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Background: Cancer represents a major cause of mortality globally and by 2050 will be the major cause of ill health and death across the world, most particularly in low- and middle-income countries (LMIC). For forty years, there has been increasing recognition of the need to better understand how the modifiable factors related to diet, nutrition and physical activity can influence the risk of cancer, responses to treatment, and survival. Scope and approach: The International Collaboration on Nutrition in relation to Cancer (ICONIC) - a task force of the International Union of Nutritional Sciences (IUNS) - was established in 2018, as a development from the UK NIHR Cancer and Nutrition Collaboration and as a mechanism to bring together wider international expressions of interest in nutrition and cancer. Key findings: ICONIC has engaged in a range of activities, with a current focus of effort in three main areas: 1) building wider capability and stronger capacity for excellence in research and practice in Africa, with the longer-term ambition to develop a high quality, context-specific research programme in this region, 2) facilitating international collaboration and developing activities in the area of childhood cancers, and 3) developing an agenda for prehabilitation (personalised management of exercise, nutrition and psychological support before the start of definitive treatment) for cancer. Conclusions: ICONIC's ambition is to build an international nutrition and cancer community - spanning research, education and training, in clinical and public health practice – to create coherence and common language across the two communities, and promote improved care and outcomes for those affected by cancer.

Summary Artificial cells can shed new light on the molecular basis for life and hold potential for new chemical technologies. Inspired by how nature dynamically regulates its membrane compartments, we aim to repurpose the endosomal sorting complex required for transport (ESCRT) to generate complex membrane architectures as suitable scaffolds for artificial cells. Purified ESCRT-III components perform topological transformations on giant unilamellar vesicles to create complex “vesicles-within-a-vesicle” architectures resembling the compartmentalization in eukaryotic cells. Thus far, the proposed mechanisms for this activity are based on how assembly and disassembly of ESCRT-III on the membrane drives deformation. Here we demonstrate the existence of a negative feedback mechanism from membrane mechanics that regulates ESCRT-III remodeling activity. Intraluminal vesicle (ILV) formation removes excess membrane area, increasing tension, which in turn suppresses downstream ILV formation. This mechanism for in vitro regulation of ESCRT-III activity may also have important implications for its in vivo functions., Graphical Abstract, Highlights • ESCRT proteins are used to create compartmentalized artificial cell architectures • In vitro ESCRT activity is weakly dependent on the stoichiometry of Vps20 or Vps24 • ESCRT function is strongly regulated by membrane tension • Membrane tension provides a negative feedback mechanism to attenuate remodeling, Biochemistry; Bioengineering; Cell Biology; Biophysics

On 11th March 2020, the UK government announced plans for the scaling of COVID-19 testing, and on 27th March 2020 it was announced that a new alliance of private sector and academic collaborative laboratories were being created to generate the testing capacity required. The Cambridge COVID-19 Testing Centre (CCTC) was established during April 2020 through collaboration between AstraZeneca, GlaxoSmithKline, and the University of Cambridge, with Charles River Laboratories joining the collaboration at the end of July 2020. The CCTC lab operation focussed on the optimised use of automation, introduction of novel technologies and process modelling to enable a testing capacity of 22,000 tests per day. Here we describe the optimisation of the laboratory process through the continued exploitation of internal performance metrics, while introducing new technologies including the Heat Inactivation of clinical samples upon receipt into the laboratory and a Direct to PCR protocol that removed the requirement for the RNA extraction step. We anticipate that these methods will have value in driving continued efficiency and effectiveness within all large scale viral diagnostic testing laboratories.

Mechanisms that control nuclear membrane remodeling are essential to maintain the integrity of the nucleus but remain to be fully defined. Here, we identify a phosphatidic acid (PA)–binding capacity in the nuclear envelope (NE)–specific ESCRT, Chm7, in budding yeast. Chm7’s interaction with PA-rich membranes is mediated through a conserved hydrophobic stretch of amino acids, which confers recruitment to the NE in a manner that is independent of but required for Chm7’s interaction with the LAP2-emerin-MAN1 (LEM) domain protein Heh1 (LEM2). Consistent with the functional importance of PA binding, mutation of this region abrogates recruitment of Chm7 to membranes and abolishes Chm7 function in the context of NE herniations that form during defective nuclear pore complex (NPC) biogenesis. In fact, we show that a PA sensor specifically accumulates within these NE herniations. We suggest that local control of PA metabolism is important for ensuring productive NE remodeling and that its dysregulation may contribute to pathologies associated with defective NPC assembly.

Syftet med uppdraget är att sammanställa befintlig kunskap över hur besökstrycket i naturen ser ut under 2020–2021 jämfört med tidigare och vilka utmaningar detta har lett till, med anledning av medieuppgifter kring ökat tryck och negativa effekter som en följd av corona-pandemin. Resultatet ska kunna användas i planering av framtida insatser. Målet är att sammanställa befintlig kunskap och genom analys skapa en mer sammanhållen bild över situationen och visa på behov av ytterligare kunskap. Fem olika utmaningar valdes ut av Naturvårdsverket. Analys och konsekvenser av ökat friluftsliv

Thaller et al. demonstrate that direct binding between phosphatidic acid (PA) and the ESCRT Chm7 is required for nuclear envelope surveillance; PA also accumulates at nuclear envelope herniations. Thus, tight control of PA metabolism is required for nuclear envelope homeostasis., Mechanisms that control nuclear membrane remodeling are essential to maintain the integrity of the nucleus but remain to be fully defined. Here, we identify a phosphatidic acid (PA)–binding capacity in the nuclear envelope (NE)–specific ESCRT, Chm7, in budding yeast. Chm7’s interaction with PA-rich membranes is mediated through a conserved hydrophobic stretch of amino acids, which confers recruitment to the NE in a manner that is independent of but required for Chm7’s interaction with the LAP2-emerin-MAN1 (LEM) domain protein Heh1 (LEM2). Consistent with the functional importance of PA binding, mutation of this region abrogates recruitment of Chm7 to membranes and abolishes Chm7 function in the context of NE herniations that form during defective nuclear pore complex (NPC) biogenesis. In fact, we show that a PA sensor specifically accumulates within these NE herniations. We suggest that local control of PA metabolism is important for ensuring productive NE remodeling and that its dysregulation may contribute to pathologies associated with defective NPC assembly.

Mechanisms that control nuclear membrane remodeling are essential to maintain the integrity of the nucleus but remain to be fully defined. Here, we identify a phosphatidic acid (PA)-binding activity in the nuclear envelope-specific ESCRT, Chm7, in budding yeast. PA-binding is mediated through a conserved hydrophobic stretch of amino acids, which confers specific binding to the inner nuclear membrane (INM). This INM-binding is independent but nonetheless required for interaction with the LAP2-emerin-MAN1 (LEM) domain protein, Heh1 (LEM2). Consistent with the functional importance of PA-binding, mutation of this region inhibits recruitment of Chm7 to the INM and abolishes Chm7 function in the context of nuclear envelope herniations or “blebs” that form during defective nuclear pore complex (NPC) biogenesis. In fact, we show that PA accumulates at nuclear envelope herniations. We suggest that local control of PA metabolism is important for ensuring productive nuclear envelope remodeling and that its dysregulation may contribute to pathologies associated with defective NPC assembly.

The endosomal sorting complex required for transport (ESCRT) organises in supramolecular structures on the surface of lipid bilayers to drive membrane invagination and scission of intraluminal vesicles (ILVs), a process also controlled by membrane mechanics. However, ESCRT association with the membrane is also mediated by electrostatic interactions with anionic phospholipids. Phospholipid distribution within natural biomembranes is inhomogeneous due to, for example, the formation of lipid rafts and curvature-driven lipid sorting. Here, we have used phase-separated giant unilamellar vesicles (GUVs) to investigate the link between phosphatidylserine (PS)-rich lipid domains and ESCRT activity. We employ GUVs composed of phase separating lipid mixtures, where unsaturated DOPS and saturated DPPS lipids are incorporated individually or simultaneously to enhance PS localisation in liquid disordered (Ld) and/or liquid ordered (Lo) domains, respectively. PS partitioning between the coexisting phases is confirmed by a fluorescent Annexin V probe. Ultimately, we find that ILV generation promoted by ESCRTs is significantly enhanced when PS lipids localise within Ld domains. However, the ILVs that form are rich in Lo lipids. We interpret this surprising observation as preferential recruitment of the Lo phase beneath the ESCRT complex due to its increased rigidity, where the Ld phase is favoured in the neck of the resultant buds to facilitate the high membrane curvature in these regions of the membrane during the ILV formation process. Ld domains offer lower resistance to membrane bending, demonstrating a mechanism by which the composition and mechanics of membranes can be coupled to regulate the location and efficiency of ESCRT activity.

Poetry is fundamentally an engaged level of life in the world of readers and poets alike. It surrounds those concerned, often with an understanding that extends beyond its possibility as the comprehension of meaningful content embodied in a written or spoken artifact. For readers of poetry, memorized lines and rhythms emerge seemingly out of nowhere to be recited, and poets often tell us that lines, rhythms and linguistic content often appear without prompting as they are carried away in writing poetry. Yet literary studies and phenomenology have tended to focus either on the poetic artifact and its cognition, or poetry as a special sphere and mode of revelation. This paper seeks to question the experience of the poetic as a special level of life and an embodied activity, and sketches some points of entry in which we can enter into a discussion on the poetic as such.

Chronic obstructive pulmonary disease (COPD), which is most commonly caused by cigarette smoke (CS) exposure, is the third leading cause of death worldwide. The cystic fibrosis transmembrane conductance regulator (CFTR) is an apical membrane anion channel that is widely expressed in epithelia throughout the body. In the airways, CFTR plays an important role in fluid homeostasis and helps flush mucus and inhaled pathogens/toxicants out of the lung. Inhibition of CFTR leads to mucus stasis and severe airway disease. CS exposure also inhibits CFTR, leading to the decreased anion secretion/hydration seen in COPD patients. However, the underlying mechanism is poorly understood. Here, we report that CS causes CFTR to be internalized in a clathrin/dynamin-dependent fashion. This internalization is followed by retrograde trafficking of CFTR to the endoplasmic reticulum. Although this internalization pathway has been described for bacterial toxins and cargo machinery, it has never been reported for mammalian ion channels. Furthermore, the rapid internalization of CFTR is dependent on CFTR dephosphorylation by calcineurin, a protein phosphatase that is upregulated by CS. These results provide new insights into the mechanism of CFTR internalization, and may help in the development of new therapies for CFTR correction and lung rehydration in patients with debilitating airway diseases such as COPD.

Anthropometric measures relating to body size, weight and composition are increasingly being associated with cancer risk and progression. Whilst practical in epidemiologic research, where population-level associations with disease are revealed, it is important to be aware that such measures are imperfect markers of the internal physiological processes that are the actual correlates of cancer development. Body mass index (BMI), the most commonly used marker for adiposity, may mask differences between lean and adipose tissue, or fat distribution, which varies across individuals, ethnicities, and stage in the lifespan. Other measures, such as weight gain in adulthood, waist circumference and waist-to-hip ratio, contribute information on adipose tissue distribution and insulin sensitivity. Single anthropometric measures do not capture maturational events, including the presence of critical windows of susceptibility (i.e., age of menarche and menopause), which presents a challenge in epidemiologic work. Integration of experimental research on underlying dynamic genetic, hormonal, and other non-nutritional mechanisms is necessary for a confident conclusion of the overall evidence in cancer development and progression. This article discusses the challenges confronted in evaluating and interpreting the current evidence linking anthropometric factors and cancer risk as a basis for issuing recommendations for cancer prevention.

The dynamins represent a superfamily of proteins that have been shown to function in a wide range of membrane fusion and fission events. An increasing number of mutations in the human classical dynamins, Dyn-1 and Dyn-2 has been reported, with diseases caused by these changes ranging from Charcot-Marie-Tooth disorder to epileptic encephalopathies. The budding yeast, Saccharomyces cerevisiae expresses a single dynamin-related protein that functions in membrane trafficking, and is considered to play a similar role to Dyn-1 and Dyn-2 during scission of endocytic vesicles at the plasma membrane. Large parts of the dynamin protein are highly conserved across species and this has enabled us in this study to select a number of disease causing mutations and to generate equivalent mutations in Vps1. We have then studied these mutants using both cellular and biochemical assays to ascertain functions of the protein that have been affected by the changes. Specifically, we demonstrate that the Vps1-G397R mutation (Dyn-2 G358R) disrupts protein oligomerization, Vps1-A447T (Dyn-1 A408T) affects the scission stage of endocytosis, while Vps1-R298L (Dyn-1 R256L) affects lipid binding specificity and possibly an early stage in endocytosis. Overall, we consider that the yeast model will potentially provide an avenue for rapid analysis of new dynamin mutations in order to understand the underlying mechanisms that they disrupt.

The yeast dynamin-like protein Vps1 has roles at multiple stages of membrane trafficking including Golgi to vacuole transport, endosomal recycling, endocytosis and in peroxisomal fission. While the majority of the Vps1 amino acid sequence shows a high level of identity with the classical mammalian dynamins, it does not contain a pleckstrin homology domain (PH domain). The Dyn1 PH domain has been shown to bind to lipids with a preference for PI(4,5)P2 and it is considered central to the function of Dyn1 in endocytosis. The lack of a PH domain in Vps1 has raised questions as to whether the protein can function directly in membrane fusion or fission events. Here we demonstrate that the region Insert B, located in a position equivalent to the dynamin PH domain, is able to bind directly to lipids and that mutation of three lysine residues reduces its capacity to interact with lipids, and in particular with PI(4,5)P2. The Vps1 KKK-AAA mutant shows more diffuse staining but does still show some localization to compartments adjacent to vacuoles and to endocytic sites suggesting that other factors are also involved in its recruitment. This mutant selectively blocks endocytosis, but is functional in other processes tested. While mutant Vps1 can localise to endocytic sites, the mutation results in a significant increase in the lifetime of the endocytic reporter Sla2 and a high proportion of defective scission events. Together our data indicate that the lipid binding capacity of the Insert B region of Vps1 contributes to the ability of the protein to associate with membranes and that its capacity to interact with PI(4,5)P2 is important in facilitating endocytic scission.

Artificial cells can shed new light on the molecular basis for life and hold potential for new chemical technologies. Inspired by how nature dynamically regulates its membrane compartments, we aim to repurpose the endosomal sorting complex required for transport (ESCRT) to generate complex membrane architectures as suitable scaffolds for artificial cells. Purified ESCRT-III components perform topological transformations on giant unilamellar vesicles (GUVs) to create complex “vesicles-within-a-vesicle” architectures resembling the compartmentalisation in eukaryotic cells. Thus far, the proposed mechanisms for this activity are based on how assembly and disassembly of ESCRT-III on the membrane drives deformation. Here we demonstrate the existence of a negative feedback mechanism from membrane mechanics that regulates ESCRT-III activity. ILV formation removes excess membrane area, increasing tension, which in turn suppresses downstream ILV formation. This mechanism for in vitro regulation of ESCRT-III activity may also have important implications for its in vivo functions.

The complexity of eukaryotic cells is underscored by the compartmentalization of chemical signals by phospholipid membranes. A grand challenge of synthetic biology is building life from the ‘bottom-up’, for the purpose of generating systems simple enough to precisely interrogate biological pathways or for adapting biology to perform entirely novel functions. Achieving compartmentalization of chemistries in an addressable manner is a task exquisitely refined by nature and embodied in a unique membrane remodelling machinery that pushes membranes away from the cytosol, the ESCRT-III (endosomal sorting complex required for transport-III) complex. Here, we show efforts to engineer a single ESCRT-III protein merging functional features from its different components. The activity of such a designed ESCRT-III is shown by its ability to drive the formation of compartments encapsulating fluorescent cargo. It appears that the modular nature of ESCRT-III allows its functional repurposing into a minimal machinery that performs sophisticated membrane remodelling, therefore enabling its use to create eukaryotic-like multi-compartment architectures.

Early oesophageal adenocarcinoma (OA) and pre-neoplastic dysplasia may be treated with endoscopic resection and ablative techniques such as photodynamic therapy (PDT). Though effective, discrete areas of disease may be missed leading to recurrence. PDT further suffers from the side effects of off-target photosensitivity. A tumour specific and light targeted therapeutic agent with optimised pharmacokinetics could be used to destroy residual cancerous cells left behind after resection. A small molecule antibody-photosensitizer conjugate was developed targeting human epidermal growth factor receptor 2 (HER2). This was tested in an in vivo mouse model of human OA using a xenograft flank model with clinically relevant low level HER2 expression and heterogeneity. In vitro we demonstrate selective binding of the conjugate to tumour versus normal tissue. Light dependent cytotoxicity of the phototherapy agent in vitro was observed. In an in vivo OA mouse xenograft model the phototherapy agent had desirable pharmacokinetic properties for tumour uptake and blood clearance time. PDT treatment caused tumour growth arrest in all the tumours despite the tumours having a clinically defined low/negative HER2 expression level. This new phototherapy agent shows therapeutic potential for treatment of both HER2 positive and borderline/negative OA.

The complexity of eukaryotic cells is underscored by the compartmentalization of chemical signals by phospholipid membranes. A grand challenge of synthetic biology is building life from the ‘bottom-up’, for the purpose of generating systems simple enough to precisely interrogate biological pathways or for adapting biology to perform entirely novel functions. Achieving compartmentalization of chemistries in an addressable manner is a task exquisitely refined by nature and embodied in a unique membrane remodelling machinery that pushes membranes away from the cytosol, the ESCRT-III (endosomal sorting complex required for transport-III) complex. Here, we show efforts to engineer a single ESCRT-III protein merging functional features from its different components. The activity of such a designed ESCRT-III is shown by its ability to drive the formation of compartments encapsulating fluorescent cargo. It appears that the modular nature of ESCRT-III allows its functional repurposing into a minimal machinery that performs sophisticated membrane remodelling, therefore enabling its use to create eukaryotic-like multi-compartment architectures.