The Molecular Basis for Specificity at the Level of the Protein Kinase a Catalytic Subunit

Assembly of multi enzyme complexes at subcellular localizations by anchoring- and scaffolding proteins represents a pivotal mechanism for achieving spatiotemporal regulation of cellular signaling after hormone receptor targeting [for review, see (1)]. In the 3' 5'-cyclic adenosine monophosphate (cAMP) dependent protein kinase (PKA) signaling pathway it is generally accepted that specificity is secured at several levels. This includes at the first level stimulation of receptors coupled to heterotrimeric G proteins which through stimulation of adenylyl cyclase (AC) forms the second messenger cAMP. Cyclic AMP has several receptors including PKA. PKA is a tetrameric holoenzyme consisting of a regulatory (R) subunit dimer and two catalytic (C) subunits. The R subunit is the receptor for cAMP and compartmentalizes cAMP signals through binding to cell and tissue-specifically expressed A kinase anchoring proteins (AKAPs). The current dogma tells that in the presence of cAMP, PKA dissociates into an R subunit dimer and two C subunits which are free to phosphorylate relevant substrates in the cytosol and nucleus. The release of the C subunit has raised the question how specificity of the cAMP and PKA signaling pathway is maintained when the C subunit no longer is attached to the R subunit-AKAP complex. An increasing body of evidence points toward a regulatory role of the cAMP and PKA signaling pathway by targeting the C subunits to various C subunit binding proteins in the cytosol and nucleus. Moreover, recent identification of isoform specific amino acid sequences, motifs and three dimensional structures have together provided new insight into how PKA at the level of the C subunit may act in a highly isoform-specific fashion. Here we discuss recent understanding of specificity of the cAMP and PKA signaling pathway based on C subunit subcellular targeting as well as evolution of the C subunit structure that may contribute to the dynamic regulation of C subunit activity.

Not all Anchors Weigh Equally

The anchoring bias is a reliable effect wherein a person's judgments are affected by initially presented information, but it is unknown specifically why this effect occurs. Research examining this bias suggests that elements of both numeric and semantic priming may be involved. To examine this, the present research used a phenomenon wherein people treat numeric information presented differently in Arabic numeral or verbal formats. We presented participants with one of many forms of an anchor that represented the same value (e.g., twelve hundred or 1,200). Thus, we could examine how a concept's meaning and its absolute numeric value affect anchoring. Experiments 1 and 2 showed that people respond to Arabic and verbal anchors differently. Experiment 3 showed that these differences occurred largely because people tend to think of numbers in digit format. This suggests that one's conceptual understanding of the anchored information matters more than its strict numeric value.

Small Cues Change Savings Choices

We present evidence from randomized field experiments that 401(k) savings choices are significantly affected by one- to two-sentence anchoring, goal-setting, or savings threshold cues embedded in emails sent to employees about their 401(k) plan. Even though these cues contain little to no marginal information, cues that make high savings rates salient increased 401(k) contribution rates by up to 2.9% of income in a pay period, and cues that make low savings rates salient decreased 401(k) contribution rates by up to 1.4% of income in a pay period. Cue effects persist between two months and a year after the email.

Anchors aweigh: The impact of overlearning on entrenchment effects in statistical learning

Previous research has revealed that when learners encounter multiple artificial languages in succession only the first is learned, unless there are contextual cues correlating with the change in structure or if exposure to the second language is protracted. These experiments provided a fixed amount of exposure irrespective of when learning occurred. Here, the authors presented learners with 2 consecutive artificial languages testing learning after each minute of familiarization. In Experiment 1, learners received fixed input, and the authors replicated the primacy effect. In Experiment 2, learners advanced to the second language immediately following robust learning of the first language (thereby limiting additional exposure past the point of learning). Remarkably, learners tended to acquire and retain both languages, although contextual cues did not boost performance further. Notably, there was no correlation between performance on this task and a flanker task that measured inhibitory control. Overall, the findings suggest that anchoring effects in statistical learning may be because of overlearning. We speculate that learners may reduce their attention to the input once they achieve a low level of estimation uncertainty. (PsycINFO Database Record

Outcome measures in neuromuscular disease: is the world still flat?

Valid, responsive, and meaningful outcome measures for the measurement of the impairment, activity limitations, and quality of life in patients with neuromuscular disease are crucial to identify the natural history of disease and benefits of therapy in clinical practice and trials. Although understanding of many aspects of neuromuscular diseases has advanced dramatically, the development of outcome measures has received less attention. The scales developed from Rasch theory by the PeriNomS Group represent the biggest significant shift in thought in neuromuscular outcome measures for decades. There remain problems with many of them, and further developments are required. However, incorporating them into our outcome sets for daily use and in clinical trials will lead to the more efficient capture of meaningful change and will result in better assessment of individuals and groups of patients in both clinical trials and neurological practice.

A Perspective on Consumers 3.0: They Are Not Better Decision-Makers than Previous Generations

This perspective article builds upon the theory of local thinking in interpretation and prediction of consumer behavior in a contemporary world of information overload. It is shown that even informed and socially and environmentally responsible consumers (consumers 3.0) exhibit selective recall, limited attention, and bounded search in the perception and interpretation of price and quality of purchases. Their decisions fall into local cognitive frames, which specifically focus attention only on a narrow structure and content of the choice. The cognitive frames can be established by recent or regular purchases, but also extreme or primary purchase experiences. The article includes a short conceptual review of car, food, clothing, insurance, drugs, paintings, and other product purchases showing that the local cognitive frames often lead to bad bargains across various sectors. The article presents several suggestions for future research.

Spatial Rearrangement and Mobility Heterogeneity of an Anionic Lipid Monolayer Induced by the Anchoring of Cationic Semiflexible Polymer Chains

We use Monte Carlo simulations to investigate the interactions between cationic semiflexible polymer chains and a model fluid lipid monolayer composed of charge-neutral phosphatidyl-choline (PC), tetravalent anionic phosphatidylinositol 4,5-bisphosphate (PIP₂), and univalent anionic phosphatidylserine (PS) lipids. In particular, we explore how chain rigidity and polymer concentration influence the spatial rearrangement and mobility heterogeneity of the monolayer under the conditions where the cationic polymers anchor on the monolayer. We find that the anchored cationic polymers only sequester the tetravalent PIP₂ lipids at low polymer concentrations, where the interaction strength between the polymers and the monolayer exhibits a non-monotonic dependence on the degree of chain rigidity. Specifically, maximal anchoring occurs at low polymer concentrations, when the polymer chains have an intermediate degree of rigidity, for which the PIP₂ clustering becomes most enhanced and the mobility of the polymer/PIP₂ complexes becomes most reduced. On the other hand, at sufficiently high polymer concentrations, the anchoring strength decreases monotonically as the chains stiffen-a result that arises from the pronounced competitions among polymer chains. In this case, the flexible polymers can confine all PIP₂ lipids and further sequester the univalent PS lipids, whereas the stiffer polymers tend to partially dissociate from the monolayer and only sequester smaller PIP₂ clusters with greater mobilities. We further illustrate that the mobility gradient of the single PIP₂ lipids in the sequestered clusters is sensitively modulated by the cooperative effects between anchored segments of the polymers with different rigidities. Our work thus demonstrates that the rigidity and concentration of anchored polymers are both important parameters for tuning the regulation of anionic lipids.

Analogies, metaphors, and wondering about the future: Lay sense-making around synthetic meat

Drawing on social representations theory, we explore how the public make sense of the unfamiliar, taking as the example a novel technology: synthetic meat. Data from an online deliberation study and eighteen focus groups in Belgium, Portugal and the UK indicated that the various strategies of sense-making afforded different levels of critical thinking about synthetic meat. Anchoring to genetic modification, metaphors like 'Frankenfoods' and commonplaces like 'playing God' closed off debates around potential applications of synthetic meat, whereas asking factual and rhetorical questions about it, weighing up pragmatically its risks and benefits, and envisaging changing current mentalities or behaviours in order to adapt to scientific developments enabled a consideration of synthetic meat's possible implications for agriculture, environment, and society. We suggest that research on public understanding of technology should cultivate a climate of active thinking and should encourage questioning during the process of sense-making to try to reduce unhelpful anchoring.

Direct observation of molybdenum disulfide, MoS2, domains by using a liquid crystalline texture method

Because the properties of molybdenum disulfide (MoS2) are strongly influenced by the sizes and boundaries of its domains, the direct visualization of large-area MoS2 domains is one of the most important challenges in MoS2 research. In the current study, we developed a simple and rapid method to observe and determine the boundaries of MoS2 domains. The technique, which depends on observations of nematic liquid crystal textures on the MoS2 surface, does not damage the sample and is not limited by domain size. Thus, this approach should significantly aid not only efforts aimed at gaining an understanding of the relationships between grain boundaries and properties of MoS2 but also those focusing on how domain sizes are controlled during large-area synthesis.

Anchors weigh more than power: why absolute powerlessness liberates negotiators to achieve better outcomes

The current research shows that having no power can be better than having a little power. Negotiators prefer having some power (weak negotiation alternatives) to having no power (no alternatives). We challenge this belief that having any alternative is beneficial by demonstrating that weak alternatives create low anchors that reduce the value of first offers. In contrast, having no alternatives is liberating because there is no anchor to weigh down first offers. In our experiments, negotiators with no alternatives felt less powerful but made higher first offers and secured superior outcomes compared with negotiators who had weak alternatives. We established the role of anchoring through mediation by first offers and through moderation by showing that weak alternatives no longer led to worse outcomes when negotiators focused on a countervailing anchor or when negotiators faced an opponent with a strong alternative. These results demonstrate that anchors can have larger effects than feelings of power. Absolute powerlessness can be psychologically liberating.

Lightness perception in simple images: testing the anchoring rules

One approach toward understanding how vision computes surface lightness is to first determine what principles govern lightness in simple stimuli and then test whether these hold for more complex stimuli. Gilchrist (2006) proposed that in the simplest images that produce the experience of a surface (two surfaces differing in luminance that fill the entire visual field) lightness can be predicted based on two anchoring rules: the highest luminance rule and the area rule, plus a scale normalization. To test whether these anchoring rules hold when critical features of the stimuli are varied, we probed lightness in simple stimuli, painted onto the inside of hemispheric domes viewed under diffuse lighting. We find that although the highest luminance surface appears nearly white across a large variation in illumination (as predicted by the highest luminance rule), its lightness tends to increase as its luminance increases. This effect is small relative to the size of the overall luminance change. Further, we find that when the darker region fills more than half of the visual field, it appears to lighten with further increases in area but only if it is a single surface. Splitting the dark region into smaller sectors that cover an equal cumulative area diminishes or eliminates the area effect.

Mechanisms of otoconia and otolith development

BACKGROUND

Otoconia are bio-crystals that couple mechanic forces to the sensory hair cells in the utricle and saccule, a process essential for us to sense linear acceleration and gravity for the purpose of maintaining bodily balance. In fish, structurally similar bio-crystals called otoliths mediate both balance and hearing. Otoconia abnormalities are common and can cause vertigo and imbalance in humans. However, the molecular etiology of these illnesses is unknown, as investigators have only begun to identify genes important for otoconia formation in recent years.

RESULTS

To date, in-depth studies of selected mouse otoconial proteins have been performed, and about 75 zebrafish genes have been identified to be important for otolith development.

CONCLUSIONS

This review will summarize recent findings as well as compare otoconia and otolith development. It will provide an updated brief review of otoconial proteins along with an overview of the cells and cellular processes involved. While continued efforts are needed to thoroughly understand the molecular mechanisms underlying otoconia and otolith development, it is clear that the process involves a series of temporally and spatially specific events that are tightly coordinated by numerous proteins. Such knowledge will serve as the foundation to uncover the molecular causes of human otoconia-related disorders.

Mechanisms of otoconia and otolith development

BACKGROUND

Otoconia are bio-crystals that couple mechanic forces to the sensory hair cells in the utricle and saccule, a process essential for us to sense linear acceleration and gravity for the purpose of maintaining bodily balance. In fish, structurally similar bio-crystals called otoliths mediate both balance and hearing. Otoconia abnormalities are common and can cause vertigo and imbalance in humans. However, the molecular etiology of these illnesses is unknown, as investigators have only begun to identify genes important for otoconia formation in recent years.

RESULTS

To date, in-depth studies of selected mouse otoconial proteins have been performed, and about 75 zebrafish genes have been identified to be important for otolith development.

CONCLUSIONS

This review will summarize recent findings as well as compare otoconia and otolith development. It will provide an updated brief review of otoconial proteins along with an overview of the cells and cellular processes involved. While continued efforts are needed to thoroughly understand the molecular mechanisms underlying otoconia and otolith development, it is clear that the process involves a series of temporally and spatially specific events that are tightly coordinated by numerous proteins. Such knowledge will serve as the foundation to uncover the molecular causes of human otoconia-related disorders.

Lightness, brightness, and anchoring

The majority of work in lightness perception has evaluated the perception of lightness using flat, matte, two-dimensional surfaces. In such contexts, the amount of light reaching the eye contains a conflated mixture of the illuminant and surface lightness. A fundamental puzzle of lightness perception is understanding how it is possible to experience achromatic surfaces as specific achromatic shades in the face of this ambiguity. It has been argued that the perception of lightness in such contexts implies that the visual system imposes an "anchoring rule" whereby a specific relative luminance (the highest) serves as a fixed point in the mapping of image luminance onto the lightness scale ("white"). We conducted a series of experiments to explicitly test this assertion in contexts where this mapping seemed most unlikely-namely, low-contrast images viewed in dim illumination. Our results provide evidence that the computational ambiguity in mapping luminance onto lightness is reflected in perceptual experience. The perception of the highest luminance in a two-dimensional Mondrian display varied monotonically with its brightness, ranging from midgray to white. Similar scaling occurred for the lowest luminance and, by implication, all other luminance values. We conclude that the conflation between brightness and lightness in two-dimensional Mondrian displays is reflected in perception and find no support for the claim that any specific relative luminance value acts as a fixed anchor point in this mapping function.

Perceptions of water use

In a national online survey, 1,020 participants reported their perceptions of water use for household activities. When asked for the most effective strategy they could implement to conserve water in their lives, or what other Americans could do, most participants mentioned curtailment (e.g., taking shorter showers, turning off the water while brushing teeth) rather than efficiency improvements (e.g., replacing toilets, retrofitting washers). This contrasts with expert recommendations. Additionally, some participants are more likely to list curtailment actions for themselves, but list efficiency actions for other Americans. For a sample of 17 activities, participants underestimated water use by a factor of 2 on average, with large underestimates for high water-use activities. An additional ranking task showed poor discrimination of low vs. high embodied water content in food products. High numeracy scores, older age, and male sex were associated with more accurate perceptions of water use. Overall, perception of water use is more accurate than the perception of energy consumption and savings previously reported. Well-designed efforts to improve public understanding of household water use could pay large dividends for behavioral adaptation to temporary or long-term decreases in availability of fresh water.

The first-mover disadvantage: the folly of revealing compatible preferences

The current research establishes a first-mover disadvantage in negotiation. We propose that making the first offer in a negotiation will backfire when the sender reveals private information that an astute recipient can leverage to his or her advantage. In two experiments, we manipulated whether the first offer was purely distributive or revealed that the sender's preferences were compatible with the recipient's preferences (i.e., the negotiators wanted the same outcome on an issue). When first offers contained only distributive issues, the classic first-mover advantage occurred, and first offers predicted final prices. However, a first-mover disadvantage emerged when senders opened with offers that revealed compatible preferences. These effects were moderated by negotiators' social value orientation: Proself negotiators were more likely to take advantage of compatible information than were prosocial negotiators. Overall, the key factor that determined whether the first-mover advantage or disadvantage emerged was whether the offer revealed compatible preferences. These results demonstrate that first offers not only provide numerical value but also convey qualitative information.

SHORT-RUN SUBSIDIES AND LONG-RUN ADOPTION OF NEW HEALTH PRODUCTS: EVIDENCE FROM A FIELD EXPERIMENT

Short-run subsidies for health products are common in poor countries. How do they affect long-run adoption? A common fear among development practitioners is that one-off subsidies may negatively affect long-run adoption through reference-dependence: People might anchor around the subsidized price and be unwilling to pay more for the product later. But for experience goods, one-off subsidies could also boost long-run adoption through learning. This paper uses data from a two-stage randomized pricing experiment in Kenya to estimate the relative importance of these effects for a new, improved antimalarial bed net. Reduced form estimates show that a one-time subsidy has a positive impact on willingness to pay a year later inherit. To separately identify the learning and anchoring effects, we estimate a parsimonious experience-good model. Estimation results show a large, positive learning effect but no anchoring. We black then discuss the types of products and the contexts inherit for which these results may apply.

The remarkable robustness of the first-offer effect: across culture, power, and issues

The first-offer effect demonstrates that negotiators achieve better outcomes when making the first offer than when receiving it. The evidence, however, primarily derives from studies of Westerners without systematic power differences negotiating over one issue-contexts that may amplify the first-offer effect. Thus, the present research explored the effect across cultures, among negotiators varying in power, and in negotiations involving single and multiple issues. The first two studies showed that the first-offer effect remains remarkably robust across cultures and multi-issue negotiations. The final two studies demonstrated that low-power negotiators benefit from making the first offer across single- and multi-issue negotiations. The second and fourth studies used multi-issue negotiations with distributive, integrative, and compatible issues, allowing us to show that first offers operate through the distributive, not the integrative or compatible issues. Overall, these results reveal that moving first can benefit negotiators across many organizational and personal situations.

Depth effect on lightness revisited: The role of articulation, proximity and fields of illumination

The coplanar ratio principle proposes that when the luminance range in an image is larger than the canonical reflectance range of 30:1, the lightness of a target surface depends on the luminance ratio between that target and its adjacent coplanar neighbor (Gilchrist, 1980). This conclusion is based on experiments in which changes in the perceived target depth produced large changes in its perceived lightness without significantly altering the observers' retinal image. Using the same paradigm, we explored how this depth effect on lightness depends on display complexity (articulation), proximity of the target to its highest coplanar luminance and spatial distribution of fields of illumination. Importantly, our experiments allowed us to test differing predictions made by the anchoring theory (Gilchrist et al., 1999), the coplanar ratio principle, as well as other models. We report three main findings, generally consistent with anchoring theory predictions: (1) Articulation can substantially increase the depth effect. (2) Target lightness depends not on the adjacent luminance but on the highest coplanar luminance, irrespective of its position relative to the target. (3) When a plane contains multiple fields of illumination, target lightness depends on the highest luminance in its field of illumination, not on the highest coplanar luminance.

On the distinction of empathic and vicarious emotions

In the introduction to the special issue "The Neural Underpinnings of Vicarious Experience" the editors state that one "may feel embarrassed when witnessing another making a social faux pas". In our commentary we address this statement and ask whether this example introduces a vicarious or an empathic form of embarrassment. We elaborate commonalities and differences between these two forms of emotional experiences and discuss their underlying mechanisms. We suggest that both, vicarious and empathic emotions, originate from the simulation processes mirroring and mentalizing that depend on anchoring and adjustment. We claim the term "empathic emotion" to be reserved exclusively for incidents where perceivers and social targets have shared affective experience, whereas "vicarious emotion" offers a wider scope and also includes non-shared affective experiences. Both are supposed to be highly functional in social interactions.

Local computation of lightness on articulated surrounds

Lightness of a grey target on a uniform light (or dark) surround changes by articulating the surround (articulation effect). To elucidate the processing of lightness underlying the articulation effect, the present study introduced transparency over a dark surround and investigated its effects on lightness of the target. The transparency was produced by adding a contiguous external field to the dark surround while keeping local stimulus configuration constant. Results showed that the target lightness did not change on the articulated surround when a dark transparent filter was perceived over the target, although it did on the uniform surround. These results suggest that image decomposition into a transparent filter and an underlying surface does not necessarily change lightness of the surface if the surface is articulated. Moreover, the present study revealed that articulating the surround does not always enhance lightness contrast; it can reduce the contrast effect when the target luminance is not the highest within the surround. These findings are consistent with the theoretical view that lightness perception on articulated surfaces is determined locally within a spatially limited region, and they also place a constraint on how the luminance distribution within the limited region is scaled.

Preference Reversals in Decision Making Under Risk are Accompanied by Changes in Attention to Different Attributes

Recent work has shown that visual fixations reflect and influence trial-to-trial variability in people’s preferences between goods. Here we extend this principle to attribute weights during decision making under risk. We measured eye movements while people chose between two risky gambles or bid on a single gamble. Consistent with previous work, we found that people exhibited systematic preference reversals between choices and bids. For two gambles matched in expected value, people systematically chose the higher probability option but provided a higher bid for the option that offered the greater amount to win. This effect was accompanied by a shift in fixations of the two attributes, with people fixating on probabilities more during choices and on amounts more during bids. Our results suggest that the construction of value during decision making under risk depends on task context partly because the task differentially directs attention at probabilities vs. amounts. Since recent work demonstrates that neural correlates of value vary with visual fixations, our results also suggest testable hypotheses regarding how task context modulates the neural computation of value to generate preference reversals.

Public perceptions of energy consumption and savings

In a national online survey, 505 participants reported their perceptions of energy consumption and savings for a variety of household, transportation, and recycling activities. When asked for the most effective strategy they could implement to conserve energy, most participants mentioned curtailment (e.g., turning off lights, driving less) rather than efficiency improvements (e.g., installing more efficient light bulbs and appliances), in contrast to experts' recommendations. For a sample of 15 activities, participants underestimated energy use and savings by a factor of 2.8 on average, with small overestimates for low-energy activities and large underestimates for high-energy activities. Additional estimation and ranking tasks also yielded relatively flat functions for perceived energy use and savings. Across several tasks, participants with higher numeracy scores and stronger proenvironmental attitudes had more accurate perceptions. The serious deficiencies highlighted by these results suggest that well-designed efforts to improve the public's understanding of energy use and savings could pay large dividends.

In vitro biological activities of transmembrane superantigen staphylococcal enterotoxin A fusion protein

The bacterial superantigen staphylococcal enterotoxin A (SEA) stimulates T cells bearing certain TCR Vbeta domains when binding to MHC II molecules, and is a potent inducer of CTL activity and cytokine production. Antibody-targeted SEA such as C215 Fab-SEA and C242 Fab-SEA has been investigated for cancer therapy in recent years. We have previously reported significant tumor inhibition and prolonged survival time in tumor-bearing mice treated with a combination of both C215Fab-SEA and Ad IL-18 (Wang et al., Gene Therapy 8:542-550, 2001). In order to develop SEA as an universal biological preparation in cancer therapy, we first cloned a SEA gene from S. aureus (ATCC 13565) and a transmembrane (TM) sequence from a c- erb-b2 gene derived from human ovarian cancer cell line HO-8910, then generated a TM-SEA fusion gene by using the splice overlap extension method, and constructed the recombinant expression vector pET-28a-TM-SEA. Fusion protein TM-SEA was expressed in E. coli BL21(DE3)pLysS and purified by using the histidine tag in this vector. Purified TM-SEA spontaneously associated with cell membranes as detected by flow cytometry. TM-SEA stimulated the proliferation of both human PBLs and splenocytes derived from C57BL/6 (H-2b) mice in vitro. This study thus demonstrated a novel strategy for anchoring superantigen SEA onto the surfaces of tumor cells without any genetic manipulation.

Independent anchoring and assembly mechanisms of INAD signaling complexes in Drosophila photoreceptors

In Drosophila photoreceptors the multivalent PDZ protein INAD organizes the phototransduction cascade into a macromolecular signaling complex containing the effector PLC, the light-activated TRP channels, and a regulatory PKC. Previously, we showed that the subcellular localization of INAD signaling complexes is critical for signaling. Now we have examined how INAD complexes are anchored and assembled in photoreceptor cells. We find that trp mutants, or transgenic flies expressing inaD alleles that disrupt the interaction between INAD and TRP, cause the mislocalization of the entire transduction complex. The INAD-TRP interaction is not required for targeting but rather for anchoring of complexes, because INAD and TRP can be targeted independently of each other. We also show that, in addition to its scaffold role, INAD functions to preassemble transduction complexes. Preassembly of signaling complexes helps to ensure that transduction complexes with the appropriate composition end up in the proper location. This may be a general mechanism used by cells to target different signaling machinery to the pertinent subcellular location.