Search

Across eumetazoans, the ability to perceive and respond to visual stimuli is largely mediated by opsins, a family of proteins belonging to the G protein-coupled receptor (GPCR) superclass. Lineage-specific gains and losses led to a striking diversity in the numbers, types, and spectral sensitivities conferred by visual opsin gene expression. Here, we review the diversity of visual opsins and differences in opsin gene expression from well-studied protostome, invertebrate deuterostome, and cnidarian groups. We discuss the functional significance of opsin expression differences and spectral tuning among lineages. In some cases, opsin evolution has been linked to the detection of relevant visual signals, including sexually selected color traits and host plant features. In other instances, variation in opsins has not been directly linked to functional or ecological differences. Overall, the array of opsin expression patterns and sensitivities across invertebrate lineages highlight the diversity of opsins in the eumetazoan ancestor and the labile nature of opsins over evolutionary time.

Households’ willingness to pay (WTP) for water quality improvements—representing their economic value—depends on where improvements occur. Households often hold higher values for improvements close to their homes or iconic areas. Are there other areas where improvements might hold high value to individual households, do effects on WTP vary by type of improvement, and can these areas be identified even if they are not anticipated by researchers? To answer these questions, we integrated a water quality model and map-based, interactive choice experiment to estimate households’ WTP for water quality improvements throughout a river network covering six New England states. The choice experiment was implemented using a push-to-web survey over a sample of New England households. Voting scenarios used to elicit WTP included interactive geographic information system (GIS) maps that illustrated three water quality measures at various zoom levels across the study domain. We captured data on how respondents maneuvered through these maps prior to answering the value-eliciting questions. Results show that WTP was influenced by regionwide quality improvements and improvements surrounding each respondent’s home, as anticipated, but also by improvements in individualized locations identifiable via each respondent’s map interactions. These spatial WTP variations only appear for low-quality rivers and are focused around particular areas of New England. The study shows that dynamic map interactions can convey salient information for WTP estimation and that predicting spatial WTP heterogeneity based primarily on home or iconic locations, as typically done, may overlook areas where water quality has high value.

Supplementary Figures 1-10

CD96 is a novel target for cancer immunotherapy shown to regulate NK cell effector function and metastasis. Here, we demonstrated that blocking CD96 suppressed primary tumor growth in a number of experimental mouse tumor models in a CD8+ T cell–dependent manner. DNAM-1/CD226, Batf3, IL12p35, and IFNγ were also critical, and CD96-deficient CD8+ T cells promoted greater tumor control than CD96-sufficient CD8+ T cells. The antitumor activity of anti-CD96 therapy was independent of Fc-mediated effector function and was more effective in dual combination with blockade of a number of immune checkpoints, including PD-1, PD-L1, TIGIT, and CTLA-4. We consistently observed coexpression of PD-1 with CD96 on CD8+ T lymphocytes in tumor-infiltrating leukocytes both in mouse and human cancers using mRNA analysis, flow cytometry, and multiplex IHF. The combination of anti-CD96 with anti–PD-1 increased the percentage of IFNγ-expressing CD8+ T lymphocytes. Addition of anti-CD96 to anti–PD-1 and anti-TIGIT resulted in superior antitumor responses, regardless of the ability of the anti-TIGIT isotype to engage FcR. The optimal triple combination was also dependent upon CD8+ T cells and IFNγ. Overall, these data demonstrate that CD96 is an immune checkpoint on CD8+ T cells and that blocking CD96 in combination with other immune-checkpoint inhibitors is a strategy to enhance T-cell activity and suppress tumor growth.

Supp Methods and Legends S1-S10

Purpose:Natural killer (NK) cells play a critical role in tumor immunosurveillance. Multiple activating and inhibitory receptors (IR) regulate NK-cell–mediated tumor control. The IR T-cell immunoglobulin and ITIM domain (TIGIT) and its counter-receptor CD226 exert opposite effects on NK-cell–mediated tumor reactivity.Experimental Design:We evaluated the frequency, phenotype, and functions of NK cells freshly isolated from healthy donors and patients with melanoma with multiparameter flow cytometry. We assessed TIGIT and CD226 cell surface expression and internalization upon binding to CD155. We evaluated the role of IL15 and TIGIT blockade in increasing NK-cell–mediated cytotoxicity in vitro and in two mouse models.Results:NK cells are present at low frequencies in metastatic melanoma, are dysfunctional, and downregulate both TIGIT and CD226 expression. As compared with TIGIT− NK cells, TIGIT+ NK cells exhibit higher cytotoxic capacity and maturation, but paradoxically lower cytotoxicity against CD155+ MHC class I–deficient melanoma cells. Membrane bound CD155 triggers CD226 internalization and degradation, resulting in decreased NK-cell–mediated tumor reactivity. IL15 increases TIGIT and CD226 gene expression by tumor-infiltrating NK cells (TiNKs) and, together with TIGIT blockade, increases NK-cell–mediated melanoma cytotoxicity in vitro and decreases tumor metastasis in two mouse melanoma models. Specific deletion of TIGIT on transferred NK cells enhances the antimetastatic activity of IL15, while CD226 blockade decreases the effects of IL15 and TIGIT blockade.Conclusions:Our findings support the development of novel combinatorial immunotherapy with IL15 and TIGIT blockade to promote NK-cell–mediated destruction of MHC class I–deficient melanoma, which are refractory to CD8+ T-cell–mediated immunity.See related commentary by Pietra et al., p. 5274

Supplemental Figure 2. CD155 expression in melanoma cells inversely correlates with the TIGIT/CD226 expression ratio in TiNKs.

Human organoids stand at the forefront of basic and translational research, providing experimentally tractable systems to study human development and disease. These stem cell-derived, in vitro cultures can generate a multitude of tissue and organ types, including distinct brain regions and sensory systems. Neural organoid systems have provided fundamental insights into molecular mechanisms governing cell fate specification and neural circuit assembly and serve as promising tools for drug discovery and understanding disease pathogenesis. In this review, we discuss several human neural organoid systems, how they are generated, advances in 3D imaging and bioengineering, and the impact of organoid studies on our understanding of the human nervous system.

It is increasingly clear that the nectin family and its immunoreceptors shape the immune response to cancer through several pathways. Yet, even as antibodies against TIGIT, CD96, and CD112R advance into clinical development, biological and therapeutic questions remain unanswered. Here, we review recent progress, prospects, and challenges to understanding and tapping this family in cancer immunotherapy.

In the original article, the code used to estimate the meta-regression models (of WTP for coastal marsh habitat changes) erroneously included the natural log of nominal rather than real income as an independent variable.

Non‐market goods can be measured on cardinal or relative scales. Consider a marsh of 200 acres, of which 20 acres would be affected by a policy. The same affected area can be measured in cardinal terms (20 acres) or as a relative proportion (10% of the marsh). When relative units such as percentages are a scalar transformation of cardinal units, the units of measurement used for modeling are often inconsequential for single‐site econometric and welfare analysis. However, this seemingly inconsequential transformation can have significant implications for benefit transfer across sites—a simple observation that remains unacknowledged by the literature. This article provides a theoretical and empirical evaluation of variable measurement conventions within benefit transfer, deriving conditions under which different types of measurement scales are expected to enhance validity and reliability. Theoretical results are illustrated using an application of discrete choice experiments to coastal flood adaptation in two Connecticut (United States) communities. Empirical findings validate expectations from the theoretical model, suggesting that transfers over goods measured in relative units may often outperform transfers over goods measured in cardinal units. These findings imply that the outcome of benefit transfer convergent validity tests may hinge on whether goods are measured in cardinal or relative units.

Despite advancements in targeting the immune checkpoints program cell death protein 1 (PD-1), programmed death ligand 1 (PD-L1), and cytotoxic T lymphocyte–associated protein 4 (CTLA-4) for cancer immunotherapy, a large number of patients and cancer types remain unresponsive. Current immunotherapies focus on modulating an antitumor immune response by directly or indirectly expanding antitumor CD8 T cells. A complementary strategy might involve inhibition of Tregs that otherwise suppress antitumor immune responses. Here, we sought to identify functional immune molecules preferentially expressed on tumor-infiltrating Tregs. Using genome-wide RNA-Seq analysis of purified Tregs sorted from multiple human cancer types, we identified a conserved Treg immune checkpoint signature. Using immunocompetent murine tumor models, we found that antibody-mediated depletion of 4-1BB–expressing cells (4-1BB is also known as TNFRSF9 or CD137) decreased tumor growth without negatively affecting CD8 T cell function. Furthermore, we found that the immune checkpoint 4-1BB had a high selectivity for human tumor Tregs and was associated with worse survival outcomes in patients with multiple tumor types. Thus, antibody-mediated depletion of 4-1BB–expressing Tregs represents a strategy with potential activity across cancer types.

Many animals depend on the sense of vision for survival. In eumetazoans, vision requires specialized, light-sensitive cells called photoreceptors. Light reaches the photoreceptors and triggers the excitation of light-detecting proteins called opsins. Here, we describe the story of visual opsin evolution from the ancestral bilaterian to the extant vertebrate lineages. We explain the mechanisms determining color vision of extant vertebrates, focusing on opsin gene losses, duplications, and the expression regulation of vertebrate opsins. We describe the sequence variation both within and between species that has tweaked the sensitivities of opsin proteins towards different wavelengths of light. We provide an extensive resource of wavelength sensitivities and mutations that have diverged light sensitivity in many vertebrate species and predict how these mutations were accumulated in each lineage based on parsimony. We suggest possible natural and sexual selection mechanisms underlying these spectral differences. Understanding how molecular changes allow for functional adaptation of animals to different environments is a major goal in the field, and therefore identifying mutations affecting vision and their relationship to photic selection pressures is imperative. The goal of this review is to provide a comprehensive overview of our current understanding of opsin evolution in vertebrates.

Development is often driven by signaling and lineage-specific cues, yielding highly uniform and reproducible outcomes. Development also involves mechanisms that generate noise in gene expression and random patterns across tissues. Cells sometimes randomly choose between two or more cell fates in a mechanism called stochastic cell fate specification. This process diversifies cell types in otherwise homogenous tissues. Stochastic mechanisms have been extensively studied in prokaryotes where noisy gene activation plays a pivotal role in controlling cell fates. In eukaryotes, transcriptional repression stochastically limits gene expression to generate random patterns and specify cell fates. Here, we review our current understanding of repressive mechanisms that produce random patterns of gene expression and cell fates in flies, plants, mice, and humans.

Stochastic mechanisms diversify cell fates during development. How cells randomly choose between two or more fates remains poorly understood. In the Drosophila eye, the random mosaic of two R7 photoreceptor subtypes is determined by expression of the transcription factor Spineless (Ss). Here, we investigated how cis-regulatory elements and trans factors regulate nascent transcriptional activity and chromatin compaction at the ss gene locus during R7 development. We find that the ss locus is in a compact state in undifferentiated cells. An early enhancer drives ss transcription in all R7 precursors to open the ss locus. In differentiating cells, transcription ceases and the ss locus stochastically remains open or compacts. In SsON R7s, ss is open and competent for activation by a late enhancer, whereas in SsOFF R7s, ss is compact and repression prevents expression. Our results suggest that a temporally dynamic antagonism, in which transcription drives decompaction and then compaction represses transcription, controls stochastic cell fate specification.

This article discusses prospects and challenges related to the use of meta-regression models (MRMs) for ecosystem service benefit transfer, with an emphasis on validity criteria and post-estimation procedures given sparse attention in the ecosystem services literature. We illustrate these topics using a meta-analysis of willingness to pay for water quality changes that support aquatic ecosystem services and the application of this model to estimate water quality benefits under alternative riparian buffer restoration scenarios in New Hampshire's Great Bay Watershed. These illustrations highlight the advantages of MRM benefit transfers, together with the challenges and data needs encountered when quantifying ecosystem service values.

Co-inhibitory immune receptors can contribute to T cell dysfunction in patients with cancer1,2. Blocking antibodies against cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1) partially reverse this effect and are becoming standard of care in an increasing number of malignancies3. However, many of the other axes by which tumours become inhospitable to T cells are not fully understood. Here we report that V-domain immunoglobulin suppressor of T cell activation (VISTA) engages and suppresses T cells selectively at acidic pH such as that found in tumour microenvironments. Multiple histidine residues along the rim of the VISTA extracellular domain mediate binding to the adhesion and co-inhibitory receptor P-selectin glycoprotein ligand-1 (PSGL-1). Antibodies engineered to selectively bind and block this interaction in acidic environments were sufficient to reverse VISTA-mediated immune suppression in vivo. These findings identify a mechanism by which VISTA may engender resistance to anti-tumour immune responses, as well as an unexpectedly determinative role for pH in immune co-receptor engagement. V-domain immunoglobulin suppressor of T cell activation (VISTA) selectively engages P-selectin glycoprotein ligand-1 (PSGL-1) and suppresses T cells at acidic pH similar to those in tumour microenvironments, thereby mediating resistance to anti-tumour immune responses.

Prioritising investments to minimise or mitigate natural hazards such as wildfires and storms is of increasing importance to hazard managers. Prioritisation of this type can be strengthened by considering benefit and cost impacts. To evaluate benefits and costs, managers require an understanding of both the tangible economic benefits and costs of mitigation decisions, and the often intangible values associated with environmental, social and health-related outcomes. We review the state of non-market valuation studies that provide monetary equivalent estimates for the intangible benefits and costs that can be affected by natural hazard events or their mitigation. We discuss whether managers can usefully call upon these available estimates, with a view to using the benefit transfer approach to include non-market values in economic decision frameworks. Additional context-specific non-market valuation studies are required to provide a more accurate selection of value estimates for natural hazard decision making. Decision making would benefit from considering these values explicitly in prioritising natural hazard investments.

Obtaining valid stated preference welfare estimates for changes in biophysical systems requires identification of the ecological endpoints valued by respondents. Challenges for scenario design can occur if endpoints differ across respondents, because it may be infeasible to provide scenario information on all possible endpoints. We explore an approach to choice experiments that tailors attributes to empirically identified population groups. Results suggest that different endpoints are relevant to different groups, and that one-size-fits-all scenarios common in the literature may not enable valid welfare estimation for all groups. These findings suggest that endpoint heterogeneity should be considered when designing valuation studies.

CD96 is a novel target for cancer immunotherapy shown to regulate NK cell effector function and metastasis. Here, we demonstrated that blocking CD96 suppressed primary tumor growth in a number of experimental mouse tumor models in a CD8+ T cell–dependent manner. DNAM-1/CD226, Batf3, IL12p35, and IFNγ were also critical, and CD96-deficient CD8+ T cells promoted greater tumor control than CD96-sufficient CD8+ T cells. The antitumor activity of anti-CD96 therapy was independent of Fc-mediated effector function and was more effective in dual combination with blockade of a number of immune checkpoints, including PD-1, PD-L1, TIGIT, and CTLA-4. We consistently observed coexpression of PD-1 with CD96 on CD8+ T lymphocytes in tumor-infiltrating leukocytes both in mouse and human cancers using mRNA analysis, flow cytometry, and multiplex IHF. The combination of anti-CD96 with anti–PD-1 increased the percentage of IFNγ-expressing CD8+ T lymphocytes. Addition of anti-CD96 to anti–PD-1 and anti-TIGIT resulted in superior antitumor responses, regardless of the ability of the anti-TIGIT isotype to engage FcR. The optimal triple combination was also dependent upon CD8+ T cells and IFNγ. Overall, these data demonstrate that CD96 is an immune checkpoint on CD8+ T cells and that blocking CD96 in combination with other immune-checkpoint inhibitors is a strategy to enhance T-cell activity and suppress tumor growth.

Trichromacy is unique to primates among mammals, enabled by blue (short/S), green (medium/M), and red (long/L) cones. In humans and Old World monkeys, cones make a poorly understood choice between M and L cone subtype fates. To determine mechanisms specifying M and L cones, we developed an approach to visualize expression of the highly similarM- andL-opsinmRNAs.M-opsin, but notL-opsin, was observed during early human eye development, suggesting that M cones are generated before L cones. In adult human tissue, the early-developing central retina contained a mix of M and L cones compared to the late-developing peripheral region, which contained a high proportion of L cones. Retinoic acid (RA)-synthesizing enzymes are highly expressed early in retinal development. High RA signaling early was sufficient to promote M cone fate and suppress L cone fate in retinal organoids. Across a human population sample, natural variation in the ratios of M and L cone subtypes was associated with a noncoding polymorphism in theNR2F2gene, a mediator of RA signaling. Our data suggest that RA promotes M cone fate early in development to generate the pattern of M and L cones across the human retina.

Cones are the color-detecting photoreceptors of the vertebrate eye. Cones are specialized into subtypes whose functions are determined by the expression of color-sensitive opsin proteins. Organisms differ greatly in the number and patterning of cone subtypes. Despite these differences, thyroid hormone is an important regulator of opsin expression in most vertebrates. In this chapter, we outline how the timing of thyroid hormone signaling controls cone subtype fates during retinal development. We first examine our current understanding of cone subtype specification in model organisms and then describe advances in human stem cell-derived organoid technology that identified mechanisms controlling development of the human retina.

Stem cells have the unique ability to undergo asymmetric division which produces two daughter cells that are genetically identical, but commit to different cell fates. The loss of this balanced asymmetric outcome can lead to many diseases, including cancer and tissue dystrophy. Understanding this tightly regulated process is crucial in developing methods to treat these abnormalities. Here, we report that produced from aDrosophilafemale germline stem cell asymmetric division, the two daughter cells differentially inherit histones at key genes related to either maintaining the stem cell state or promoting differentiation, but not at constitutively active or silenced genes. We combined histone labeling with DNA Oligopaints to distinguish old versus new histone distribution and visualize their inheritance patterns at single-gene resolution in asymmetrically dividing cellsin vivo. This strategy can be widely applied to other biological contexts involving cell fate establishment during development or tissue homeostasis in multicellular organisms.

Purpose: Natural killer (NK) cells play a critical role in tumor immunosurveillance. Multiple activating and inhibitory receptors (IR) regulate NK-cell–mediated tumor control. The IR T-cell immunoglobulin and ITIM domain (TIGIT) and its counter-receptor CD226 exert opposite effects on NK-cell–mediated tumor reactivity. Experimental Design: We evaluated the frequency, phenotype, and functions of NK cells freshly isolated from healthy donors and patients with melanoma with multiparameter flow cytometry. We assessed TIGIT and CD226 cell surface expression and internalization upon binding to CD155. We evaluated the role of IL15 and TIGIT blockade in increasing NK-cell–mediated cytotoxicity in vitro and in two mouse models. Results: NK cells are present at low frequencies in metastatic melanoma, are dysfunctional, and downregulate both TIGIT and CD226 expression. As compared with TIGIT− NK cells, TIGIT+ NK cells exhibit higher cytotoxic capacity and maturation, but paradoxically lower cytotoxicity against CD155+ MHC class I–deficient melanoma cells. Membrane bound CD155 triggers CD226 internalization and degradation, resulting in decreased NK-cell–mediated tumor reactivity. IL15 increases TIGIT and CD226 gene expression by tumor-infiltrating NK cells (TiNKs) and, together with TIGIT blockade, increases NK-cell–mediated melanoma cytotoxicity in vitro and decreases tumor metastasis in two mouse melanoma models. Specific deletion of TIGIT on transferred NK cells enhances the antimetastatic activity of IL15, while CD226 blockade decreases the effects of IL15 and TIGIT blockade. Conclusions: Our findings support the development of novel combinatorial immunotherapy with IL15 and TIGIT blockade to promote NK-cell–mediated destruction of MHC class I–deficient melanoma, which are refractory to CD8+ T-cell–mediated immunity. See related commentary by Pietra et al., p. 5274

Choice experiments addressing outcome uncertainty (OU) typically reframe continuous probability densities for each risky outcome into two discrete categories, each with a single probability of occurrence. The implications of this simplification for welfare estimation are unknown. This article evaluates the convergent validity of willingness-to-pay (WTP) estimates from a more accurate multiple-outcome treatment of OU, compared to the two-outcome approach. Results for a case study of coastal flood adaptation in Connecticut, United States, suggest that higher-resolution OU treatments increase choice complexity but can provide additional information on risk preferences and WTP. This tradeoff highlights challenges facing the valuation of uncertain outcomes.

There is a growing movement in government, environmental non-governmental organizations and the private sector to include ecosystem services in decision making. Adding ecosystem services into assessments implies measuring how much a change in ecological conditions affects people, social benefit, or value to society. Despite consensus around the general merit of accounting for ecosystem services, systematic guidance on what to measure and how is lacking. Current ecosystem services assessments often resort to biophysical proxies (e.g., area of wetland in a floodplain) or even disregard services that seem difficult to measure. Valuation, an important tool for assessing trade-offs and comparing outcomes, is also frequently omitted due to lack of data on social preferences, lack of expertise with valuation methods, or mistrust of valuation methods for non-market services. To address these shortcomings, we propose the use of a new type of indicator that explicitly reflects an ecosystem’s capacity to provide benefits to society, ensuring that ecosystem services assessments measure outcomes that are demonstrably and directly relevant to human welfare. We call these Benefit-relevant indicators (BRIs) and describe a process for developing them using causal chains that link management decisions through ecological responses to effects on human well-being. BRIs identify what is valued and by whom, but stop short of valuation. A BRI for the ability of wetlands to ameliorate flooding would connect measures of the quantity and quality of wetland in a floodplain, as affected by wetlands management decisions, to the number of people or properties downstream that are vulnerable to flooding. BRIs can support monetary or non-monetary valuation, but are particularly useful when valuation will not be conducted; in such cases they serve as stand-alone measures of “what is valued” by particular beneficiaries. BRIs are valid measures of ecosystem services in that they are directly linked to human well-being. Flexibility in the development of BRIs helps to ensure that they are broadly applicable across practitioner and stakeholder communities and decision contexts.

Pluripotent stem cells (PSCs), which include human embryonic stem cells (hESCs) and induced pluripotent stem cell (iPSC), have been used to study development of disease processes, and as potential therapies in multiple organ systems. In recent years, there has been increasing interest in the use of PSC-based transplantation to treat disorders of the retina in which retinal cells have been functionally damaged or lost through degeneration. The retina, which consists of neuronal tissue, provides an excellent system to test the therapeutic utility of PSC-based transplantation due to its accessibility and the availability of high-resolution imaging technology to evaluate effects. Preclinical trials in animal models of retinal diseases have shown improvement in visual outcomes following subretinal transplantation of PSC-derived photoreceptors or retinal pigment epithelium (RPE) cells. This review focuses on preclinical studies and clinical trials exploring the use of PSCs for retinal diseases. To date, several phase I/II clinical trials in patients with age-related macular degeneration (AMD) and Stargardt disease (STGD1) have demonstrated the safety and feasibility of PSC-derived RPE transplantation. Additional phase I/II clinical trials using PSC-derived RPE or photoreceptor cells for the treatment of AMD, STGD1, and also retinitis pigmentosa (RP) are currently in the pipeline. As this field continues to evolve, additional technologies may enhance PSC-derived cell transplantation through gene-editing of autologous cells, transplantation of more complex cellular structures such as organoids, and monitoring of transplanted cells through novel imaging technologies.

There is growing demand for information regarding the impacts of decisions on ecosystem services and human benefits. Despite the large and growing quantity of published ecosystem services research, there remains a substantial gap between this research and the information required to support decisions. Research often provides models and tools that do not fully link social and ecological systems; are too complex, specialized, and costly to use; and are targeted to outcomes that differ from those needed by decision makers. Decision makers require cost-effective, straightforward, transferable, scalable, meaningful, and defensible methods that can be readily understood. We provide illustrative examples of these gaps between research and practice and describe how researchers can make their work relevant to decision makers by using Benefit Relevant Indicators (BRIs) and choosing models appropriate for particular decision contexts. We use examples primarily from the United States, including cases that illustrate varying degrees of success in closing these gaps. We include a discussion of the challenges and opportunities researchers face in adapting their work to meet the needs of practitioners.

Seafood species vary in their health benefits (e.g., from omega-3 fatty acids) and risks (e.g., from methylmercury or polychlorobiphenyls). Reflecting these risks and benefits, multiple public and private organizations offer guidance to consumers on seafood consumption. The effect of this guidance is unknown; previous literature has been unable to disentangle the effects of messages with differing health information, provided by different sources, on demand for different types of seafood. The result is ambiguity regarding the drivers of observed changes in seafood demand. This study investigates the effect of health risk and benefit information on preferences for wild and farmed salmon and swordfish, three species targeted by consumer guidance. The analysis applies an experimental auction with seafood consumers informed by a Bayesian risk-learning model. The model provides a systematic way to disentangle effects on seafood demand, for example, by evaluating whether changes in demand for different species are due to information content or source. Using this approach, we test the effect of guidance provided by four different public and private groups in the United States. Difference-in-difference tests find no impact of health benefit information regardless of source or message, but find multiple effects of health risk information that vary across different types of guidance. These findings suggest that current guidance does not improve consumers’ ability to balance health risks and benefits. We also identify potential avenues to improve the efficacy of this guidance.

Diversification of neuronal subtypes often requires stochastic gene regulatory mechanisms. How stochastically expressed transcription factors interact with other regulators in gene networks to specify cell fates is poorly understood. The random mosaic of color-detecting R7 photoreceptor subtypes inDrosophilais controlled by the stochastic on/off expression of the transcription factor Spineless (Ss). In SsONR7s, Ss induces expression of Rhodopsin 4 (Rh4), whereas in SsOFFR7s, the absence of Ss allows expression of Rhodopsin 3 (Rh3). Here, we find that the transcription factor Runt, which is initially expressed in all R7s, activates expression of Spineless in a random subset of R7s. Later, as R7s develop, Ss negatively feeds back onto Runt to prevent repression of Rh4 and ensure proper fate specification. Together, stereotyped and stochastic regulatory inputs are integrated into feedforward and feedback mechanisms to control cell fate.

© 2019 Australasian Agricultural and Resource Economics Society Inc. In nonmarket valuation, practitioners must choose a format for the valuation questions. A common approach in discrete choice experiments is the ‘pick-one’ format, often with two alternative policy proposals and a status quo from which the respondent selects. Other proposed formats, include best-worst elicitation, where respondents are asked to indicate their most and least favoured alternative from a set. Although best-worst formats can offer efficiency in data collection, they can also lead to responses that are difficult to reconcile with neoclassical welfare estimation. The current article explores methodological issues surrounding the use of pick-one versus best-worst data for nonmarket valuation, focusing on framing and status quo effects that may occur within three-alternative discrete choice experiments. We illustrate these issues using a case study of surplus groundwater use from Western Australian mining. Results identify concerns that may render best-worst data unsuitable for welfare estimation, including a prevalence of serial choices in which the status quo is universally chosen as the worst alternative, rendering part of the choice process deterministic. Asymmetry of preferences and serial choices can be obscured when models are estimated using ‘naively’ pooled best-worst data. Results suggest that caution is warranted when using best-worst data for valuation, even when pooled results appear satisfactory.

The preservation of salt marshes under rapid sea-level rise (SLR) typically requires the conservation of marsh transgression zones—undeveloped uplands onto which marshes can migrate. Optimal planning for conservation of this type requires information on the expected benefit of marsh conservation and the cost of land suitable for marsh migration in particular areas. While information is available on marsh benefits within the literature, prior research provides little insight on associated land conservation costs. The coastal hedonic pricing literature focuses primarily on developed land, and there are no models designed to predict the cost of conserving land suitable for marsh migration. This paper develops a hedonic property value model to predict cost and explore price patterns associated with purchases of undeveloped land suitable for salt marsh migration under SLR. The model is illustrated using a case study from the Eastern Shore of Virginia, with a dataset consisting of open-market sales of undeveloped land from 2014 to 2017. Particular attention is paid to characteristics that determine marsh migration potential such as coastal distance, elevation and connectivity. Results demonstrate the insight for conservation planning that can be provided by models of this type and the errors associated with the use of simplified proxies to predict conservation costs of land suitable for marsh migration.

Stated preference scenarios often describe outcomes to be valued in terms of intermediate biophysical processes or ecosystem services with indirect utility effects, rather than in terms of final, directly welfare‐relevant consequences. This article evaluates whether valid welfare estimates can emerge from this practice. We begin with a theoretical model demonstrating conditions under which stated preference scenarios that include intermediate outcomes will elicit welfare estimates identical to those from parallel scenarios that include associated final outcomes (i.e., convergent validity will hold). The model demonstrates that a necessary condition for convergent validity is the ability of respondents to correctly predict biophysical production functions linking intermediate to final outcomes. Hypotheses from the theoretical model are then evaluated empirically using an application of choice experiments to migratory fish restoration in the U.S. state of Rhode Island. Empirical results are mixed but generally reject convergent validity; welfare estimates are not robust to the use of an intermediate outcome in lieu of a related final outcome in stated preference scenarios, as predicted by theory. Results of the analysis suggest that greater attention should be given to the reliability of welfare estimation when final outcomes cannot be quantified.

This paper evaluates the common practice of generic mapping in stated preference valuation, in which identical policy area maps are shown to all respondents. This is compared to a more information-intensive alternative in which individualized maps identify the location of each respondent’s home relative to policy effects. The evaluation is grounded in a theoretical model clarifying the impact of individualized spatial information on preferences for non-market outcomes. The model is illustrated using an application of choice experiments to riparian restoration in coastal Maine. Results characterize valuation contexts for which valid preference elicitation likely requires the provision of individualized spatial information.

The activating receptor CD226 is expressed on lymphocytes, monocytes, and platelets and promotes anti-tumor immunity in pre-clinical models. Here, we examined the role of CD226 in the function of tumor-infiltrating lymphocytes (TILs) and resistance to immunotherapy. In murine tumors, a large proportion of CD8+ TILs had decreased surface expression of CD226 and exhibited features of dysfunction, whereas CD226hi TILs were highly functional. This correlation was seen also in TILs isolated from HNSCC patients. Mutation of CD226 at tyrosine 319 (Y319) led to increased CD226 surface expression, enhanced anti-tumor immunity and improved efficacy of immune checkpoint blockade (ICB). Mechanistically, tumor-derived CD155, the ligand for CD226, initiated phosphorylation of Y319 by Src kinases, thereby enabling ubiquitination of CD226 by CBL-B, internalization, and proteasomal degradation. In pre-treatment samples from melanoma patients, CD226+CD8+ T cells correlated with improved progression-free survival following ICB. Our findings argue for the development of therapies aimed at maintaining the expression of CD226.

Summary Homologous chromosomes colocalize to regulate gene expression in processes including genomic imprinting, X-inactivation, and transvection. In Drosophila, homologous chromosomes pair throughout development, promoting transvection. The “button” model of pairing proposes that specific regions along chromosomes pair with high affinity. Here, we identify buttons interspersed across the fly genome that pair with their homologous sequences, even when relocated to multiple positions in the genome. A majority of transgenes that span a full topologically associating domain (TAD) function as buttons, but not all buttons contain TADs. Additionally, buttons are enriched for insulator protein clusters. Fragments of buttons do not pair, suggesting that combinations of elements within a button are required for pairing. Pairing is necessary but not sufficient for transvection. Additionally, pairing and transvection are stronger in some cell types than in others, suggesting that pairing strength regulates transvection efficiency between cell types. Thus, buttons pair homologous chromosomes to facilitate cell-type-specific interchromosomal gene regulation.

INTRODUCTION: Cone photoreceptors in the human retina enable daytime, color, and high-acuity vision. The three subtypes of human cones are defined by the visual pigment that they express: blue-opsin (short wavelength; S), green-opsin (medium wavelength; M), or red-opsin (long wavelength; L). Mutations that affect opsin expression or function cause various forms of color blindness and retinal degeneration. RATIONALE: Our current understanding of the vertebrate eye has been derived primarily from the study of model organisms. We studied the human retina to understand the developmental mechanisms that generate the mosaic of mutually exclusive cone subtypes. Specification of human cones occurs in a two-step process. First, a decision occurs between S versus L/M cone fates. If the L/M fate is chosen, a subsequent choice is made between expression of L- or M-opsin. To determine the mechanism that controls the first decision between S and L/M cone fates, we studied human retinal organoids derived from stem cells. RESULTS: We found that human organoids and retinas have similar distributions, gene expression profiles, and morphologies of cone subtypes. During development, S cones are specified first, followed by L/M cones. This temporal switch from specification of S cones to generation of L/M cones is controlled by thyroid hormone (TH) signaling. In retinal organoids that lacked thyroid hormone receptor β (Thrβ), all cones developed into the S subtype. Thrβ binds with high affinity to triiodothyronine (T3), the more active form of TH, to regulate gene expression. We observed that addition of T3 early during development induced L/M fate in nearly all cones. Thus, TH signaling through Thrβ is necessary and sufficient to induce L/M cone fate and suppress S fate. TH exists largely in two states: thyroxine (T4), the most abundant circulating form of TH, and T3, which binds TH receptors with high affinity. We hypothesized that the retina itself could modulate TH levels to control subtype fates. We found that deiodinase 3 (DIO3), an enzyme that degrades both T3 and T4, was expressed early in organoid and retina development. Conversely, deiodinase 2 (DIO2), an enzyme that converts T4 to active T3, as well as TH carriers and transporters, were expressed later in development. Temporally dynamic expression of TH-degrading and -activating proteins supports a model in which the retina itself controls TH levels, ensuring low TH signaling early to specify S cones and high TH signaling later in development to produce L/M cones. CONCLUSION: Studies of model organisms and human epidemiology often generate hypotheses about human biology that cannot be studied in humans. Organoids provide a system to determine the mechanisms of human development, enabling direct testing of hypotheses in developing human tissue. Our studies identify temporal regulation of TH signaling as a mechanism that controls cone subtype specification in humans. Consistent with our findings, preterm human infants with low T3 and T4 have an increased incidence of color vision defects. Moreover, our identification of a mechanism that generates one cone subtype while suppressing the other, coupled with successful transplantation and incorporation of stem cell-derived photoreceptors in mice, suggests that the promise of therapies to treat human diseases such as color blindness, retinitis pigmentosa, and macular degeneration will be achieved in the near future. ■, Graphical Abstract Temporally regulated TH signaling specifies cone subtypes. (A) Embryonic stem cell-derived human retinal organoids [wild type (WT)] generate S and L/M cones. Blue, S-opsin; green, L/M-opsin. (B) Organoids that lack thyroid hormone receptor β (Thrβ KO) generate all S cones. (C) Early activation of TH signaling (WT + T3) specifies nearly all L/M cones. (D) TH-degrading enzymes (such as DIO3) expressed early in development lower TH and promote S fate, whereas TH-activating regulators (such as DIO2) expressed later promote L/M fate., Summary The mechanisms underlying specification of neuronal subtypes within the human nervous system are largely unknown. The blue (S), green (M), and red (L) cones of the retina enable high-acuity daytime and color vision. To determine the mechanism that controls S versus L/M fates, we studied the differentiation of human retinal organoids. Organoids and retinas have similar distributions, expression profiles, and morphologies of cone subtypes. S cones are specified first, followed by L/M cones, and thyroid hormone signaling controls this temporal switch. Dynamic expression of thyroid hormone–degrading and –activating proteins within the retina ensures low signaling early to specify S cones and high signaling late to produce L/M cones. This work establishes organoids as a model for determining mechanisms of human development with promising utility for therapeutics and vision repair.