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Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease, with a clear genetic component. While most SLE patients carry rare gene variants in lupus risk genes, little is known about their contribution to disease pathogenesis. Amongst them,SH2B3- a negative regulator of cytokine and growth factor receptor signaling – harbors rare coding variants in over 5% of SLE patients. Here we show that unlike the variant found exclusively in healthy controls, mostSH2B3rare variants found in lupus patients are predominantly hypomorphic alleles. Generation of two mouse lines carrying variants orthologous to those found in patients revealed SH2B3 is important to limit the numbers of immature and transitional B cells. Furthermore, hypomorphic SH2B3 was shown to impair negative selection of immature/transitional self-reactive B cells and accelerate autoimmunity in sensitized mice, at least in part due to increased IL-4R signaling and BAFF-R expression. This work identifies a previously unappreciated role forSH2B3in human B cell tolerance and lupus risk.SummaryZhanget al. reveal a role for hypomorphic SH2B3 in lupus risk. The study shows rare and damaging variants identified in lupus patients enable breach of B cell immune tolerance checkpoints and suggests involvement for dysregulated IL-4R signaling and BAFF-R expression.

LNK is a member of the SH2B family of adaptor proteins and is a non-redundant regulator of cytokine signalling. Cytokines are secreted intercellular messengers that bind to specific receptors on the surface of target cells to activate the Janus Kinase-Signal Transducer and Activator of Transcription (JAK-STAT) signalling pathway. Activation of the JAK-STAT pathway leads to proliferative and often inflammatory effects, and so the amplitude and duration of signalling are tightly controlled. LNK binds phosphotyrosine residues to signalling proteins downstream of cytokines and constrains JAK-STAT signalling. Mutations in LNK have been identified in a range of haematological and inflammatory diseases due to increased signalling following the loss of LNK function. Here, we review the regulation of JAK-STAT signalling via the adaptor protein LNK and discuss the role of LNK in haematological diseases.

Randomized trials in acute myeloid leukemia (AML) have demonstrated improved survival by the BCL-2 inhibitor venetoclax combined with azacitidine in older patients, and clinical trials are actively exploring the role of venetoclax in combination with intensive chemotherapy in fitter patients with AML. As most patients still develop recurrent disease, improved understanding of relapse mechanisms is needed. We find that 17% of patients relapsing after venetoclax-based therapy for AML have acquired inactivating missense or frameshift/nonsense mutations in the apoptosis effector gene BAX. In contrast, such variants were rare after genotoxic chemotherapy. BAX variants arose within either leukemic or preleukemic compartments, with multiple mutations observed in some patients. In vitro, AML cells with mutated BAX were competitively selected during prolonged exposure to BCL-2 antagonists. In model systems, AML cells rendered deficient for BAX, but not its close relative BAK, displayed resistance to BCL-2 targeting, whereas sensitivity to conventional chemotherapy was variable. Acquired mutations in BAX during venetoclax-based therapy represent a novel mechanism of resistance to BH3-mimetics and a potential barrier to the long-term efficacy of drugs targeting BCL-2 in AML.

Almost all interactions and reactions that occur in living organisms involve proteins. The various biological roles of proteins include, but are not limited to, signal transduction, gene transcription, cell death, immune function, structural support, and catalysis of all the chemical reactions that enable organisms to survive. The varied roles of proteins have led to them being dubbed ‘the workhorses of all living organisms’. This article discusses the functions of proteins and how protein function is studied in a laboratory setting. In this article, we begin by examining the functions of protein domains, followed by a discussion of some of the major classes of proteins based on their function. We consider protein binding in detail, which is central to protein function. We then examine how protein function can be altered through various mechanisms including post-translational modification, and changes to environment, oligomerisation and mutations. Finally, we consider a handful of the techniques employed in the laboratory to understand and measure the function of proteins.

Microbial dysbiosis has emerged as a modulator of oncogenesis and response to therapy, particularly in lung cancer. Here, we investigate the evolution of the gut and lung microbiomes following exposure to a tobacco carcinogen. We performed 16S rRNA-Seq of fecal and lung samples collected prior to and at several timepoints following (nicotine-specific nitrosamine ketone/NNK) exposure in Gprc5a−/− mice that were previously shown to exhibit accelerated lung adenocarcinoma (LUAD) development following NNK exposure. We found significant progressive changes in human-relevant gut and lung microbiome members (e.g., Odoribacter, Alistipes, Akkermansia, and Ruminococus) that are closely associated with the phenotypic development of LUAD and immunotherapeutic response in human lung cancer patients. These changes were associated with decreased short-chain fatty acids (propionic acid and butyric acid) following exposure to NNK. We next sought to study the impact of Lcn2 expression, a bacterial growth inhibitor, given our previous findings on its protective role in LUAD development. Indeed, we found that the loss of Lcn2 was associated with widespread gut and lung microbiome changes at all timepoints, distinct from those observed in our Gprc5a−/− mouse model, including a decrease in abundance and diversity. Our overall findings apprise novel cues implicating microbial phenotypes in the development of tobacco-associated LUAD.

The SH2B family of adaptor proteins, SH2-B, APS, and LNK are key modulators of cellular signalling pathways. Whilst SH2-B and APS have been partially structurally and biochemically characterised, to date there has been no such characterisation of LNK. Here we present two crystal structures of the LNK substrate recognition domain, the SH2 domain, bound to phosphorylated motifs from JAK2 and EPOR, and biochemically define the basis for target recognition. The LNK SH2 domain adopts a canonical SH2 domain fold with an additional N-terminal helix. Targeted analysis of binding to phosphosites in signalling pathways indicated that specificity is conferred by amino acids one- and three-residues downstream of the phosphotyrosine. Several mutations in LNK showed impaired target binding in vitro and a reduced ability to inhibit signalling, allowing an understanding of the molecular basis of LNK dysfunction in variants identified in patients with myeloproliferative disease., LNK is a potent negative regulator of cytokine signaling implicated in blood cells proliferation. Here the authors present structures of the substrate recognition (SH2) domain of LNK in complex with phosphorylated motifs from JAK2 and EPOR; providing insight into its binding specificity and mode of action.

Progressive multifocal leukoencephalopathy is a rare condition caused by the polyomavirus JC (JCV) affecting almost exclusively immunosuppressed individuals. Treatment strategies are limited and generally focus on immune reconstitution. Inhibition of Programmed cell death protein 1 (PD-1) has been associated with reduced CSF JC viral load and clinical stabilisation or improvement in 5 of 8 patients reported in a previous case series (Cortese et al., 2019)[i]. Here, we report three cases of PML in patients without HIV or immunosuppressive treatment who were treated with the checkpoint inhibitor pembrolizumab in an attempt to increase CD4+ and CD8+ T-cell activity against JCV. At time of submission, disease progression had halted in 2 of 3 patients (median follow-up=10months, 1-22months). We will detail presentation and disease course and discuss challenges experienced in the management of these patients.[i] Cortese I, Muranski P, Enose-Akahata Y, Ha SK, Smith B, Monaco M, Ryschkewitsch C, Major EO, Ohayon J, Schindler MK, Beck E, Reoma LB, Jacobson S, Reich DS, Nath A. Pembrolizumab Treatment for Pro- gressive Multifocal Leukoencephalopathy. N Engl J Med. 2019 Apr 25;380(17):1597-1605. doi: 10.1056/NEJMoa1815039. Epub 2019 Apr 10. PMID: 30969503.

More than 50 cytokines signal via the JAK/STAT pathway to orchestrate hematopoiesis, induce inflammation and control the immune response. Cytokines are secreted glycoproteins that act as intercellular messengers, inducing proliferation, differentiation, growth, or apoptosis of their target cells. They act by binding to specific receptors on the surface of target cells and switching on a phosphotyrosine-based intracellular signaling cascade initiated by kinases then propagated and effected by SH2 domain-containing transcription factors. As cytokine signaling is proliferative and often inflammatory, it is tightly regulated in terms of both amplitude and duration. Here we review molecular details of the cytokine-induced signaling cascade and describe the architectures of the proteins involved, including the receptors, kinases, and transcription factors that initiate and propagate signaling and the regulatory proteins that control it.

Interleukin 6 is the classical member of the IL-6 family of cytokines which triggers activation of the JAK/STAT signaling cascade in cells. IL-6 is a pleiotropic cytokine that acts on many cell types and plays a critical role in immune responses, inflammation, and haematopoiesis. Our understanding of the molecular mechanisms governing IL-6 signaling has been aided by numerous studies of this signal transduction pathway, including those utilising the M1 cell line. Here we discuss the studies that we and others have undertaken using the M1 line to examine IL-6 inducible genes, particularly those targets that acts as negative regulators of signaling. Finally, we present a model for the current understanding of the IL-6 signaling pathway at a structural and mechanistic level.

Coaches are frequently cited as potentially precipitating or preventing athletes’ engagement in doping. However, little is known about coaches’ perspectives. Therefore, the purpose of this study was to examine coaches’ perceptions of their role and actions in athletes’ anti-doping behaviour. Twenty-three coaches (M = 17, F = 6) working with performance athletes in Scotland participated in semi-structured interviews where topics related to doping and anti-doping were discussed. Thematic analysis, guided by Schön’s role frame and reflective conversation concepts, was used to develop themes. Analysis led to the development of four internal role frame themes: clean sport value, approach to preparation and performance, responsibility to athletes and knowledge; and five boundary role frame themes: Scottish/British sporting culture, potential for benefit, prevalence of doping and testing, clarity of responsibilities and consequences, and beyond coaches’ control. The coaches’ role frame supported an anti-doping stance, but, it also presented a risk and was insufficient to ensure action. Analysis of coaches’ reflective conversations revealed the issues set by the coaches differed and influenced subsequent actions and evaluations.

Plants produce energy in a sustainable way, they are very effective in converting light energy into a useable form. Utilising certain parts of plants in technology could become an efficient way to enhance energy production and improve sustainability. Integrating plants with technology would offer a 'green' way of producing elements for electronic circuits and reduce heavy metal waste. In this paper, we demonstrate that conducting polymers can be incorporated into living system such as celery. Electrical impedance analysis was used to establish the conductivity of celery with a conducting polymer (PEDOT:PSS) into its vascular system. It was demonstrated that electronic celery exhibited conductivity values of up to 0.55 ±0.03 S/cm. This conductivity value was sufficient to demonstrate the potential of celery electronics where celery stalks are used as electrodes in simple circuits.

Janus kinases (JAKs) are found constitutively associated with cytokine receptors and are present in an inactive state prior to cytokine exposure. Activating mutations of JAKs are causative for a number of leukemias, lymphomas, and myeloproliferative diseases. In particular, the JAK2V617F mutant is found in most human cases of polycythemia vera, a disease characterized by over-production of erythrocytes. The V617F mutation is found in the pseudokinase domain of JAK2 and it leads to cytokine-independent activation of the kinase, as does the orthologous mutation in other JAK-family members. The mechanism whereby this mutation hyperactivates these kinases is not well understood, primarily due to the fact that the full-length JAK proteins are difficult to produce for structural and kinetic studies. Here we have overcome this limitation to perform a series of enzymatic analyses on full-length JAK1 and its constitutively active mutant form (JAK1V658F). Consistent with previous studies, we show that the presence of the pseudokinase domain leads to a dramatic decrease in enzymatic activity with no further decrease from the presence of the FERM or SH2 domains. However, we find that the mutant kinase, in vitro, is indistinguishable from the wild-type enzyme in every measurable parameter tested: KM (ATP), KM (substrate), kcat, receptor binding, thermal stability, activation rate, dephosphorylation rate, and inhibitor affinity. These results show that the V658F mutation does not enhance the intrinsic enzymatic activity of JAK. Rather this data is more consistent with a model in which there are cellular processes and interactions that prevent JAK from being activated in the absence of cytokine and it is these constraints that are affected by disease-causing mutations.

Missense mutations in the leucine rich repeat kinase 2 (LRRK2) gene are the leading genetic cause of autosomal dominant familial Parkinson’s disease. We previously reported that two mutations within the ROC domain, namely R1441C and A1442P, exhibit increased protein degradation leading to lowered steady state LRRK2 protein levels in HEK293 cells. More recently, the common WD40 domain LRRK2 haplotype, Met2397, which is a risk factor for Crohn’s disease, has been shown to lower steady state protein levels in HEK293 cells. In view of recent evidence implicating LRRK2 and inflamemation in PD, we investigated the effects of Met2397 on LRRK2 expression, and compared them to the Thr2397 variant and other LRRK2 mutants. In this study, we transfected HEK293 cells with plasmid constructs encoding the different LRRK2 variants, and analyzed the resulting protein levels by Western blot and flow cytometry. Here we found that both the Met2397 and Thr2397 haplotypes yield similar levels of LRRK2 protein expression and do not appear to impact cell viability in HEK293 cells, compared to other LRRK mutants. Thus, we have concluded that the Met2397 haplotype is unlikely to play a role in LRRK2 mediated or idiopathic PD.

Essex is one of the driest parts of England and there is a gap in the availability and demand for water. The Abberton scheme is being undertaken to work towards alleviating this problem. Part of the scheme involves increasing the storage capacity at Abberton reservoir, by raising the full supply level of the reservoir by 3·2 m. The reservoir is owned by Essex and Suffolk Water who are part of Northumbrian Water Limited. The project is large in scope and there are many interesting aspects including raising the main dam while maintaining an operational reservoir, modification of the existing drawdown facilities, construction of several col dams, modification to the existing B1026 causeway embankment and the upgrading of the offtake pumping station. This paper focuses on the modification of the bottom outlet located in the valve tower, on the upstream slope of the main dam. The paper describes the arrangement and condition of the existing bottom outlet and discusses its capacity, for both existing and future conditions. It reviews the drawdown capacity at the reservoir and compares it to standards commonly applied elsewhere in the UK. A description is given of some of the studies that were undertaken during design development to explore how the drawdown capability might be improved. Construction is currently underway and the paper concludes with a summary of progress to date.