• Characterization of a cell death-inducing endonuclease-like venom protein from the parasitoid wasp Pteromalus puparum (Hymenoptera: Pteromalidae)

      Wang, Jiale; Yan, Zhichao; Xiao, Shan; Wang, Beibei; Fang, Qi; Schlenke, Todd; Ye, Gongyin; Univ Arizona, Dept Entomol (JOHN WILEY & SONS LTD, 2020-07-16)
      BACKGROUND Parasitoid wasps are valuable natural enemies for controlling pests. To ensure successful parasitism, these wasps inject venoms along with their eggs that are deposited either into or on their hosts. Parasitoid venoms regulate host behaviors, development, metabolism and immune responses. Pteromalus puparum is a pupal endoparasitoid that parasitizes a number of butterflies, including the worldwide pest cabbage butterfly, Pieris rapae. Venom from P. puparum has a variety of effects on host hemocytes, including alteration of absolute and relative hemocyte counts, and inhibition of hemocyte spreading and encapsulation. In particular, P. puparum venom causes hemocyte cell death in vivo and in vitro. RESULTS Using assay-guided chromatography, a cell death-inducing venom fraction was identified and defined as P. puparum endonuclease-like venom protein (PpENVP). It belongs to the DNA/RNA nonspecific endonuclease family, which contains two conserved endonuclease activation sites. We analyzed its expression profiles and demonstrated that PpENVP inhibits gene expression in transfected cells relying on two activation sites. However, RNA interference of PpENVP did not significantly reduce P. puparum venom cytotoxicity, suggesting that PpENVP may not be the sole cytotoxic factor present. CONCLUSION Our results provide novel insight into the function of the P. puparum venom cocktail and identify a promising insecticide candidate endonuclease that targets insect hemocytes.
    • Defoliation-induced compensatory transpiration is compromised in SUT4‐RNAi Populus

      Harding, Scott A; Frost, Christopher J; Tsai, Chung-Jui; Univ Arizona, BIO5 Inst (JOHN WILEY & SONS LTD, 2020-09-28)
      The tonoplast sucrose transporter PtaSUT4 is well expressed in leaves of Populus tremula × Populus alba (INRA 717-IB4), and its inhibition by RNA-interference (RNAi) alters leaf sucrose homeostasis. Whether sucrose partitioning between the vacuole and the cytosol is modulated by PtaSUT4 for specific physiological outcomes in Populus remains unexplored. In this study, partial defoliation was used to elicit compensatory increases in photosynthesis and transpiration by the remaining leaves in greenhouse-grown poplar. Water uptake, leaf gas exchange properties, growth and nonstructural carbohydrate abundance in source and sink organs were then compared between wild-type and SUT4-RNAi lines. Partial defoliation increased maximum photosynthesis rates similarly in all lines. There was no indication that source leaf sugar levels changed differently between wild-type and RNAi plants following partial defoliation. Sink levels of hexose (glucose and fructose) and starch decreased similarly in all lines. Interestingly, plant water uptake after partial defoliation was not as well sustained in RNAi as in wild-type plants. While the compensatory increase in photosynthesis was similar between genotypes, leaf transpiration increased less robustly in RNAi than wild-type plants. SUT4-RNAi and wild-type source leaves differed constitutively in their bulk modulus of elasticity, a measure of leaf turgor, and storage water capacitance. The data demonstrate that reduced sucrose partitioning due to PtaSUT4-RNAi altered turgor control and compensatory transpiration capacity more strikingly than photosynthesis and sugar export. The results are consistent with the interpretation that SUT4 may control vacuolar turgor independently of sink carbon provisioning.
    • Elevated Glycated Hemoglobin Is Associated With Liver Fibrosis, as Assessed by Elastography, in a Population‐Based Study of Mexican Americans

      Watt, Gordon P.; De La Cerda, Isela; Pan, Jen‐Jung; Fallon, Michael B.; Beretta, Laura; Loomba, Rohit; Lee, Miryoung; McCormick, Joseph B.; Fisher‐Hoch, Susan P.; Univ Arizona, Coll Med Phoenix, Dept Med; et al. (JOHN WILEY & SONS LTD, 2020-10-31)
      Diabetes is associated with liver disease and risk of hepatocellular carcinoma. In this study, we evaluated the association between liver fibrosis measured by transient elastography and four glucose metabolism measures in the Cameron County Hispanic Cohort, a population-based, randomly selected cohort of Mexican American Hispanics with high rates of diabetes and liver cancer. We measured liver fibrosis (a risk factor for hepatocellular carcinoma) in 774 well-characterized cohort participants using transient elastography. We evaluated the association of liver fibrosis with glycated hemoglobin (HbA1c), fasting blood glucose, insulin, and insulin resistance using multivariable linear regression models. In multivariable models, log-transformed HbA1c had the strongest association with liver fibrosis (beta = 0.37, 95% confidence interval [CI] 0.04-0.69, P = 0.038), after controlling for waist circumference, aspartate aminotransferase, alanine aminotransferase, liver fat, and other known confounders. The association was statistically significant among women (beta = 0.33, 95% CI 0.10-0.56, P = 0.009) and similar but nonsignificant among men (beta = 0.41, 95% CI -0.17 to 0.98, P = 0.593). Waist circumference, platelet count, aspartate transaminase, and liver steatosis were each associated with liver stiffness. Conclusions: Elevated HbA1c is associated with liver fibrosis, a key risk factor for HCC, particularly among women. Our results indicate that Mexican Americans with uncontrolled HbA1c may benefit from routine screening by liver elastography to identify individuals at risk of liver disease progression.
    • Evolution of diet across the animal tree of life

      Román-Palacios, Cristian; Scholl, Joshua P; Wiens, John J; Univ Arizona, Dept Ecol & Evolutionary Biol (JOHN WILEY & SONS LTD, 2019-07-09)
      What an animal eats is a fundamental aspect of its biology, but the evolution of diet has not been studied across animal phylogeny. Here, we performed a large-scale phylogenetic analysis to address three unresolved questions about the evolution of animal diets. (i) Are diets conserved across animal phylogeny? (ii) Does diet influence rates of species proliferation (diversification) among animal phyla? (iii) What was the ancestral diet of animals and major animal clades? We analyzed diet data for 1087 taxa, proportionally sampled among animal phyla based on the relative species richness of phyla. Our survey suggests that across animals, carnivory is most common (similar to 63%), herbivory less common (similar to 32%), and omnivory relatively rare (similar to 3%). Despite considerable controversy over whether ecological traits are conserved or labile, we found strong conservatism in diet over extraordinarily deep timescales. We found that diet is unrelated to rates of species diversification across animal phyla, contrasting with previous studies showing that herbivory increased diversification within some important groups (e.g., crustaceans, insects, and mammals). Finally, we estimated that the ancestor of all animals was most likely carnivorous, as were many major phyla (e.g., arthropods, molluscs, and chordates). Remarkably, our results suggest that many carnivorous species living today may have maintained this diet through a continuous series of carnivorous ancestors for >800 million years.
    • Exalted Purchases or Tainted Donations? Self‐signaling and the Evaluation of Charitable Incentives

      Savary, Jennifer; Li, Charis X.; Newman, George E.; Univ Arizona (JOHN WILEY & SONS LTD, 2020-02-20)
      It is common for charities to bundle donation requests with some type of product, such as a tote bag, pen, or coffee mug. The current studies find that people are more likely to donate when those bundles are framed as "charitable purchases" vs. "donations with a gift." We show that this effect arises because consumers want to avoid the negative self-signal associated with receiving a gift in exchange for donating. Five experiments provide evidence for the role of self-signaling, identify key moderators of the framing effect, and demonstrate the downstream consequences for people's likelihood of donating in the future. More broadly, the current studies lend further evidence to the role of self-signaling in charitable giving and provide greater clarity regarding how and when different donation solicitation techniques may be most effective.
    • N-6-methyladenosine and RNA secondary structure affect transcript stability and protein abundance during systemic salt stress in Arabidopsis

      Kramer, Marianne C.; Janssen, Kevin A.; Palos, Kyle; Nelson, Andrew D. L.; Vandivier, Lee E.; Garcia, Benjamin A.; Lyons, Eric; Beilstein, Mark A.; Gregory, Brian D.; Univ Arizona, Sch Plant Sci; et al. (JOHN WILEY & SONS LTD, 2020-07)
      After transcription, a messenger RNA (mRNA) is further post-transcriptionally regulated by several features including RNA secondary structure and covalent RNA modifications (specifically N-6-methyladenosine, m(6)A). Both RNA secondary structure and m(6)A have been demonstrated to regulate mRNA stability and translation and have been independently linked to plant responses to soil salinity levels. However, the effect of m(6)A on regulating RNA secondary structure and the combinatorial interplay between these two RNA features during salt stress response has yet to be studied. Here, we globally identify RNA-protein interactions and RNA secondary structure during systemic salt stress. This analysis reveals that RNA secondary structure changes significantly during salt stress, and that it is independent of global changes in RNA-protein interactions. Conversely, we find that m(6)A is anti-correlated with RNA secondary structure in a condition-dependent manner, with salt-specific m(6)A correlated with a decrease in mRNA secondary structure during salt stress. Taken together, we suggest that salt-specific m(6)A deposition and the associated loss of RNA secondary structure results in increases in mRNA stability for transcripts encoding abiotic stress response proteins and ultimately increases in protein levels from these stabilized transcripts. In total, our comprehensive analyses reveal important post-transcriptional regulatory mechanisms involved in plant long-term salt stress response and adaptation.
    • Plant science decadal vision 2020-2030: Reimagining the potential of plants for a healthy and sustainable future

      Henkhaus, Natalie; Bartlett, Madelaine; Gang, David; Grumet, Rebecca; Jordon-Thaden, Ingrid; Lorence, Argelia; Lyons, Eric; Miller, Samantha; Murray, Seth; Nelson, Andrew; et al. (JOHN WILEY & SONS LTD, 2020-08)
      Plants, and the biological systems around them, are key to the future health of the planet and its inhabitants. The Plant Science Decadal Vision 2020-2030 frames our ability to perform vital and far-reaching research in plant systems sciences, essential to how we value participants and apply emerging technologies. We outline a comprehensive vision for addressing some of our most pressing global problems through discovery, practical applications, and education. The Decadal Vision was developed by the participants at the Plant Summit 2019, a community event organized by the Plant Science Research Network. The Decadal Vision describes a holistic vision for the next decade of plant science that blends recommendations for research, people, and technology. Going beyond discoveries and applications, we, the plant science community, must implement bold, innovative changes to research cultures and training paradigms in this era of automation, virtualization, and the looming shadow of climate change. Our vision and hopes for the next decade are encapsulated in the phrase reimagining the potential of plants for a healthy and sustainable future. The Decadal Vision recognizes the vital intersection of human and scientific elements and demands an integrated implementation of strategies for research (Goals 1-4), people (Goals 5 and 6), and technology (Goals 7 and 8). This report is intended to help inspire and guide the research community, scientific societies, federal funding agencies, private philanthropies, corporations, educators, entrepreneurs, and early career researchers over the next 10 years. The research encompass experimental and computational approaches to understanding and predicting ecosystem behavior; novel production systems for food, feed, and fiber with greater crop diversity, efficiency, productivity, and resilience that improve ecosystem health; approaches to realize the potential for advances in nutrition, discovery and engineering of plant-based medicines, and "green infrastructure." Launching the Transparent Plant will use experimental and computational approaches to break down the phytobiome into a "parts store" that supports tinkering and supports query, prediction, and rapid-response problem solving. Equity, diversity, and inclusion are indispensable cornerstones of realizing our vision. We make recommendations around funding and systems that support customized professional development. Plant systems are frequently taken for granted therefore we make recommendations to improve plant awareness and community science programs to increase understanding of scientific research. We prioritize emerging technologies, focusing on non-invasive imaging, sensors, and plug-and-play portable lab technologies, coupled with enabling computational advances. Plant systems science will benefit from data management and future advances in automation, machine learning, natural language processing, and artificial intelligence-assisted data integration, pattern identification, and decision making. Implementation of this vision will transform plant systems science and ripple outwards through society and across the globe. Beyond deepening our biological understanding, we envision entirely new applications. We further anticipate a wave of diversification of plant systems practitioners while stimulating community engagement, underpinning increasing entrepreneurship. This surge of engagement and knowledge will help satisfy and stoke people's natural curiosity about the future, and their desire to prepare for it, as they seek fuller information about food, health, climate and ecological systems.
    • Secrets and Likes: The Drive for Privacy and the Difficulty of Achieving It in the Digital Age

      Acquisti, Alessandro; Brandimarte, Laura; Loewenstein, George; Univ Arizona (JOHN WILEY & SONS LTD, 2020-09-06)
      We review different streams of social science literature on privacy with the goal of understanding consumer privacy decision making and deriving implications for policy. We focus on psychological and economic factors influencing both consumers' desire and consumers' ability to protect their privacy, either through individual action or through the implementation of regulations applying to firms. Contrary to depictions of online sharing behaviors as careless, we show how consumers fundamentally care about online privacy, and present evidence of numerous actions they take to protect it. However, we also document how prohibitively difficult it is to attain desired, or even desirable, levels of privacy through individual action alone. The remaining instrument for privacy protection is policy intervention. However, again for both psychological and economic reasons, the collective impetus for adequate intervention is often countervailed by powerful interests that oppose it.
    • Untargeted metabolomic profiling of Sphagnum fallax reveals novel antimicrobial metabolites

      Fudyma, Jane D; Lyon, Jamee; AminiTabrizi, Roya; Gieschen, Hans; Chu, Rosalie K; Hoyt, David W; Kyle, Jennifer E; Toyoda, Jason; Tolic, Nikola; Heyman, Heino M; et al. (JOHN WILEY & SONS LTD, 2019-11-12)
      Sphagnum mosses dominate peatlands by employing harsh ecosystem tactics to prevent vascular plant growth and microbial degradation of these large carbon stores. Knowledge about Sphagnum-produced metabolites, their structure and their function, is important to better understand the mechanisms, underlying this carbon sequestration phenomenon in the face of climate variability. It is currently unclear which compounds are responsible for inhibition of organic matter decomposition and the mechanisms by which this inhibition occurs. Metabolite profiling of Sphagnum fallax was performed using two types of mass spectrometry (MS) systems and 1H nuclear magnetic resonance spectroscopy (1H NMR). Lipidome profiling was performed using LC-MS/MS. A total of 655 metabolites, including one hundred fifty-two lipids, were detected by NMR and LC-MS/MS-329 of which were novel metabolites (31 unknown lipids). Sphagum fallax metabolite profile was composed mainly of acid-like and flavonoid glycoside compounds, that could be acting as potent antimicrobial compounds, allowing Sphagnum to control its environment. Sphagnum fallax metabolite composition comparison against previously known antimicrobial plant metabolites confirmed this trend, with seventeen antimicrobial compounds discovered to be present in Sphagnum fallax, the majority of which were acids and glycosides. Biological activity of these compounds needs to be further tested to confirm antimicrobial qualities. Three fungal metabolites were identified providing insights into fungal colonization that may benefit Sphagnum. Characterizing the metabolite profile of Sphagnum fallax provided a baseline to understand the mechanisms in which Sphagnum fallax acts on its environment, its relation to carbon sequestration in peatlands, and provide key biomarkers to predict peatland C store changes (sequestration, emissions) as climate shifts.