Mechanistic characterization of the 5′-triphosphate-dependent activation of PKR: Lack of 5′-end nucleobase specificity, evidence for a distinct triphosphate binding site, and a critical role for the dsRBD

The protein kinase PKR is activated by RNA to phosphorylate eIF-2α, inhibiting translation initiation. Long dsRNA activates PKR via interactions with the dsRNA-binding domain (dsRBD). Weakly structured RNA also activates PKR and does so in a 5′-triphosphate (ppp)–dependent fashion, however relatively little is known about this pathway. We used a mutant T7 RNA polymerase to incorporate all four triphosphate-containing nucleotides into the first position of a largely single-stranded RNA and found absence of selectivity, in that all four transcripts activate PKR. Recognition of 5′-triphosphate, but not the nucleobase at the 5′-most position, makes this RNA-mediated innate immune response sensitive to a broad array of viruses. PKR was neither activated in the presence of γ-GTP nor recognized NTPs other than ATP in activation competition and ITC binding assays. This indicates that the binding site for ATP is selective, which contrasts with the site for the 5′ end of ppp-ssRNA. Activation experiments reveal that short dsRNAs compete with 5′-triphosphate RNAs and heparin for activation, and likewise gel-shift assays reveal that activating 5′-triphosphate RNAs and heparin compete with short dsRNAs for binding to PKR's dsRBD. The dsRBD thus plays a critical role in the activation of PKR by ppp-ssRNA and even heparin. At the same time, cross-linking experiments indicate that ppp-ssRNA interacts with PKR outside of the dsRBD as well. Overall, 5′-triphosphate-containing, weakly structured RNAs activate PKR via interactions with both the dsRBD and a distinct triphosphate binding site that lacks 5′-nucleobase specificity, allowing the innate immune response to provide broad-spectrum protection from pathogens

Evaluating Sustainability on the Cal Poly Campus: Attitudes, Behaviors, Knowledge, Social Norms, and Social Desirability

Previous research has shown that attitudes and behavior towards sustainability are not correlated. Social factors including norms and desirability have been found to explain these results. One hundred and six students from California Polytechnic State University participated in this study. The survey used was composed of several sections: attitudes, behaviors, knowledge, social norms, social desirability, and a demographic section. Attitudes and behaviors were found to be correlated in this study. Knowledge and behavior towards sustainability was not found to be correlated as expected. Participants’ attitudes were correlated with friends’ and families’ but not professors’ and peers’ attitudes. Participants’ behaviors were correlated only with friends’ attitudes. This study is particularly relevant for colleges who are moving towards a sustainable future and wish to measure the effectiveness of the movement

Public estimates of support for offshore wind energy: False consensus, pluralistic ignorance, and partisan effects

Meeting future energy demands will require large-scale implementation of renewable energy projects. If one of these energy sources—offshore wind—becomes a common sight off coastlines, consideration of local public opinion and action will be critical. Previous research from the social sciences has lacked depth in examining the underlying factors that shape public opinion towards offshore wind development. The current research brings a new perspective to the literature by showing that how members of the public perceive support among others relates to their own opinions of offshore wind energy. We report results from two surveys. The first focused on opinion formation relating to offshore wind in general among New England residents, while the second focused on a specific offshore wind project in Rhode Island. We find evidence that both supporters and opponents of offshore wind underestimate levels of support among others, indicating a pluralistic ignorance effect and false consensus effect, respectively. We also find distinct patterns of perceived support among self-identified Republicans and Democrats. The findings hold important implications for policymakers and developers in understanding the nature of public support and opposition for offshore wind energy, particularly with respect to individuals’ willingness to publicly engage with offshore wind projects

Continent-wide analysis of how urbanization affects bird-window collision mortality in North America

Characteristics of buildings and land cover surrounding buildings influence the number of bird-window collisions, yet little is known about whether bird-window collisions are associated with urbanization at large spatial scales. We initiated a continent-wide study in North America to assess how bird-window collision mortality is influenced by building characteristics, landscaping around buildings, and regional urbanization. In autumn 2014, researchers at 40 sites (N = 281 buildings) used standardized protocols to document collision mortality of birds, evaluate building characteristics, and measure local land cover and regional urbanization. Overall, 324 bird carcasses were observed (range = 0–34 per site) representing 71 species. Consistent with previous studies, we found that building size had a strong positive effect on bird-window collision mortality, but the strength of the effect on mortality depended on regional urbanization. The positive relationship between collision mortality and building size was greatest at large buildings in regions of low urbanization, locally extensive lawns, and low-density structures. Collision mortality was consistently low for small buildings, regardless of large-scale urbanization. The mechanisms shaping broad-scale variation in collision mortality during seasonal migration may be related to habitat selection at a hierarchy of scales and behavioral divergence between urban and rural bird populations. These results suggest that collision prevention measures should be prioritized at large buildings in regions of low urbanization throughout North America