Mammalian cells have developed dedicated molecular mechanisms to tightly control expression levels of their genes where the specific transcriptomic signature across all genes eventually determines ...the cell’s phenotype. Modulating cellular phenotypes is of major interest to study their role in disease or to reprogram cells for the manufacturing of recombinant products, such as biopharmaceuticals. Cells of mammalian origin, for example Chinese hamster ovary (CHO) and Human embryonic kidney 293 (HEK293) cells, are most commonly employed to produce therapeutic proteins. Early genetic engineering approaches to alter their phenotype have often been attempted by “uncontrolled” overexpression or knock-down/-out of specific genetic factors. Many studies in the past years, however, highlight that rationally regulating and fine-tuning the strength of overexpression or knock-down to an optimum level, can adjust phenotypic traits with much more precision than such “uncontrolled” approaches. To this end, synthetic biology tools have been generated that enable (fine-)tunable and/or inducible control of gene expression. In this review, we discuss various molecular tools used in mammalian cell lines and group them by their mode of action: transcriptional, post-transcriptional, translational and post-translational regulation. We discuss the advantages and disadvantages of using these tools for each cell regulatory layer and with respect to cell line engineering approaches. This review highlights the plethora of synthetic toolboxes that could be employed, alone or in combination, to optimize cellular systems and eventually gain enhanced control over the cellular phenotype to equip mammalian cell factories with the tools required for efficient production of emerging, more difficult-to-express biologics formats.
●Overview of state-of-the art synthetic biology toolbox used for mammalian cell engineering.●Mode of action at the (post-) transcriptional and (post-)translational.●Emphasis on applications to engineer recombinant protein production.●Discussion of advantages and disadvantages of using these tools for each cell regulatory layer.
Reality‐enhancing technologies such as augmented reality and virtual reality are rapidly becoming a part of everyday life. Seizing this moment, we set out a research agenda for studying the ...psychological mechanisms underpinning consumer experiences with these new technologies, structured around four application areas: (1) delivering innovative offerings, (2) supporting sustainability and consumer well‐being interventions, (3) balancing value cocreation and privacy concerns, and (4) achieving new modes and means of impact. For each area, we identify research directions that can guide the development and use of reality‐enhancing technologies for the realization of next‐generation consumer experiences. We explicitly balance potential advantages and disadvantages, thus encouraging researchers and practitioners to prioritize developing the “purpose” of these technologies, by focusing on the psychological mechanisms that underlie their use, over the technological development of their “pixels.” In this way, we guide the impactful development of reality‐enhancing technologies for applications with significance for consumers and firms.
Trolling is a form of consumer misbehavior that involves deliberate, deceptive, and mischievous attempts to provoke reactions from other online users. This research draws on actor-network theory to ...explore the assemblages of human and non-human entities that allow and perpetuate online trolling behaviors. By taking a practice-focused multi-sited ethnographic research approach, the research shows that online trolling is often an unintended consequence of interactions between human and non-human entities that are joined in the performance of trolling behavior. These entities include: troll(s), target(s), a medium of exchange, audience(s), other trolls, trolling artifacts, regulators, revenue streams, and assistants. Some of these actors (i.e., troll, target, medium) are playing a role in initiating, and other actors are (un)intentionally sustaining trolling by celebrating it, boosting it, facilitating it, and normalizing it. The findings highlight the role of nontraditional actors in the performance of misbehaviors and suggest that effective management of online consumer misbehaviors such as trolling will include managing the socio-technical networks that allow and fuel these misbehaviors.
Purpose
This paper aims to examine the types of user misbehaviours in the sharing economy (SE) context. SE offers a fruitful study setting due to the scope of potential misbehaviour and the expanded ...role of consumers.
Design/methodology/approach
The study drew on online archival data from the AirbnbHell.com website, where people share their stories about their Airbnb-related negative experiences. The authors reviewed 405 hosts’, guests’ and neighbours’ stories and coded the identified forms of misbehaviours into categories. The typology thus developed was validated in the context of the Uber Rides service.
Findings
User misbehaviours in the SE context can be distinguished based on the domain in which the user role is violated and the nature of violated norms. These two conceptual distinctions delineate a four-fold typology of user misbehaviours: illegal, unprofessional, unbefitting and uncivil behaviours.
Research limitations/implications
The trustworthiness of the stories could not be assessed.
Practical implications
The presented typology can be used as a mapping tool that facilitates detection of the full scope of misbehaviours and as a managerial tool that provides ideas for effective management of misbehaviours that correspond to each category.
Originality/value
The paper presents the first empirically derived comprehensive typology of user misbehaviours in SE settings. This typology enables classification of a broad set of misbehaviours, including previously overlooked unprofessional behaviours carried out by peer-service providers. The study also puts forward a revised definition of consumer misbehaviours that encompasses the impact of misbehaviours on parties not directly involved in the SE-mediated exchange.
Mammalian cells frequently encounter subtle perturbations during recombinant protein production. Identifying the genetic factors that govern the cellular stress response can facilitate targeted ...genetic engineering to obtain production cell lines that demonstrate a higher stress tolerance. To simulate nutrient stress, Chinese hamster ovary (CHO) cells were transferred into a glutamine(Q)‐free medium and transcriptional dynamics using thiol(SH)‐linked alkylation for the metabolic sequencing of RNA (SLAM‐seq) along with standard RNA‐seq of stressed and unstressed cells were investigated. The SLAM‐seq method allows differentiation between actively transcribed, nascent mRNA, and total (previously present) mRNA in the sample, adding an additional, time‐resolved layer to classic RNA‐sequencing. The cells tackle amino acid (AA) limitation by inducing the integrated stress response (ISR) signaling pathway, reflected in Atf4 overexpression in the early hours post Q deprivation, leading to subsequent activation of its targets, Asns, Atf3, Ddit3, Eif4ebp1, Gpt2, Herpud1, Slc7a1, Slc7a11, Slc38a2, Trib3, and Vegfa. The GCN2‐eIF2α‐ATF4 pathway is confirmed by a significant halt in transcription of translation‐related genes at 24 h post Q deprivation. The downregulation of lipid synthesis indicates the inhibition of the mTOR pathway, further confirmed by overexpression of Sesn2. Furthermore, SLAM‐seq detects short‐lived transcription factors, such as Egr1, that would have been missed in standard experimental designs with RNA‐seq. Our results describe the successful establishment of SLAM‐seq in CHO cells and therefore facilitate its future use in other scenarios where dynamic transcriptome profiling in CHO cells is essential.
A method to analyze transcriptional dynamics, thiol(SH)‐linked alkylation for the metabolic sequencing of RNA (SLAM‐seq), was first applied to Chinese hamster ovary (CHO) cells to study immediate response to stress on the example of nutrient limitation by transfer to glutamine‐free medium. SLAM‐seq allows the differentiation between nascent and previously present mRNA in the sample, revealing modulation of various metabolic pathways, and detects short‐lived transcription factors frequently missed in standard experimental designs with RNA‐seq.
Modulation of expression levels of endogenous or recombinant genes can be of great interest for diverse applications, such as the study of genotype-phenotype relationships for a gene of interest, or ...fine-tuning of transcription to determine physiologically relevant effects of gene expression levels. During the last decades, several synthetic biology tools were established to control gene expression in mammalian cells such as Chinese hamster ovary (CHO) cells, one of the most important cell systems for basic research as well as the production of biopharmaceuticals. Here we describe the use of triplex forming oligos (TFOs), short RNA or ssDNA molecules that can bind to the major grove of their target duplex with great specificity, to control transgene expression in CHO cells. For proof of concept, a panel of TFOs with a size of 10–20 nts were designed with the help of the on-line tool Triplexator targeting the viral cytomegalovirus (CMV) promoter/enhancer region controlling the downstream reporter gene hCD4. The effect of TFOs was tested as ssDNA oligos pre-annealed to the promoter/enhancer region in vitro as well as upon endogenous transcription of the TFO as an RNA molecule binding to their target duplex in vivo. Results showed that not only binding of the TFO, but the exact location of triplex formation within the promoter/enhancer is paramount for transcription inhibition. After relieving a binding conflict by introducing a point mutation within the CMV promoter, longer TFOs (26–30 nts) could be designed and analysed. Selected TFOs achieved a reduction in recombinant hCD4 expression of up to 85% in CHO-K1 cells.
•Triplex forming oligo sequences (TFOs) with a size of 10–20 nts were designed to target the viral cytomegalovirus (CMV) promoter/enhancer .•Binding of the TFO, but also the exact location of triplex formation within the promoter/enhancer is paramount for transcription inhibition.•Selected TFOs achieved a reduction in recombinant gene expression of up to 85% in CHO-K1 cells.
This paper explores the cultural dynamics underpinning platformization by unpacking the emergence of the sharing economy—a vital terrain of platformization—as a culturally significant category. ...Drawing on online archival data, our study reveals the important role of social movement organizations (SMOs) in establishing the sharing economy as a prominent cultural category and infusing it with powerful social meanings. We outline the discursive strategies used by SMOs to articulate this macro-market category, and to frame platform technology as a benevolent enabler of social change. Our study contributes to platformization research by turning attention to how cultural dynamics (i.e., the discursive strategies giving rise to the emergence of sharing economy) shape platformization. In addition, we contribute to market system dynamic research by expanding the focus of investigation from singular industries to the macro economy level, shedding light on new discursive dynamics (e.g., discursive strategies for articulating and technologizing the emergent economy), and by the extending previous work on the role of SMOs and social movements in market shaping.
Building upon the rich tradition of research on governmentality, this paper introduces the notion of market-based governance (i.e. the coordinated efforts of companies to align the conduct of its ...constituents with the institutional norms, values and interests of the company), and presents an empirical investigation of market-based governance in the context of a sharing economy platform, Airbnb. Whereas existing governmentality research has focused on specific discourses or aspects of governance in the marketplace, our aim is to develop broader-spectrum conceptual tools for ‘ordering’ the increasingly multifaceted forms of marked-based governance. We show that Airbnb mobilizes three distinct logics of governance (i.e. the regulatory, competitive and communitarian) which subsume diverse modes of power (i.e. the sovereign, disciplinary and pastoral) that contribute to the cultivation of governable subjects (i.e. the compliant subject, entrepreneurial subject and community member). The theoretical framework developed in this work is applied to critically reflect on emergent forms of market-based governance, the dilemmas of multi-logic governance and the uneven geographies of market-based governance.
Trolling involves deliberate, deceptive and mischievous attempts to provoke reactions from other online users. Even though trolling causes problems for marketers and consumers, there has been little ...discussion about what trolling actually is and how marketers should respond to it. The present conceptual study addresses these gaps. First, we present a working, integrative definition of trolling behaviours, arguing that trolling is substantively different from cyberbullying. Next, we present the challenges of current trolling regulations, showing that trolling is sometimes the result of the regulations themselves. The paper concludes with a presentation of the conceptual model of the manifestation of trolling behaviours. The model informs and assists scholars and marketing practitioners concerned with understanding and addressing trolling.
The metaverse has been heralded as a next frontier for fueling strategic business opportunities. At the same time, recent months have witnessed explosive volatility in the market potential of ...proposed metaverse offerings. As a result, businesses are struggling to set a meaningful strategic course through an uncharted and rapidly changing landscape. We argue that the success of developing and scaling the metaverse as a vibrant new business ecosystem is largely dependent on the understanding that it is a unified and immersive reality where the physical and synthetic customer experiences seamlessly converge. For this to work, businesses and their customers need to be able to suspend their disbelief that synthetic elements are inherently false. We therefore consider the metaverse as a differentiated experience by exploring the promise and perils of falsity. We discuss how businesses can strategically embrace falsity by harnessing its intended—as well as mitigating its unintended—consequences, as they maneuver through major technological challenges in capturing customer value. We offer a diverse set of examples that illustrate how these strategies translate into managerial actions to competitively succeed in this new reality.
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