An autoactive NB-LRR gene causes Rht13 dwarfism in wheat.

Semidwarfing genes have greatly increased wheat yields globally, yet the widely used gibberellin (GA)-insensitive genes Rht-B1b and Rht-D1b have disadvantages for seedling emergence. Use of the GA-sensitive semidwarfing gene Rht13 avoids this pleiotropic effect. Here, we show that Rht13 encodes a nucleotide-binding site/leucine-rich repeat (NB-LRR) gene. A point mutation in the semidwarf Rht-B13b allele autoactivates the NB-LRR gene and causes a height reduction comparable with Rht-B1b and Rht-D1b in diverse genetic backgrounds. The autoactive Rht-B13b allele leads to transcriptional up-regulation of pathogenesis-related genes including class III peroxidases associated with cell wall remodeling. Rht13 represents a new class of reduced height (Rht) gene, unlike other Rht genes, which encode components of the GA signaling or metabolic pathways. This discovery opens avenues to use autoactive NB-LRR genes as semidwarfing genes in a range of crop species, and to apply Rht13 in wheat breeding programs using a perfect genetic marker.

A conditional mutation in a wheat (Triticum aestivum L.) gene regulating root morphology.

KEY MESSAGE: Characterisation and genetic mapping of a key gene defining root morphology in bread wheat. Root morphology is central to plants for the efficient uptake up of soil water and mineral nutrients. Here we describe a conditional mutant of hexaploid wheat (Triticum aestivum L.) that when grown in soil with high Ca2+ develops a larger rhizosheath accompanied with shorter roots than the wild type. In wheat, rhizosheath size is a reliable surrogate for root hair length and this was verified in the mutant which possessed longer root hairs than the wild type when grown in high Ca2+ soil. We named the mutant Stumpy and showed it to be due to a single semi-dominant mutation. The short root phenotype at high Ca2+ was due to reduced cellular elongation which might also explain the long root hair phenotype. Analysis of root cell walls showed that the polysaccharide composition of Stumpy roots is remodelled when grown at non-permissive (high) Ca2+ concentrations. The mutation mapped to chromosome 7B and sequencing of the 7B chromosomes in both wild type and Stumpy identified a candidate gene underlying the Stumpy mutation. As part of the process to determine whether the candidate gene was causative, we identified wheat lines in a Cadenza TILLING population with large rhizosheaths but accompanied with normal root length. This finding illustrates the potential of manipulating the gene to disconnect root length from root hair length as a means of developing wheat lines with improved efficiency of nutrient and water uptake. The Stumpy mutant will be valuable for understanding the mechanisms that regulate root morphology in wheat.

Reappraising reappraisal: an expanded view.

Reappraisal is a frequently used and often successful emotion regulation strategy. However, its underlying cognitive mechanisms are not well understood. In this paper, we seek to clarify these mechanisms by expanding upon our recently proposed reAppraisal framework. According to this framework, reappraisal consists of appraisal shifts that arise from changes to the mental construal of a situation (reconstrual) or from changes to the goals that are used to evaluate the construal (repurposing). Here we propose that reappraisal can target both object-level construals and goals representing states in the environment as well as meta-level construals and goals about different states in the mind. We also propose that reappraisal can operate by facilitating decommitment from a dominant construal or goal as well as by facilitating commitment to alternative construals or goals. We demonstrate that the 2 × 2 × 2 matrix formed by crossing the three distinctions between reconstrual and repurposing, between object-level and meta-level representations, and between decommitment and commitment operations forms a useful map of different reappraisal tactics. We draw examples of each of the 8 reappraisal tactics from basic and clinical research. We conclude by considering future research inspired by the expanded reAppraisal framework.

Cultural differences in caring for people with dementia: a pilot study of concern about losing face and loneliness in Chinese American and European American caregivers.

OBJECTIVES: Heavy demands upon dementia caregivers can lead to a number of poor health outcomes including declines in physical, mental, and brain health. Although dementia affects people from all backgrounds, research in the US has largely focused on European American caregivers. This has made providing culturally-competent care more difficult. This study begins to address this issue by empirically examining how culturally-shaped beliefs can influence loneliness in family caregivers of people with dementia. METHODS: We conducted a preliminary questionnaire study with Chinese American and European American family caregivers of people with dementia (N = 72). RESULTS: Chinese American caregivers were more concerned than European American caregivers about losing face, which in turn, was associated with greater loneliness. This pattern remained when accounting for caregiver gender, age, and relationship to the person with dementia. CONCLUSIONS: These preliminary findings highlight the role that cultural beliefs can play in adverse caregiver outcomes, and suggest that addressing concerns about losing face may be an important way for healthcare providers to help reduce loneliness among Chinese American caregivers. CLINICAL IMPLICATIONS: Understanding how cultural beliefs influence caregiver outcomes is critical as healthcare professionals work to provide culturally-competent care and design culturally-sensitive interventions.

The Health Behavior Model of Personality in the Context of a Public Health Crisis.

OBJECTIVE: The US Centers for Disease Control and Prevention recommended behavioral measures to slow the spread of COVID-19, such as social distancing and wearing masks. Although many individuals comply with these recommendations, compliance has been far from universal. Identifying predictors of compliance is crucial for improving health behavior messaging and thereby reducing disease spread and fatalities. METHODS: We report preregistered analyses from a longitudinal study that investigated personality predictors of compliance with behavioral recommendations in diverse US adults across five waves from March to August 2020 (n = 596) and cross-sectionally in August 2020 (n = 405). RESULTS: Agreeableness-characterized by compassion-was the most consistent predictor of compliance, above and beyond other traits, and sociodemographic predictors (sample A, ß = 0.25; sample B, ß = 0.12). The effect of agreeableness was robust across two diverse samples and sensitivity analyses. In addition, openness, conscientiousness, and extraversion were also associated with greater compliance, but effects were less consistent across sensitivity analyses and were smaller in sample A. CONCLUSIONS: Individuals who are less agreeable are at higher risk for noncompliance with behavioral mandates, suggesting that health messaging can be meaningfully improved with approaches that address these individuals in particular. These findings highlight the strong theoretical and practical utility of testing long-standing psychological theories during real-world crises.

Coping With Health Threats: The Costs and Benefits of Managing Emotions.

How people respond to health threats can influence their own health and, when people are facing communal risks, even their community's health. We propose that people commonly respond to health threats by managing their emotions with cognitive strategies such as reappraisal, which can reduce fear and protect mental health. However, because fear can also motivate health behaviors, reducing fear may also jeopardize health behaviors. In two diverse U.S. samples (N = 1,241) tracked across 3 months, sequential and cross-lagged panel mediation models indicated that reappraisal predicted lower fear about an ongoing health threat (COVID-19) and, in turn, better mental health but fewer recommended physical health behaviors. This trade-off was not inevitable, however: The use of reappraisal to increase socially oriented positive emotions predicted better mental health without jeopardizing physical health behaviors. Examining the costs and benefits of how people cope with health threats is essential for promoting better health outcomes for individuals and communities.

Overgrowth mutants determine the causal role of gibberellin GA2oxidaseA13 in Rht12 dwarfism of wheat.

The induced dwarf mutant Rht12 was previously shown to have agronomic potential to replace the conventional DELLA mutants Rht-B1b/Rht-D1b in wheat. The Rht12 dwarfing gene is not associated with reduced coleoptile length (unlike the DELLA mutants) and it is dominant, characteristics which are shared with the previously characterized dwarfing genes Rht18 and Rht14. Using the Rht18/Rht14 model, a gibberellin (GA) 2-oxidase gene was identified in the Rht12 region on chromosome 5A. A screen for suppressor mutants in the Rht12 background identified tall overgrowth individuals that were shown to contain loss-of-function mutations in GA2oxidaseA13, demonstrating the role of this gene in the Rht12 dwarf phenotype. It was concluded that Rht12, Rht18, and Rht14 share the same height-reducing mechanism through the increased expression of GA 2-oxidase genes. Some of the overgrowth mutants generated in this study were semi-dwarf and taller than the original Rht12 dwarf, providing breeders with new sources of agronomically useful dwarfism.

Poor caregiver mental health predicts mortality of patients with neurodegenerative disease.

Dementia and other neurodegenerative diseases cause profound declines in functioning; thus, many patients require caregivers for assistance with daily living. Patients differ greatly in how long they live after disease onset, with the nature and severity of the disease playing an important role. Caregiving can also be extremely stressful, and many caregivers experience declines in mental health. In this study, we investigated the role that caregiver mental health plays in patient mortality. In 176 patient-caregiver dyads, we found that worse caregiver mental health predicted greater patient mortality even when accounting for key risk factors in patients (i.e., diagnosis, age, sex, dementia severity, and patient mental health). These findings highlight the importance of caring for caregivers as well as patients when attempting to improve patients' lives.

Genotyping on the ark: A synthesis of genetic resources available for species in zoos.

Using molecular genetic information to guide population management can improve the sustainability of species in captivity. However, empirical population genetics has not been commonly applied to species management programs in zoos. One limitation may be the availability of genetic resources (e.g., markers, primers, etc.) for species held in zoos. To assess the extent to which species held in zoos have been studied using population genetics in the wild, we conducted a systematic literature review of close to 8,000 papers. We synthesized information on the availability and scale of population genetics studies across amphibian, bird, mammal, and reptile species held in zoos, and discussed their potential for informing ex situ management. We found that more than half of the species in zoos (52%) already have some genetic markers described in the literature specific for them, or a congeneric species, that could be further developed to aid the management of zoo populations, and the accumulation of these resources has been steady over the past decades. Furthermore, the proportion of species with genetic resources is even higher (62%) for species that are being managed through a formal breeding program in zoos. Our study provides encouraging results for captive program managers interested in integrating population genetics into ex situ management strategies.

Increase in coleoptile length and establishment by Lcol-A1, a genetic locus with major effect in wheat.

BACKGROUND: Good establishment is important for rapid leaf area development in wheat crops. Poor establishment results in fewer, later-emerging plants, reduced leaf area and tiller number. In addition, poorly established crops suffer from increased soil moisture loss through evaporation and greater competition from weeds while fewer spikes are produced which can reduce grain yield. By protecting the emerging first leaf, the coleoptile is critical for achieving good establishment, and its length and interaction with soil physical properties determine the ability of a cultivar to emerge from depth. RESULTS: Here we characterise a locus on chromosome 1AS, that increases coleoptile length in wheat, which we designate as Lcol-A1. We identified Lcol-A1 by bulked-segregant analysis and used a Halberd-derived population to fine map the gene to a 2 cM region, equivalent to 7 Mb on the IWGSC genome reference sequence of Chinese Spring (RefSeqv1.0). By sowing recently released cultivars and near-isogenic lines in the field at both conventional and deep sowing depths, we confirmed that Locl-A1 was associated with increased emergence from depth in the presence and absence of conventional dwarfing genes. Flanking markers IWB58229 and IWA710 were developed to assist breeders to select for long coleoptile wheats. CONCLUSIONS: Increased coleoptile length is sought in many global wheat production areas to improve crop emergence. The identification of the gene Lcol-A1, together with tools to allow wheat breeders to track the gene, will enable improvements to be made for this important trait.

Rht18 Semidwarfism in Wheat Is Due to Increased GA 2-oxidaseA9 Expression and Reduced GA Content.

Semidwarfing genes have improved crop yield by reducing height, improving lodging resistance, and allowing plants to allocate more assimilates to grain growth. In wheat (Triticum aestivum), the Rht18 semidwarfing gene was identified and deployed in durum wheat before it was transferred into bread wheat, where it was shown to have agronomic potential. Rht18, a dominant and gibberellin (GA) responsive mutant, is genetically and functionally distinct from the widely used GA-insensitive semidwarfing genes Rht-B1b and Rht-D1b In this study, the Rht18 gene was identified by mutagenizing the semidwarf durum cultivar Icaro (Rht18) and generating mutants with a range of tall phenotypes. Isolating and sequencing chromosome 6A of these "overgrowth" mutants showed that they contained independent mutations in the coding region of GA2oxA9GA2oxA9 is predicted to encode a GA 2-oxidase that metabolizes GA biosynthetic intermediates into inactive products, effectively reducing the amount of bioactive GA (GA1). Functional analysis of the GA2oxA9 protein demonstrated that GA2oxA9 converts the intermediate GA12 to the inactive metabolite GA110 Furthermore, Rht18 showed higher expression of GA2oxA9 and lower GA content compared with its tall parent. These data indicate that the increased expression of GA2oxA9 in Rht18 results in a reduction of both bioactive GA content and plant height. This study describes a height-reducing mechanism that can generate new genetic diversity for semidwarfism in wheat by combining increased expression with mutations of specific amino acid residues in GA2oxA9.

Two Endosomal NHX-Type Na+/H+ Antiporters are Involved in Auxin-Mediated Development in Arabidopsis thaliana.

In Arabidopsis thaliana, the endosomal-localized Na+/H+ antiporters NHX5 and NHX6 regulate ion and pH homeostasis and are important for plant growth and development. However, the mechanism by which these endosomal NHXs function in plant development is not well understood. Auxin modulates plant growth and development through the formation of concentration gradients in plant tissue to control cell division and expansion. Here, we identified a role for NHX5 and NHX6 in the establishment and maintenance of auxin gradients in embryo and root tissues. We observed developmental impairment and abnormal cell division in embryo and root tissues in the double knockout nhx5 nhx6, consistent with these tissues showing high expression of NHX5 and NHX6. Through confocal microscopy imaging with the DR5::GFP auxin reporter, we identify defects in the perception, accumulation and redistribution of auxin in nhx5 nhx6 cells. Furthermore, we find that the steady-state levels of the PIN-FORMED (PIN) auxin efflux carriers PIN1 and PIN2 are reduced in nhx5 nhx6 root cells. Our results demonstrate that NHX5 and NHX6 function in auxin-mediated plant development by maintaining PIN abundance at the plasma membrane, and provide new insight into the regulation of plant development by endosomal NHX antiporters.

Zebularine treatment is associated with deletion of FT-B1 leading to an increase in spikelet number in bread wheat.

The number of rachis nodes (spikelets) on a wheat spike is a component of grain yield that correlates with flowering time. The genetic basis regulating flowering in cereals is well understood, but there are reports that flowering time can be modified at a high frequency by selective breeding, suggesting that it may be regulated by both epigenetic and genetic mechanisms. We investigated the role of DNA methylation in regulating spikelet number and flowering time by treating a semi-spring wheat with the demethylating agent, Zebularine. Three lines with a heritable increase in spikelet number were identified. The molecular basis for increased spikelet number was not determined in 2 lines, but the phenotype showed non-Mendelian inheritance, suggesting that it could have an epigenetic basis. In the remaining line, the increased spikelet phenotype behaved as a Mendelian recessive trait and late flowering was associated with a deletion encompassing the floral promoter, FT-B1. Deletion of FT-B1 delayed the transition to reproductive growth, extended the duration of spike development, and increased spikelet number under different temperature regimes and photoperiod. Transiently disrupting DNA methylation can generate novel flowering behaviour in wheat, but these changes may not be sufficiently stable for use in breeding programs.

Cardiac Vagal Control and Depressive Symptoms: The Moderating Role of Sleep Quality.

Lower cardiac vagal control (CVC) has been linked to greater depression. However, this link has not been consistently demonstrated, suggesting the presence of key moderators. Sleep plausibly is one such factor. Therefore, we investigated whether sleep quality moderates the link between CVC (quantified by high-frequency heart rate variability, HF-HRV) and depressive symptoms (assessed using established questionnaires) in 29 healthy women. Results revealed a significant interaction between HF-HRV and sleep quality in predicting depressive symptoms: participants with lower HF-HRV reported elevated depressive symptoms only when sleep quality was also low. In contrast, HF-HRV was not associated with depressive symptoms when sleep quality was high, suggesting a protective function of high sleep quality in the context of lower CVC.

Barley (Hordeum vulgare) circadian clock genes can respond rapidly to temperature in an EARLY FLOWERING 3-dependent manner.

An increase in global temperatures will impact future crop yields. In the cereal crops wheat and barley, high temperatures accelerate reproductive development, reducing the number of grains per plant and final grain yield. Despite this relationship between temperature and cereal yield, it is not clear what genes and molecular pathways mediate the developmental response to increased temperatures. The plant circadian clock can respond to changes in temperature and is important for photoperiod-dependent flowering, and so is a potential mechanism controlling temperature responses in cereal crops. This study examines the relationship between temperature, the circadian clock, and the expression of flowering-time genes in barley (Hordeum vulgare), a crop model for temperate cereals. Transcript levels of barley core circadian clock genes were assayed over a range of temperatures. Transcript levels of core clock genes CCA1, GI, PRR59, PRR73, PRR95, and LUX are increased at higher temperatures. CCA1 and PRR73 respond rapidly to a decrease in temperature whereas GI and PRR59 respond rapidly to an increase in temperature. The response of GI and the PRR genes to changes in temperature is lost in the elf3 mutant indicating that their response to temperature may be dependent on a functional ELF3 gene.

Arabidopsis Intracellular NHX-Type Sodium-Proton Antiporters are Required for Seed Storage Protein Processing.

The Arabidopsis intracellular sodium-proton exchanger (NHX) proteins AtNHX5 and AtNHX6 have a well-documented role in plant development, and have been used to improve salt tolerance in a variety of species. Despite evidence that intracellular NHX proteins are important in vacuolar trafficking, the mechanism of this role is poorly understood. Here we show that NHX5 and NHX6 are necessary for processing of the predominant seed storage proteins, and also influence the processing and activity of a vacuolar processing enzyme. Furthermore, we show by yeast two-hybrid and bimolecular fluorescence complementation (BiFC) technology that the C-terminal tail of NHX6 interacts with a component of Retromer, another component of the cell sorting machinery, and that this tail is critical for NHX6 activity. These findings demonstrate that NHX5 and NHX6 are important in processing and activity of vacuolar cargo, and suggest a mechanism by which NHX intracellular (IC)-II antiporters may be involved in subcellular trafficking.

Knowing when to seek anger: Psychological health and context-sensitive emotional preferences.

According to hedonic approaches to psychological health, healthy individuals should pursue pleasant and avoid unpleasant emotions. According to instrumental approaches, however, healthy individuals should pursue useful and avoid harmful emotions, whether pleasant or unpleasant. We sought to reconcile these approaches by distinguishing between preferences for emotions that are aggregated across contexts and preferences for emotions within specific contexts. Across five days, we assessed daily confrontational and collaborative demands and daily preferences for anger and happiness. Somewhat consistent with hedonic approaches, when averaging across contexts, psychologically healthier individuals wanted to feel less anger, but not more happiness. Somewhat consistent with instrumental approaches, when examined within contexts, psychologically healthier individuals wanted to feel angrier in more confrontational contexts, and some wanted to feel happier in more collaborative contexts. Thus, although healthier individuals are motivated to avoid unpleasant emotions over time, they are more motivated to experience them when they are potentially useful.

Preferring familiar emotions: as you want (and like) it?

Do people want to feel emotions that are familiar to them? In two studies, participants rated how much they typically felt various emotions (i.e., familiarity of the emotion) and how much they generally wanted to experience these emotions. We found that, in general, people wanted to feel pleasant emotions more than unpleasant emotions. However, for both pleasant and unpleasant emotions, people more (vs. less) familiar with an emotion also wanted to experience it more. Links between the familiarity of an emotion and wanting to experience that emotion were not explained by the concurrent experience of familiar emotions. Also, we show that although familiar emotions were also liked more, liking did not fully account for wanting familiar emotions. Finally, the familiarity of emotions mediated the links between trait affect and the emotions people wanted to feel. We propose that people are motivated to feel familiar emotions, in part, because of their instrumental value.

DESPERATELY SEEKING HAPPINESS: VALUING HAPPINESS IS ASSOCIATED WITH SYMPTOMS AND DIAGNOSIS OF DEPRESSION.

Culture shapes the emotions people feel and want to feel. In Western cultures, happiness is an emotion that many people want to feel. Although experiencing happiness is associated with increased well-being and psychological health, recent evidence suggests wanting to feel happy to an extreme degree, or, highly valuing happiness, leads to decreased well-being. To examine whether these effects of valuing happiness might extend to clinical outcomes, we examined the hypothesis that depression is associated with highly valuing happiness. To do so, we examined the relationship between valuing happiness and depression in two U.S. samples. As hypothesized, valuing happiness was associated with increased depressive symptoms in a community sample with remitted major depressive disorder (MDD), even when controlling for social desirability and neuroticism (Study 1). Furthermore, valuing happiness was elevated in a remitted MDD sample (vs. healthy controls), even when controlling for current depressive symptoms, general affect valuation, and extreme goal pursuit (Study 2). Taken together, these findings suggest that the culturally-pervasive value placed on attaining happiness can represent a risk factor for symptoms and a diagnosis of depression. More broadly, they indicate that a cultural approach can meaningfully extend our understanding of clinical phenomena.

Personality Trait Change Across a Major Global Stressor.

The current research examined three related questions in a 21-month longitudinal study of a diverse sample of U.S. participants (N = 504): (a) How did Big Five traits change during the COVID-19 pandemic? (b) What factors were associated with individual differences in trait change? and (c) How was Big Five trait change associated with downstream well-being, mental health, and physical health? On average, across the 21-month study period, conscientiousness increased slightly, and extraversion decreased slightly. Individual trajectories varied around these average trajectories, and although few factors predicted these individual differences, greater increases in conscientiousness, extraversion, and agreeableness, and greater decreases in neuroticism were associated better well-being and fewer mental and physical health symptoms. The present research provides evidence that traits can change in the context of a major global stressor and that socially desirable patterns of trait change are associated with better health.