PROTEIN ARGININE METHYLTRANSFERASES (PRMTs) catalyze arginine (R) methylation that is critical for transcriptional and post-transcriptional gene regulation. In Arabidopsis, PRMT5 that catalyzes symmetric R dimethylation is best characterized. PRMT5 mutants are late-flowering and show altered responses to environmental stress.
View Article and Find Full Text PDFAdolescents' late chronotypes colliding with early school start times (SSTs) are associated with students' unhealthy sleep habits. Most studies comparing different SSTs associate later SSTs with longer sleep duration and lower social jetlag. However, the magnitude of the effect varies between studies and the effect of different SSTs on chronotype is not well established.
View Article and Find Full Text PDFArabidopsis (Arabidopsis thaliana) PROTEIN ARGININE METHYLTRANSFERASE5 (PRMT5) post-translationally modifies RNA-binding proteins by arginine (R) methylation. However, the impact of this modification on the regulation of RNA processing is largely unknown. We used the spliceosome component, SM-LIKE PROTEIN 4 (LSM4), as a paradigm to study the role of R-methylation in RNA processing.
View Article and Find Full Text PDFThe impact of rising global temperatures on crop yields is a serious concern, and the development of heat-resistant crop varieties is crucial for mitigating the effects of climate change on agriculture. To achieve this, a better understanding of the molecular basis of the thermal responses of plants is necessary. The circadian clock plays a central role in modulating plant biology in synchrony with environmental changes, including temperature fluctuations.
View Article and Find Full Text PDFCircadian rhythms are entrained by external factors such as sunlight and social cues, but also depend on internal factors such as age. Adolescents exhibit late chronotypes, but worldwide school starts early in the morning leading to unhealthy sleep habits. Several studies reported that adolescents benefit from later school start times.
View Article and Find Full Text PDFSchools start early in the morning all over the world, contrasting with adolescents' late chronotype. Interestingly, lower academic performance (i.e.
View Article and Find Full Text PDFThe misalignment between late chronotypes and early school start times affect health, performance and psychological well-being of adolescents. Here we test whether, and how, the baseline chronotype (i.e.
View Article and Find Full Text PDFMusic is ubiquitous in our lives. Although we listen to music as an activity in and of itself, music is frequently played while we are engaged in other activities that rely on decision-making (e.g.
View Article and Find Full Text PDFRecent studies have shown a temporal increase in the neutralizing antibody potency and breadth to SARS-CoV-2 variants in coronavirus disease 2019 (COVID-19) convalescent individuals. Here, we examined longitudinal antibody responses and viral neutralizing capacity to the B.1 lineage virus (Wuhan related), to variants of concern (VOC; Alpha, Beta, Gamma, and Delta), and to a local variant of interest (VOI; Lambda) in volunteers receiving the Sputnik V vaccine in Argentina.
View Article and Find Full Text PDFMassive vaccination offers great promise for halting the global COVID-19 pandemic. However, the limited supply and uneven vaccine distribution create an urgent need to optimize vaccination strategies. We evaluate SARS-CoV-2-specific antibody responses after Sputnik V vaccination of healthcare workers in Argentina, measuring IgG anti-spike titers and neutralizing capacity after one and two doses in a cohort of naive or previously infected volunteers.
View Article and Find Full Text PDFMost living organisms possess an internal timekeeping mechanism known as the circadian clock, which enhances fitness by synchronizing the internal timing of biological processes with diurnal and seasonal environmental changes. In plants, the pace of these biological rhythms relies on oscillations in the expression level of hundreds of genes tightly controlled by a group of core clock regulators and co-regulators that engage in transcriptional and translational feedback loops. In the last decade, the role of several core clock genes in the control of defense responses has been addressed, and a growing amount of evidence demonstrates that circadian regulation is relevant for plant immunity.
View Article and Find Full Text PDFThe COVID-19 pandemic [1] resulted in many countries imposing a lockdown, which in turn reduces sunlight exposure and alters daily social schedules. Since these are the main entrainment factors for biological rhythms [2], we hypothesized that the lockdown may have affected sleep and circadian rhythms. We indeed show that participants slept longer and later during lockdown weekdays, and exhibited lower levels of social jetlag.
View Article and Find Full Text PDFThe circadian clock modulates immune responses in plants and animals; however, it is unclear how host-pathogen interactions affect the clock. Here we analyzed clock function in Arabidopsis thaliana mutants with defective immune responses and found that enhanced disease susceptibility 4 (eds4) displays alterations in several circadian rhythms. Mapping by sequencing revealed that EDS4 encodes the ortholog of NUCLEOPORIN 205, a core component of the inner ring of the nuclear pore complex (NPC).
View Article and Find Full Text PDFMost adolescents exhibit very late chronotypes and attend school early in the morning, a misalignment that can affect their health and psychological well-being. Here we examine how the interaction between the chronotype and school timing of an individual influences academic performance, studying a unique sample of 753 Argentinian students who were randomly assigned to start school in the morning (07:45), afternoon (12:40) or evening (17:20). Although chronotypes tend to align partially with class time, this effect is insufficient to fully account for the differences with school start time.
View Article and Find Full Text PDFBecause of their sessile nature, plants have adopted varied strategies for growing and reproducing in an ever-changing environment. Control of mRNA levels and pre-mRNA alternative splicing are key regulatory layers that contribute to adjust and synchronize plant growth and development with environmental changes. Transcription and alternative splicing are thought to be tightly linked and coordinated, at least in part, through a network of transcriptional and splicing regulatory factors that interact with the carboxyl-terminal domain (CTD) of the largest subunit of RNA polymerase II.
View Article and Find Full Text PDFLight signaling pathways interact with the circadian clock to help organisms synchronize physiological and developmental processes to periodic environmental cycles. The plant photoreceptors responsible for clock resetting have been characterized, but signaling components that link the photoreceptors to the clock remain to be identified. Members of the family of NIGHT LIGHT⁻INDUCIBLE AND CLOCK-REGULATED () genes play key roles linking light regulation of gene expression to the control of daily and seasonal rhythms in .
View Article and Find Full Text PDFThe circadian clock is an important endogenous timekeeper, helping plants to prepare for the periodic changes of light and darkness in their environment. The clockwork of this molecular timer is made up of clock proteins that regulate transcription of their own genes with a 24 h rhythm. Furthermore, the rhythmically expressed clock proteins regulate time-of-day dependent transcription of downstream genes, causing messenger RNA (mRNA) oscillations of a large part of the transcriptome.
View Article and Find Full Text PDFTime representation is a fundamental property of human cognition. Ample evidence shows that time (and numbers) are represented in space. However, how the conceptual mapping varies across individuals, scales, and temporal structures remains largely unknown.
View Article and Find Full Text PDFCurr Opin Plant Biol
February 2017
Circadian clocks are molecular devices that help adjust organisms to periodic environmental changes. Although formally described as self-sustaining oscillators that are synchronized by external cues and produce defined outputs, it is increasingly clear that physiological processes not only are regulated by, but also regulate the function of the clock. We discuss three recent examples of the intimate relationships between the function of the clock, growth and metabolism in photosynthetic organisms: the daily tracking of sun by sunflowers, the fine computations plants and cyanobacteria perform to manage carbon reserves and prevent starvation, and the changes in clock parameters that went along with domestication of tomato.
View Article and Find Full Text PDFHuman behavior and physiology exhibit diurnal fluctuations. These rhythms are entrained by light and social cues, with vast individual differences in the phase of entrainment - referred as an individual's chronotype - ranging in a continuum between early larks and late owls. Understanding whether decision-making in real-life situations depends on the relation between time of the day and an individual's diurnal preferences has both practical and theoretical implications.
View Article and Find Full Text PDFTheories of expertise based on the acquisition of chunk and templates suggest a differential geometric organization of perception between experts and novices. It is implied that expert representation is less anchored by spatial (Euclidean) proximity and may instead be dictated by the intrinsic relation in the structure and grammar of the specific domain of expertise. Here we set out to examine this hypothesis.
View Article and Find Full Text PDFThe immune and the circadian systems interact in a bidirectional fashion. The master circadian oscillator, located in the suprachiasmatic nuclei (SCN) of the hypothalamus, responds to peripheral and local immune stimuli, such as proinflammatory cytokines and bacterial endotoxin. Astrocytes exert several immune functions in the CNS, and there is growing evidence that points toward a role of these cells in the regulation of circadian rhythms.
View Article and Find Full Text PDFDuring a decision-making process, the body changes. These somatic changes have been related to specific cognitive events and also have been postulated to assist decision-making indexing possible outcomes of different options. We used chess to analyze heart rate (HR) modulations on specific cognitive events.
View Article and Find Full Text PDFMany immune parameters exhibit daily and circadian oscillations, including the number of circulating cells and levels of cytokines in the blood. Mice also have a differential susceptibility to lipopolysaccharide (LPS or endotoxin)-induced endotoxic shock, depending on the administration time in the 24 h light-dark (LD) cycle. We replicated these results in LD, but we did not find temporal differences in LPS-induced mortality in constant darkness (DD).
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