component of the Arabidopsis () circadian clock, which represses target gene expression at the end of the day and integrates temperature information to coordinate environmental and endogenous signals. Here we show that the EC induces repressive chromatin structure to regulate the evening transcriptome. The EC component ELF3 directly interacts with a protein from the SWI2/SNF2-RELATED (SWR1) complex to control deposition of H2A.

Compartmentalized Synthesis of Triacylglycerol at the Inner Nuclear Membrane Regulates Nuclear Organization.

Cells dynamically adjust organelle organization in response to growth and environmental cues. This requires regulation of synthesis of phospholipids, the building blocks of organelle membranes, or remodeling of their fatty-acyl (FA) composition. FAs are also the main components of triacyglycerols (TGs), which enable energy storage in lipid droplets.

LHY2 Integrates Night-Length Information to Determine Timing of Poplar Photoperiodic Growth.

Day length is a key indicator of seasonal information that determines major patterns of behavior in plants and animals. Photoperiodism has been described in plants for about 100 years, but the underlying molecular mechanisms of day length perception and signal transduction in many systems are not well understood. In trees, photoperiod perception plays a major role in growth cessation during the autumn as well as activating the resumption of shoot growth in the spring, both processes controlled by FLOWERING LOCUS T2 (FT2) expression levels and critical for the survival of perennial plants over winter [1-4].