Thermal-Tactile Integration in Object Temperature Perception

In plants, environmental conditions such as temperature affect survival, growth, and fitness, particularly during key stages such as seedling growth and reproduction. To survive and thrive in changing conditions, plants have evolved adaptive responses that tightly regulate developmental processes such as hypocotyl elongation and flowering time in response to environmental temperature changes. Increases in temperature, coupled with increasing fluctuations in local climate and weather, severely affect our agricultural systems; therefore, understanding the mechanisms by which plants perceive and respond to temperature is critical for agricultural sustainability. In this review, we summarize recent findings on the molecular mechanisms of ambient temperature perception as well as possible temperature sensing components in plants. Based on recent publications, we highlight several temperature response mechanisms, including the deposition and eviction of histone variants, DNA methylation, alternative splicing, protein degradation, and protein localization. We discuss roles of each proposed temperature-sensing mechanism that affects plant development, with an emphasis on flowering time. Studies of plant ambient temperature responses are advancing rapidly, and this review provides insights for future research aimed at understanding the mechanisms of temperature perception and responses in plants.

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Capturing the dynamics of peripersonal space by integrating sound propagation properties and expectancy effects

10.1101/756783 ◽

2019 ◽

Author(s):

Lise Hobeika ◽

Marine Taffou ◽

Thibaut Carpentier ◽

Olivier Warusfel ◽

Isabelle Viaud-Delmon

Keyword(s):

Sound Propagation ◽

Current Method ◽

Peripersonal Space ◽

The Body ◽

Logarithmic Scale ◽

List Type ◽

Expectancy Effects ◽

Near Space ◽

Propagation Properties ◽

Tactile Integration

AbstractHighlightsLogarithmically distributed auditory distances provides an apt granularity of PPSMeasuring expectation helps to interpret behavioral impact of audiotactile integrationTactile RTs follows a logarithmic decrease due to audiotactile integrationPeripersonal space is better characterized and quantified with this refinementBackgroundHumans perceive near space and far space differently. Peripersonal space, i.e. the space directly surrounding the body, is often studied using paradigms based on auditory-tactile integration. In these paradigms, reaction time to a tactile stimulus is measured in the presence of a concurrent auditory looming stimulus.New MethodWe propose here to refine the experimental procedure considering sound propagation properties in order to improve granularity and relevance of auditory-tactile integration measures. We used a logarithmic distribution of distances for this purpose. We also want to disentangle behavioral contributions of the targeted audiotactile integration mechanisms from expectancy effects. To this aim, we added to the protocol a baseline with a fixed sound distance.ResultsExpectation contributed significantly to overall behavioral responses. Subtracting it isolated the audiotactile effect due to the stimulus proximity. This revealed that audiotactile integration effects have to be tested on a logarithmic scale of distances, and that they follow a linear variation on this scale.Comparison with Existing Method(s)The granularity of the current method is more relevant, providing higher spatial resolution in the vicinity of the body. Furthermore, most of the existing methods propose a sigmoid fitting, which rests on the intuitive framework that PPS is an in-or-out zone. Our results suggest that behavioral effects follow a logarithmic decrease, thus a response graduated in space.ConclusionsThe proposed protocol design and method of analysis contribute to refine the experimental investigation of the factors influencing and modifying multisensory integration phenomena in the space surrounding the body.

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PHYTOCHROMES B1/B2 ARE KEY REGULATORS OF EPIGENOME REPROGRAMMING DURING TOMATO FRUIT DEVELOPMENT

10.1101/2020.07.30.227447 ◽

2020 ◽

Author(s):

Ricardo Bianchetti ◽

Nicolas Bellora ◽

Luis A de Haro ◽

Rafael Zuccarelli ◽

Daniele Rosado ◽

...

Keyword(s):

Fruit Development ◽

Epigenetic Modification ◽

Tomato Fruit ◽

Dna Demethylation ◽

Temperature Perception ◽

Genome Wide ◽

Fruit Development And Ripening ◽

Histone Modifying Enzymes ◽

Level Of Understanding ◽

Agronomical Traits

AbstractPhytochrome-mediated light and temperature perception has been shown to be a major regulator of fruit development. Furthermore, chromatin remodelling via DNA demethylation has been described as a crucial mechanism behind the fruit ripening process; however, the molecular basis underlying the triggering of this epigenetic modification remains largely unknown. Here, an integrative analyses of the methylome, siRNAome and transcriptome of tomato fruits from phyA and phyB1B2 null mutants was performed, revealing that PHYB1 and PHYB2 influences genome-wide DNA methylation during fruit development and ripening. The experimental evidence indicates that PHYB1B2 signal transduction relies on a gene expression network that includes chromatin organization factors (DNA methylases/demethylases, histone-modifying enzymes and remodelling factors) and transcriptional regulators, ultimately leading to altered mRNA profile of photosynthetic and ripening-associated genes. This new level of understanding provides insights into the orchestration of epigenetic mechanisms in response to environmental cues affecting agronomical traits in fleshy fruits.

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