Soil compaction represents a major challenge for modern agriculture. Compaction is intuitively thought to reduce root growth by limiting the ability of roots to penetrate harder soils. We report that ...root growth in compacted soil is instead actively suppressed by the volatile hormone ethylene. We found that mutant
and rice roots that were insensitive to ethylene penetrated compacted soil more effectively than did wild-type roots. Our results indicate that soil compaction lowers gas diffusion through a reduction in air-filled pores, thereby causing ethylene to accumulate in root tissues and trigger hormone responses that restrict growth. We propose that ethylene acts as an early warning signal for roots to avoid compacted soils, which would be relevant to research into the breeding of crops resilient to soil compaction.
SUMMARY
Plants forage soil for water and nutrients, whose distribution is patchy and often dynamic. To improve their foraging activities, plants have evolved mechanisms to modify the physicochemical ...properties and microbial communities of the rhizosphere, i.e. the soil compartment under the influence of the roots. This dynamic interplay in root−soil−microbiome interactions creates emerging properties that impact plant nutrition and health. As a consequence, the rhizosphere can be considered an extended root phenotype, a manifestation of the effects of plant genes on their environment inside and/or outside of the organism. Here, we review current understanding of how plants shape the rhizosphere and the benefits it confers to plant fitness. We discuss future research challenges and how applying their solutions in crops will enable us to harvest the benefits of the extended root phenotype.
Significance Statement
Plants have evolved mechanisms to modify the physicochemical properties and microbial communities of the rhizosphere. Here, we review our current knowledge on how plants create this extended phenotype through root−soil−microbiome interactions and the benefits it confers to plant fitness.
CONSEQUENCES OF DOWNWARD ENVY YU, LINGTAO; DUFFY, MICHELLE K.; TEPPER, BENNETT J.
Academy of Management journal,
12/2018, Volume:
61, Issue:
6
Journal Article
Peer reviewed
We invoke theory and research on the social functional view of envy to propose a novel theoretical framework of supervisory leader envy of direct reports. Findings from two multi-source, multi-wave ...studies of supervisor–subordinate dyads provide support for the theses that (1) downward envy of subordinates threatens supervisors’ self-esteem and triggers adaptive strategies in the form of abusive supervision and supervisory self-improvement; and (2) supervisors are more likely to respond to downward envy induced self-esteem threat with abuse when they perceive envied subordinates to be cold and competent and they are more likely to respond with self-improvement when they perceive envied subordinates to be warm and competent.
The growth factor progranulin (PGRN) regulates cell division, survival, and migration. PGRN is an extracellular glycoprotein bearing multiple copies of the cysteine-rich granulin motif. With PGRN ...family members in plants and slime mold, it represents one of the most ancient of the extracellular regulatory proteins still extant in modern animals. PRGN has multiple biological roles. It contributes to the regulation of early embryogenesis, to adult tissue repair and inflammation. Elevated PGRN levels often occur in cancers, and PGRN immunotherapy inhibits the growth of hepatic cancer xenografts in mice. Recent studies have demonstrated roles for PGRN in neurobiology. An autosomal dominant mutation in GRN, the gene for PGRN, leads to neuronal atrophy in the frontal and temporal lobes, resulting in the disease frontotemporal lobar dementia. In this review we will discuss current knowledge of the multifaceted biology of PGRN.
Ribosomes that experience terminal stalls during translation are resolved by ribosome-associated quality control (QC) pathways that oversee mRNA and nascent chain destruction and recycle ribosomal ...subunits. The proximal factors that sense stalled ribosomes and initiate mammalian ribosome-associated QC events remain undefined. We demonstrate that the ZNF598 ubiquitin ligase and the 40S ribosomal protein RACK1 help to resolve poly(A)-induced stalled ribosomes. They accomplish this by regulating distinct and overlapping regulatory 40S ribosomal ubiquitylation events. ZNF598 primarily mediates regulatory ubiquitylation of RPS10 and RPS20, whereas RACK1 regulates RPS2, RPS3, and RPS20 ubiquitylation. Gain or loss of ZNF598 function or mutations that block RPS10 or RPS20 ubiquitylation result in defective resolution of stalled ribosomes and subsequent readthrough of poly(A)-containing stall sequences. Together, our results indicate that ZNF598, RACK1, and 40S regulatory ubiquitylation plays a pivotal role in mammalian ribosome-associated QC pathways.
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•Poly(A) sequences stall ribosomes and repress downstream translation in mammals•Ribosome stall resolution requires regulatory ubiquitylation of RPS10 and RPS20•ZNF598 and RACK1 are needed for initiation of ribosome stall resolution in mammals•ZNF598 catalyzes regulatory ribosomal ubiquitylation of RPS20, RPS10, and RPS3
Ribosomes stall on poly(A) tracts. Sundaramoorthy et. al identify regulatory ubiquitylation of RPS10 and RPS20 as a key regulator of poly(A)-induced ribosome stalling. ZNF598 catalyzes these ubiquitylation events and is needed for efficient stall resolution. Ribosome-associated RACK1 also facilitates stall resolution by mediating regulatory ubiquitylation of distinct but overlapping 40S proteins.
The holistic rhizosphere York, Larry M.; Carminati, Andrea; Mooney, Sacha J. ...
Journal of experimental botany,
06/2016, Volume:
67, Issue:
12
Journal Article
Peer reviewed
Open access
Despite often being conceptualized as a thin layer of soil around roots, the rhizosphere is actually a dynamic system of interacting processes. Hiltner originally defined the rhizosphere as the soil ...influenced by plant roots. However, soil physicists, chemists, microbiologists, and plant physiologists have studied the rhizosphere independently, and therefore conceptualized the rhizosphere in different ways and using contrasting terminology. Rather than research-specific conceptions of the rhizosphere, the authors propose a holistic rhizosphere encapsulating the following components: microbial community gradients, macroorganisms, mucigel, volumes of soil structure modification, and depletion or accumulation zones of nutrients, water, root exudates, volatiles, and gases. These rhizosphere components are the result of dynamic processes and understanding the integration of these processes will be necessary for future contributions to rhizosphere science based upon interdisciplinary collaborations. In this review, current knowledge of the rhizosphere is synthesized using this holistic perspective with a focus on integrating traditionally separated rhizosphere studies. The temporal dynamics of rhizosphere activities will also be considered, from annual fine root turnover to diurnal fluctuations of water and nutrient uptake. The latest empirical and computational methods are discussed in the context of rhizosphere integration. Clarification of rhizosphere semantics, a holistic model of the rhizosphere, examples of integration of rhizosphere studies across disciplines, and review of the latest rhizosphere methods will empower rhizosphere scientists from different disciplines to engage in the interdisciplinary collaborations needed to break new ground in truly understanding the rhizosphere and to apply this knowledge for practical guidance.
Concerns about the social consequences of conservation have spurred increased attention the monitoring and evaluation of the social impacts of conservation projects. This has resulted in a growing ...body of research that demonstrates how conservation can produce both positive and negative social economic, cultural health, and governance consequences for local communities. Yet, the results of social monitoring efforts are seldom applied to adaptively manage conservation projects. Greater attention is needed to incorporating the results of social impact assessments in long-term conservation management to minimize negative social consequences and maximize social benefits. We bring together insights from social impact assessment, adaptive management, social learning, knowledge coproduction, cross-scale governance, and environmental planning to propose a definition and framework for adaptive social impact management (ASIM). We define ASIM as the cyclical process of monitoring and adaptively managing social impacts over the life-span of an initiative through the 4 stages of profiling, learning, planning, and implementing. We outline 14 steps associated with the 4 stages of the ASIM cycle and provide guidance and potential methods for social-indicator development, predictive assessments of social impacts, monitoring and evaluation, communication of results, and identification and prioritization of management responses. Successful ASIM will be aided by engaging with best practices - including local engagement and collaboration in the process, transparent communication of results to stakeholders, collective deliberation on and choice of interventions, documentation of shared learning at the site level, and the scaling up of insights to inform higher-level conservation policiesto increase accountability, trust, and perceived legitimacy among stakeholders. The ASIM process is broadly applicable to conservation, environmental management, and development initiatives at various scales and in different contexts. Las preocupaciones sobre las consecuencias sociales de la conservación han generado un incremento en la atención puesta al monitoreo y a la evaluación de los impactos sociales de los proyectos de conservación. Esto ha resultado en un creciente cuerpo de investigación que demuestra cómo la conservación puede producir consecuencias sociales, económicas, culturales, de salud y gobernanza tanto positivas como negativas para las comunidades locales. A pesar de esto, los resultados de los esfuerzos de monitoreo social rara vez se aplican para manejar adaptativamente los proyectos de conservación. Se necesita de mayor atención para incorporar los resultados de las valoraciones del impacto social en el manejo de la conservación a largo plazo para minimizar las consecuencias sociales negativas y maximizar los beneficios sociales. Juntamos el conocimiento de la valoración del impacto social, el manejo adaptativo, el aprendizaje social, la coproducción del conocimiento, la gobernanza a través de escalas, y laplaneación ambiental para proponer una definición y un marco de trabajo para el manejo adaptativo del impacto social (ASIM). Definimos el ASIM como el proceso cíclico de monitoreo y manejo adaptativo de los impactos sociales a lo largo de la vida de una iniciativa a través de cuatro etapas de evaluación por perfil, aprendizaje, planeación e implementación. Resumimos 14 pasos asociados con las cuatro etapas del ciclo del ASIM y proporcionamos una guía y métodos potenciales para el desarrollo del indicador social, la valoración predictiva de los impactos sociales, el monitoreo y la evaluación, la comunicación de los resultados, y la identificación y priorización de las respuestas del manejo. Los ASIM exitosos serán apoyados al trabajar con las mejores prácticas - incluyendo al compromiso local y la colaboración en el proceso, la comunicación transparente de los resultados a los accionistas, la deliberación colectiva y la elección de intervenciones, la documentación del aprendizaje compartido a nivel de sitio, y el incremento de conocimiento para informar las políticas de conservación de niveles más altos para incrementar la responsabilidad, confianza y la legitimidad percibida entre los accionistas. El proceso del ASIM es aplicable en general a la conservación, el manejo ambiental y a las iniciativas de desarrollo a varias escalas y en diferentes contextos.
Abstract
Background and Objectives
Studies reporting an association between hearing loss and depression in older adults are conflicting and warrant a systematic review and meta-analysis of the ...evidence.
Research Design and Methods
A search of academic databases (e.g., MEDLINE) and gray literature (e.g., OpenGrey) identified relevant articles published up to July 17, 2018. Cross-sectional or cohort designs were included. Outcome effects were computed as odds ratios (ORs) and pooled using random-effects meta-analysis (PROSPERO: CRD42018084494).
Results
A total of 147,148 participants from 35 studies met inclusion criteria. Twenty-four studies were cross-sectional and 11 were cohort designs. Overall, hearing loss was associated with statistically significantly greater odds of depression in older adults (OR = 1.47, 95% confidence interval CI = 1.31−1.65). When studies were stratified by design, hearing loss was associated with greater odds of depression in cross-sectional studies (OR = 1.54, 95% CI = 1.31−1.80) and cohort studies (OR = 1.39, 95% CI = 1.16 − 1.67), and there was no difference between cross-sectional or cohort effect estimates (Q = 0.64, p = .42). There was no effect of moderator variables (i.e., hearing aid use) on the association between hearing loss and depression, but these findings must be interpreted with caution. There was no presence of publication bias but certainty in the estimation of the overall effect was classified as “low.”
Discussion and Implications
Older adults may experience increased odds of depression associated with hearing loss, and this association may not be influenced by study or participant characteristics.
The correct decoding of messenger RNAs (mRNAs) into proteins is an essential cellular task. The translational process is monitored by several quality control (QC) mechanisms that recognize defective ...translation complexes in which ribosomes are stalled on substrate mRNAs. Stalled translation complexes occur when defects in the mRNA template, the translation machinery, or the nascent polypeptide arrest the ribosome during translation elongation or termination. These QC events promote the disassembly of the stalled translation complex and the recycling and/or degradation of the individual mRNA, ribosomal, and/or nascent polypeptide components, thereby clearing the cell of improper translation products and defective components of the translation machinery.
...C. tropicalis, C. parapsilosis, C. guilliermondii, C. lusitaniae, C. famata, C. rugosa, and C. dubliniensis form part of the Candida CTG clade and translate CTG codons as serine instead of ...leucine. ...even within a clade, the genetic distance between any two NAC species is often larger than the genetic distance between humans and some fishes 18. ...in no way should it be argued that C. albicans makes the rules for all NAC species.
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