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Determinism and contingency shape evolutionary trajectories and the extent to which evolution is predictable depends on the relative contribution of each. However, the causes of predictable evolution are poorly understood. Here we take advantage of the fact that gene family recruitment may be more deterministic, and therefore predictable, when functional evolution is constrained to fewer genetic solutions. At the same time, the number of genes in a family capable of a specific function may be contingent on the vagaries of gene duplication mutations, functional changes, and maintenance, and therefore more difficult to predict. Here we analyze sulfotransferases using phylogenetics, gene expression, recombinant protein expression, and in vitro functional analyses. Sulfotransferases are the only enzymes known to catalyze sulfation, acting across a broad range of substrates and taxa, predicting that biological sulfation is catalyzed by sulfotransferases. We examine the bioluminescence system of ostracods and synthesize our findings with those reported previously for fireflies and sea pansies to show one aspect of bioluminescence, substrate metabolism, evolved convergently, each time recruiting sulfotransferase genes. However, our findings suggest that unlike fireflies, which have one known sulfotransferase gene specialized for substrate metabolism, ostracods contain several highly expressed sulfotransferase genes biochemically capable of metabolizing their bioluminescent substrate. While gene family recruitment may be predictable when limited genetic solutions exist, the number and specific identity of genes encoding a biological function may be difficult to predict because of the stochastic nature of gene duplication mutations and the diversity of mechanisms that fix and functionally differentiate these genes.

The ability to trace every cell in some model organisms has led to the fundamental understanding of development and cellular function. However, in plants the complexity of cell number, organ size, and developmental time makes this a challenge even in the diminutive model plant Arabidopsis (Arabidopsis thaliana). Duckweed, basal nongrass aquatic monocots, provide an opportunity to follow every cell of an entire plant due to their small size, reduced body plan, and fast clonal growth habit. Here we present a chromosome-resolved genome for the highly invasive Lesser Duckweed (Lemna minuta) and generate a preliminary cell atlas leveraging low cell coverage single-nuclei sequencing. We resolved the 360 megabase genome into 21 chromosomes, revealing a core nonredundant gene set with only the ancient tau whole-genome duplication shared with all monocots, and paralog expansion as a result of tandem duplications related to phytoremediation. Leveraging SMARTseq2 single-nuclei sequencing, which provided higher gene coverage yet lower cell count, we profiled 269 nuclei covering 36.9% (8,457) of the L. minuta transcriptome. Since molecular validation was not possible in this nonmodel plant, we leveraged gene orthology with model organism single-cell expression datasets, gene ontology, and cell trajectory analysis to define putative cell types. We found that the tissue that we computationally defined as mesophyll expressed high levels of elemental transport genes consistent with this tissue playing a role in L. minuta wastewater detoxification. The L. minuta genome and preliminary cell map provide a paradigm to decipher developmental genes and pathways for an entire plant.

Fluorescent proteins based on light, oxygen, and voltage (LOV) sensing photoreceptors are among the few reporter gene technologies available for studying living systems in oxygen-free environments that render reporters based on the green fluorescent protein nonfluorescent. LOV reporters develop fluorescence by binding flavin mononucleotide (FMN), which they endogenously obtain from cells. As FMN is essential to cell physiology as well as for determining fluorescence in LOV proteins, it is important to be able to study and characterize flavin binding in LOV reporters. To this end, we report a method for reversibly separating FMN from two commonly used LOV reporters to prepare stable and soluble apoproteins. Using fluorescence titration, we measured the equilibrium dissociation constant for binding with all three cellular flavins: FMN, flavin adenine dinucleotide, and riboflavin. Finally, we exploit the riboflavin affinity of apo LOV reporters, identified in this work, to develop a fluorescence turn-on biosensor for vitamin B2.

Abstract The current study explores the role of narrative content and non-diegetic music, as well as their interplay in the creation of film suspense. In a between-subjects design, three audience groups watched either the full version (audio–video) of a suspenseful short movie (Love Field) or a video-only version or listened to the audio track only. Audience responses were assessed with a combination of continuous response measurement (CRM) and psychophysiological measures, comprising heart rate (i.e., inter-beat interval, IBI), pulse volume amplitude (PVA), and skin conductance level (SCL). Frame-by-frame content coding was performed to identify distinct plot segments and musical moods (tense vs. relaxing) and mark the critical visual and auditory events that directed the audience’s inferences about the nature of the plot and elicited specific outcome expectations. Results showed that continuous self-report data and objective physiological measures were largely dissociated, suggesting different processing modalities. Tense music alone induced feelings of suspense (CRM) even in the absence of any clues about the story content. Overall, the audio-only version led to the highest arousal levels, as indicated by SCL and PVA, while the video-only version led to the lowest arousal levels. IBI data revealed short-term heart rate deceleration responses to salient narrative clues that could be interpreted in terms of heightened attention and cognitive resource allocation. Results are discussed in light of a multidimensional framework of tension and suspense and a terminological differentiation of both concepts.

Fluorescence imaging represents cornerstone technology for studying biological function at the cellular and molecular levels. The technology's centerpiece is a prolific collection of genetic reporters based on the green fluorescent protein (GFP) and related analogs. More than two decades of protein engineering have endowed the GFP repertoire with an incredible assortment of fluorescent proteins, allowing scientists immense latitude in choosing reporters tailored to various cellular and environmental contexts. Nevertheless, GFP and derivative reporters have specific limitations that hinder their unrestricted use for molecular imaging. These challenges have inspired the development of new reporter proteins and imaging mechanisms. Here, we review how these developments are expanding the frontiers of reporter gene techniques to enable nondestructive studies of cell function in anaerobic environments and deep inside intact animals-two important biological contexts that are fundamentally incompatible with the use of GFP-based reporters.

Inferring emotions from others’ non-verbal behavior is a pervasive and fundamental task in social interactions. Typically, real-life encounters imply the co-location of interactants, i.e., their embodiment within a shared spatial-temporal continuum in which the trajectories of the interaction partner’s Expressive Body Movement (EBM) create mutual social affordances. Shared Virtual Environments (SVEs) and Virtual Characters (VCs) are increasingly used to study social perception, allowing to reconcile experimental stimulus control with ecological validity. However, it remains unclear whether display modalities that enable co-presence have an impact on observers responses to VCs’ expressive behaviors. Drawing upon ecological approaches to social perception, we reasoned that sharing the space with a VC should amplify affordances as compared to a screen display, and consequently alter observers’ perceptions of EBM in terms of judgment certainty, hit rates, perceived expressive qualities (arousal and valence), and resulting approach and avoidance tendencies. In a between-subject design, we compared the perception of 54 10-s animations of VCs performing three daily activities (painting, mopping, sanding) in three emotional states (angry, happy, sad)—either displayed in 3D as a co-located VC moving in shared space, or as a 2D replay on a screen that was also placed in the SVEs. Results confirm the effective experimental control of the variable of interest, showing that perceived co-presence was significantly affected by the display modality, while perceived realism and immersion showed no difference. Spatial presence and social presence showed marginal effects. Results suggest that the display modality had a minimal effect on emotion perception. A weak effect was found for the expression “happy,” for which unbiased hit rates were higher in the 3D condition. Importantly, low hit rates were observed for all three emotion categories. However, observers judgments significantly correlated for category assignment and across all rating dimensions, indicating universal decoding principles. While category assignment was erroneous, though, ratings of valence and arousal were consistent with expectations derived from emotion theory. The study demonstrates the value of animated VCs in emotion perception studies and raises new questions regarding the validity of category-based emotion recognition measures.

Despite extensive characterization of crassulacean acid metabolism (CAM) in terrestrial angiosperms, little attention has been given to aquatics and early diverging land plants. Here, the authors assemble the genome of Isoetes taiwanensis and investigate the genetic factors driving CAM in this aquatic lycophyte.

Sudden cardiac death (SCD) in patients with heart failure (HF) is allied with an imbalance in reduction and oxidation (redox) signaling in cardiomyocytes; however, the basic pathways and mechanisms governing redox homeostasis in cardiomyocytes are not fully understood. Here, we show that cytochrome b5 reductase 3 (CYB5R3), an enzyme known to regulate redox signaling in erythrocytes and vascular cells, is essential for cardiomyocyte function. Using a conditional cardiomyocyte-specific CYB5R3-knockout mouse, we discovered that deletion of CYB5R3 in male, but not female, adult cardiomyocytes causes cardiac hypertrophy, bradycardia, and SCD. The increase in SCD in CYB5R3-KO mice is associated with calcium mishandling, ventricular fibrillation, and cardiomyocyte hypertrophy. Molecular studies reveal that CYB5R3-KO hearts display decreased adenosine triphosphate (ATP), increased oxidative stress, suppressed coenzyme Q levels, and hemoprotein dysregulation. Finally, from a translational perspective, we reveal that the high-frequency missense genetic variant rs1800457, which translates into a CYB5R3 T117S partial loss-of-function protein, associates with decreased event-free survival (~20%) in Black persons with HF with reduced ejection fraction (HFrEF). Together, these studies reveal a crucial role for CYB5R3 in cardiomyocyte redox biology and identify a genetic biomarker for persons of African ancestry that may potentially increase the risk of death from HFrEF.

Sudden cardiac death (SCD) in patients with heart failure (HF) is allied with an imbalance in reduction and oxidation (redox) signaling in cardiomyocytes; however, the basic pathways and mechanisms governing redox homeostasis in cardiomyocytes are not fully understood. Here, we show that cytochrome b5 reductase 3 (CYB5R3), an enzyme known to regulate redox signaling in erythrocytes and vascular cells, is essential for cardiomyocyte function. Using a conditional cardiomyocytespecific CYB5R3-knockout mouse, we discovered that deletion of CYB5R3 in male, but not female, adult cardiomyocytes causes cardiac hypertrophy, bradycardia, and SCD. The increase in SCD in CYB5R3-KO mice is associated with calcium mishandling, ventricular fibrillation, and cardiomyocyte hypertrophy. Molecular studies reveal that CYB5R3-KO hearts display decreased adenosine triphosphate (ATP), increased oxidative stress, suppressed coenzyme Q levels, and hemoprotein dysregulation. Finally, from a translational perspective, we reveal that the high-frequency missense genetic variant rs1800457, which translates into a CYB5R3 T117S partial loss-of-function protein, associates with decreased event-free survival (~20%) in Black persons with HF with reduced ejection fraction (HFrEF). Together, these studies reveal a crucial role for CYB5R3 in cardiomyocyte redox biology and identify a genetic biomarker for persons of African ancestry that may potentially increase the risk of death from HFrEF., Introduction The healthy heart requires a highly synchronized series of reduction and oxidation (redox) reactions to support the electrical and mechanical demands of beating cardiomyocytes (1). In the aging population, [...]

Public speaking engages and entertains audiences. Through neuroimaging, we can examine responses to speeches in real time. Replicating an earlier study, this study carries out two kinds of analyses – forward and reverse correlations. First, we examine how the soundwave carrying the speech relates to brain responses, finding that bilateral auditory cortex responses track with the speech signal's energy. Second, we use the speech-evoked brain responses to reverse-identify salient moments in the speech. Specifically, we focus on the right temporoparietal junction (TPJ), a region associated with social cognition. We find that TPJ-peaks reverse-identify socially engaging content (defined by the ability to evoke laughter). These results demonstrate new ways to study the relationship between story content and the audience responses it evokes. [ABSTRACT FROM AUTHOR]

Cranberry (Vaccinium macrocarpon) is a member of the Heath family (Ericaceae) and is a temperate low-growing woody perennial native to North America that is both economically important and has significant health benefits. While some native varieties are still grown today, breeding programs over the past 50 years have made significant contributions to improving disease resistance, fruit quality and yield. An initial genome sequence of an inbred line of the wild selection ‘Ben Lear,’ which is parent to multiple breeding programs, provided insight into the gene repertoire as well as a platform for molecular breeding. Recent breeding efforts have focused on leveraging the circumboreal V. oxycoccos, which forms interspecific hybrids with V. macrocarpon, offering to bring in novel fruit chemistry and other desirable traits. Here we present an updated, chromosome-resolved V. macrocarpon reference genome, and compare it to a high-quality draft genome of V. oxycoccos. Leveraging the chromosome resolved cranberry reference genome, we confirmed that the Ericaceae has undergone two whole genome duplications that are shared with blueberry and rhododendron. Leveraging resequencing data for ‘Ben Lear’ inbred lines, as well as several wild and elite selections, we identified common regions that are targets of improvement. These same syntenic regions in V. oxycoccos, were identified and represent environmental response and plant architecture genes. These data provide insight into early genomic selection in the domestication of a native North American berry crop.

A detailed damage survey of the El Reno, Oklahoma, tornado of 31 May 2013 combined with rapid-scanning data recorded from two mobile radars is presented. One of the radars was equipped with polarimetric capability. The relationship between several suction vortices visually identified in pictures with the high-resolution Doppler velocity data and swath marks in fields is discussed. The suction vortices were associated with small shear features in Doppler velocity and a partial ringlike feature of high spectral width. For the first time, a suction vortex that created a swath mark in a field was visually identified in photographs and high-definition video while the rotational couplet was tracked by radar. A dual-Doppler wind synthesis of the tornadic circulation at low levels near the location of several storm chaser fatalities resolved ground-relative wind speeds in excess of 90 m s−1, greater than the minimum speed for EF5 damage. The vertical vorticity analysis revealed a rapid transition from a single tornadic vortex centered on the weak-echo hole (WEH) to suction vortices surrounding the WEH and collocated with the ring of enhanced radar reflectivities. Several bands/zones of enhanced convergence were resolved in the wind syntheses. One of the bands was associated with an internal or secondary rear-flank gust front. An inner band of convergence appeared to be a result of the positive bias in tornado-relative radial velocity owing to centrifuging of large lofted debris swirling within the tornado. An outer band of convergence formed at the northern edge of a region of strong inflow that was lofting small debris and dust into the storm.

Abstract This study presents rapid-scanning X-band polarimetric radar data combined with photogrammetry of the El Reno tornado of 31 May 2013. The relationship between the hook echo, weak-echo hole (WEH), weak-echo column (WEC), and the rotational couplet with the visual characteristics of the tornado are shown. For the first time, cross-correlation coefficient (ρhv) and differential reflectivity (ZDR) data are included in the photogrammetric analyses. The tornado was accompanied by a large tornadic debris signature (TDS) with a diameter ~2 km wide during the analysis time. The center of the TDS was not collocated with the WEH and the rotational couplet. Instead, the TDS was displaced ~1 km to the north and within the weak-echo notch of the hook echo. A “debris overhang” was identified in vertical cross sections of the ρhv fields. The overhang was located in a weak-echo trench and a notch of high ρhv, consistent with the position of the tornado updraft. The updraft was hypothesized to be carrying small debris particles to heights that produced the overhang signature. A U-shaped band of high ρhv and ZDR was resolved in a vertical cross section and positioned at the periphery of the WEC during one of the analysis times. It was proposed that the band formed as a result of hydrometeors encircling the WEC while being surrounded on all sides by relatively hydrometeor-free air. The characteristics of the scatterers within the WEC were resolved and believed to be composed of a low concentration of very small, randomly oriented, debris particles, even in the presence of strong centrifuging, and a general absence of hydrometeors.