Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of (Sphingidae) initiated feeding faster and gained more weight on (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.

This study is original and advances knowledge on the reasons for the slow adoption of health IT in nursing homes. It finds that lack of adequate information regarding the utility and benefits of health IT in management adoption decisions can result in haphazard implementation or no adoption at all. This finding has significant value for policy makers' practitioners for improving accessibility of information regarding the use of health IT in nursing homes that could address the health IT adoption challenge in this industry.

The feasibility of using the highly purified native attachment (G) protein in a subunit vaccine against respiratory syncytial virus (RSV) was examined in a murine model with or without the fusion (F) protein of RSV and the adjuvant QS-21. The studies established that QS-21 was more potent than AlOH as an adjuvant for both F and G glycoproteins. Augmented antigen-dependent killer cell activity and complement-assisted serum neutralizing and anti-F and G protein immunoglobulin G2a antibody titers were observed. Immunization with G/QS-21 generated immune responses that were characterized by low levels of antigen-dependent killer cell activity, elevated levels of interleukin-5 (IL-5) and percentages of eosinophils in the bronchoalveolar lavage fluids after challenge, and splenic immunocytes that secreted IL-5 but not gamma interferon (IFN-␥) after in vitro stimulation with purified whole virus antigens. The pulmonary eosinophilia was similar to that induced by a facsimile of a formalin-inactivated vaccine used in previous clinical trials and was prevented by prior in vivo treatment with anti-IL-5 but not with control immunoglobulin G or anti-IFN-␥ neutralizing monoclonal antibodies. Thus the data implied that vaccination with G/QS-21 generated helper T-cell immune responses that were type 2 in nature. Alternatively, the data suggested that the helper T-cell immune responses elicited by F/QS-21 were more type 1 in character. Neither eosinophilia nor elevated levels of IL-5 were observed in the lungs of mice after challenge. Noteworthy levels of antigen-dependent killer cell activity was observed, and splenic immunocytes secreted copious quantities of IFN-␥. Immunization with a combination vaccine composed of highly purified native F and G proteins plus QS-21 (F؉G/QS-21) resulted in augmented complement-assisted serum neutralizing antibody titers compared with vaccination with either F/QS-21 or G/QS-21 alone. However, following vaccination with F؉G/QS-21, the bronchoalveolar lavage fluids contained significant increases in IL-5 and percentages of eosinophils after challenge, the spleen cells appeared to secrete less IFN-␥ after in vitro stimulation, and there was no evidence of increased numbers of antigen-dependent killer cell precursors. Taken together, the data imply that native G protein influences the nature of the immune responses elicited by F/QS-21. The results therefore suggest that G, not F, protein has more potential to bias the host for atypical pulmonary inflammatory responses.

In eukaryotes, secretory proteins are folded and assembled in the endoplasmic reticulum (ER). Many heterologous proteins are retained in the ER due to suboptimal folding conditions. We previously reported that heterologous secretion of Pyrococcus furiosus beta-glucosidase in Saccharomyces cerevisiae resulted in the accumulation of a large fraction of inactive beta-glucosidase in the ER. In this work, we determine the effect of introducing additional genes of ER-resident yeast proteins, Kar2p (binding protein [BiP]) and protein disulfide isomerase (PDI), on relieving this bottleneck. Single-copy expression of BiP and PDI worked synergistically to improve secretion by reverse similar 60%. In an effort to optimize BiP and PDI interactions, we created a library of beta-glucosidase expression strains that incorporated four combinations of constitutively or inducibly-expressed BiP and PDI genes integrated to random gene copynumbers in the yeast chromosome. Approximately 15% of the transformants screened had secretion level improvements higher than that seen with single BiP/PDI gene overexpression, and the highest secreting strain had threefold higher beta-glucosidase levels than the control. Nineteen of the improved strains were re-examined for beta-glucosidase secretion as well as BiP and PDI levels. Within the improved transformants BiP and PDI levels ranged sevenfold and tenfold over the control, respectively. Interestingly, increasing BiP levels decreased beta-glucosidase secretion, whereas increasing PDI levels increased beta-glucosidase secretion. The action of PDI was unexpected because beta-glucosidase is not a disulfide-bonded protein. We suggest that PDI may be acting in a chaperone-like capacity or possibly creating mixed disulfides with the beta-glucosidase's lone cysteine residue during the folding and assembly process.

Scholarly literature fi nds positive motivational eff ects of matching workers and missions. However, the psychological mechanisms behind this matching eff ect have not been explored. Th is article develops and tests a moderated mediation model of mission matching in which meaningfulness serves as an intervening mechanism that explains the association between mission matching and eff ort. It also considers how individual diff erences in prosocial motivation infl uence the intervening role of meaningfulness. Using a real-eff ort laboratory experiment with monetary incentives, the article shows that matched subjects exert more eff ort than mismatched subjects, that this eff ect is mediated by increases in meaningfulness, that prosociality moderates the eff ect of a match on meaningfulness, and that the indirect eff ect of a match on eff ort through increases in meaningfulness varies as a function of prosociality. Th ese results contribute to a more nuanced understanding of mission matching and suggest that matching may be particularly important for certain types of workers. Practitioner Points• Matching workers with missions can enhance productivity and the meaningfulness of work.• Th e results stress the importance of personnel screening and selection for managing mission-driven organizations. • In addition to investing in improving personnel screening and selection, managers may focus on attracting applicants who share the organization's mission by clearly communicating the purpose and values of the organization to applicants.Th e Motivational Eff ects of Mission Matching: A Lab-Experimental Test of a Moderated Mediation Model M any organizations exist to tackle social problems. For these mission-oriented organizations, the social mission is a central feature of organizational life. Th e centrality of mission to life in public and nonprofi t organizations is one of their defi ning features and one of the qualities that sets them apart from traditional business organizations. Mission is also important because it has motivational properties (Rainey and Steinbauer 1999;Weiss 1996;Weiss and Piderit 1999;Wright 2007). It plays a role in two decisions that organizations rely on workers to make: participation and performance. To the extent possible, workers seek opportunities to join organizations that share their mission, and it is thought that support for the mission will translate into happier and more productive workers (Brown and Yoshioka 2003;Cantarelli, Belardinelli, and Bellé 2015;Hassan 2014;Wright 2007; Wright and Pandey 2011).Th e existence of a social mission does not by itself guarantee high motivation levels. Formal models from economics and empirical studies from the person-organization fi t literature show that concordance between individuals and their organization matters (Akerlof and Kranton 2005;Besley and Ghatak 2005;Bright 2008;Dur and Zoutenbier 2014;Kristof 1996;Steijn 2008;Wright and Pandey 2008). Th e positive motivational properties of organizational mission may be tapped only when there is, a...

Archaeal enzymes have great potential for industrial use; however, expressing them in their natural hosts has proven challenging. Growth conditions for many archaea are beyond typical fermentation capabilities, and to compound the problem, archaea generally achieve much lower biomass yields than Escherichia coli or Saccharomyces cerevisiae. To determine whether a eukaryotic host, S. cerevisiae, would be a suitable alternative for archaeal protein production, we examined the expression of the tetrameric beta-glucosidase from the hyperthermophilic archaeon Pyrococcus furiosus. We engineered the beta-glucosidase to facilitate secretion into the culture medium and have demonstrated the beta-glucosidase's secretion and activity. We determined the dependence of beta-glucosidase secretion on gene copy number and obtained a transformant capable of secreting approximately 10 mg/L in batch culture. All transformants retained large intracellular fractions of beta-glucosidase, indicative of an intracellular bottleneck. Cell fractionation by sucrose density centrifugation and immunofluorescence identified the endoplasmic reticulum as the secretion bottleneck. Preliminary evidence indicates that the cause of this bottleneck is misfolding of the monomeric beta-glucosidase, rather than tetrameric association. Expression at moderately elevated temperatures (between 30 and 40 degrees C) improved beta-glucosidase yields, suggesting that higher temperature expression may improve folding and secretion yields.

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