Distinct profiles of plant immune resilience revealed by natural variation in warm temperature-modulated disease resistance among Arabidopsis accessions.

Elevated temperature suppresses the plant defence hormone salicylic acid (SA) by downregulating the expression of master immune regulatory genes CALMODULIN BINDING PROTEIN 60-LIKE G (CBP60g) and SYSTEMIC ACQUIRED RESISTANCE DEFICIENT1 (SARD1). However, previous studies in Arabidopsis thaliana plants have primarily focused on the accession Columbia-0 (Col-0), while the genetic determinants of intraspecific variation in Arabidopsis immunity under elevated temperature remain unknown. Here we show that BASIC HELIX LOOP HELIX 059 (bHLH059), a thermosensitive SA regulator at nonstress temperatures, does not regulate immune suppression under warmer temperatures.

The plant disease triangle facing climate change: a molecular perspective.

Variations in climate conditions can dramatically affect plant health and the generation of climate-resilient crops is imperative to food security. In addition to directly affecting plants, it is predicted that more severe climate conditions will also result in greater biotic stresses. Recent studies have identified climate-sensitive molecular pathways that can result in plants being more susceptible to infection under unfavorable conditions.

Structural diversity and stress regulation of the plant immunity-associated CALMODULIN-BINDING PROTEIN 60 (CBP60) family of transcription factors in Solanum lycopersicum (tomato).

Cellular signaling generates calcium (Ca) ions, which are ubiquitous secondary messengers decoded by calcium-dependent protein kinases, calcineurins, calreticulin, calmodulins (CAMs), and CAM-binding proteins. Previous studies in the model plant Arabidopsis thaliana have shown the critical roles of the CAM-BINDING PROTEIN 60 (CBP60) protein family in plant growth, stress responses, and immunity. Certain CBP60 factors can regulate plant immune responses, like pattern-triggered immunity, effector-triggered immunity, and synthesis of major plant immune-activating metabolites salicylic acid (SA) and N-hydroxypipecolic acid (NHP).

Molecular regulation of the salicylic acid hormone pathway in plants under changing environmental conditions.

Salicylic acid (SA) is a central plant hormone mediating immunity, growth, and development. Recently, studies have highlighted the sensitivity of the SA pathway to changing climatic factors and the plant microbiome. Here we summarize organizing principles and themes in the regulation of SA biosynthesis, signaling, and metabolism by changing abiotic/biotic environments, focusing on molecular nodes governing SA pathway vulnerability or resilience.

Natural frequencies of two bubbles in a compliant tube: analytical, simulation, and experimental results.

Motivated by various clinical applications of ultrasound contrast agents within blood vessels, the natural frequencies of two bubbles in a compliant tube are studied analytically, numerically, and experimentally. A lumped parameter model for a five degree of freedom system was developed, accounting for the compliance of the tube and coupled response of the two bubbles. The results were compared to those produced by two different simulation methods: (1) an axisymmetric coupled boundary element and finite element code previously used to investigate the response of a single bubble in a compliant tube and (2) finite element models developed in comsol Multiphysics.

The effect of the cannabinoid-receptor antagonist, SR141716, on the early stage of kainate-induced epileptogenesis in the adult rat.

Pretreatment with the endocannabinoid-receptor antagonist, SR141716, has been reported to suppress the long-lasting hyperexcitability and increased seizure susceptibility present after 30 min of hyperthermia-induced convulsions in immature rats, an animal model of complex febrile seizures in children, which may be a cause of temporal lobe epilepsy. The present experiments tested the hypothesis that SR141716 suppresses epileptogenesis in the adult kainate model, an animal model of temporal lobe epilepsy. Adult male rats (n = 35), implanted for electroencephalography (EEG) recordings, were treated with kainate.

Chronic social stress and susceptibility to concentrated ambient fine particles in rats.

Background: Epidemiologic evidence suggests that chronic stress may alter susceptibility to air pollution. However, persistent spatial confounding between these exposures may limit the utility of epidemiologic methods to disentangle these effects and cannot identify physiologic mechanisms for potential differential susceptibilities.

Objectives: Using a rat model of social stress, we compared respiratory responses to fine concentrated ambient particles (CAPs) and examined biological markers of inflammation.

Identifying druglike inhibitors of myelin-reactive T cells by phenotypic high-throughput screening of a small-molecule library.

Inflammatory T cells that are reactive to myelin protein components of the CNS play a critical role in the pathogenesis of multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). The authors have previously generated mice that predominantly harbor T cells transgenic for a T-cell receptor (TCR) that is specific to the myelin proteolipid protein (PLP) 139-151 and that spontaneously develop MS-like paralysis. T cells from healthy transgenic mice respond to stimulation with PLP139-151 in a highly specific manner by proliferation and secretion of proinflammatory cytokines such as interleukin (IL)-2 and interferon (INF)-gamma in vitro.

Analysis of theta power in hippocampal EEG during bar pressing and running behavior in rats during distinct behavioral contexts.

These experiments examine changes in theta power as measured by wavelet analysis in five rats performing a conditional visual discrimination task and a simple running task. In the conditional task, rats were trained to press one lever to initiate a trial and then to press one of two choice levers, each corresponding to one of two cue lights. Analysis of theta power in this operant task found a large decrease in theta power during the choice bar presses, in contrast to the increase in theta power during trial initiation bar presses.

Stimulation in hippocampal region CA1 in behaving rats yields long-term potentiation when delivered to the peak of theta and long-term depression when delivered to the trough.

Experimental evidence suggests that the hippocampal theta rhythm plays a critical role in learning. Previous studies have shown long-term potentiation (LTP) to be preferentially induced with stimulation on the peak of local theta rhythm in region CA1 in anesthetized rats and with stimulation of the perforant path at the peak of theta in both anesthetized and behaving animals. We set out to determine the effects of tetanic burst stimulation in stratum radiatum of region CA1 in awake behaving animals, delivered during either the peak or the trough of the theta rhythm in the EEG.