Non-interchangeable functions of efflux transporters of Pseudomonas aeruginosa in survival under infection-associated stress.

Pseudomonas aeruginosa is a challenging opportunistic pathogen due to its intrinsic and acquired mechanisms of antibiotic resistance. A large repertoire of efflux transporters actively expels antibiotics, toxins, and metabolites from cells and enables growth of P. aeruginosa in diverse environments. In this study, we analyzed the roles of representative efflux pumps from the Resistance-Nodulation-Division (RND), Major Facilitator Superfamily (MFS), and Small Multidrug Resistance (SMR) families of proteins in the susceptibility of P. aeruginosa to antibiotics and bacterial growth under stresses imposed by human hosts during bacterial infections: an elevated temperature, osmotic stress, low iron, bile salts, and acidic pH. We selected five RND pumps MexAB-OprM, MexEF-OprN, MexCD-OprJ, MuxABC-OpmB, and TriABC-OpmH that differ in their substrate specificities and expression profiles, two MFS efflux pumps PA3136-3137 and PA5158-5160 renamed here into MfsAB and MfsCD-OpmG, respectively, and an SMR efflux transporter PA1540-1541 (MdtJI). We found that the most promiscuous RND pumps such as MexEF-OprN and MexAB-OprM are integrated into diverse survival mechanisms and enable P. aeruginosa growth under various stresses. MuxABC-OpmB and TriABC-OpmH pumps with narrower substrate spectra are beneficial only in the presence of the iron chelator 2,2'-dipyridyl and bile salts, respectively. MFS pumps do not contribute to antibiotic efflux but play orthogonal roles in acidic pH, low iron, and in the presence of bile salts. In contrast, MdtJI protects against polycationic antibiotics but does not contribute to survival under stress. Thus, efflux pumps play specific, non-interchangeable functions in P. aeruginosa cell physiology and bacterial survival under stresses. IMPORTANCE: The role of multidrug efflux pumps in the intrinsic and clinical levels of antibiotic resistance in Pseudomonas aeruginosa and other gram-negative bacteria is well-established. Their functions in bacterial physiology, however, remain unclear. The P. aeruginosa genome comprises an arsenal of efflux pumps from different protein families, the substrate specificities of which are typically assessed by measuring their impact on susceptibility to antibiotics. In this study, we analyzed how deletions and overproductions of efflux pumps affect P. aeruginosa growth under human-infection-induced stresses. Our results show that the physiological functions of multidrug efflux pumps are non-redundant and essential for the survival of this important human pathogen under stress.

AdeIJK Pump-Specific Inhibitors Effective against Multidrug Resistant Acinetobacter baumannii.

Multidrug-resistant Acinetobacter baumannii is a serious threat pathogen rapidly spreading in clinics and causing a range of complicated human infections. The major contributor to A. baumannii antibiotic resistance is the overproduction of AdeIJK and AdeABC multidrug efflux pumps of the resistance-nodulation-division (RND) superfamily of proteins. The dominant role of efflux in antibiotic resistance and the relatively high permeability of the A. baumannii outer membrane to amphiphilic compounds make this pathogen a promising target for the discovery of clinically relevant efflux pump inhibitors. In this study, we identified 4,6-diaminoquoniline analogs with inhibitory activities against A. baumannii AdeIJK efflux pump and followed up on these compounds with a focused synthetic program to improve the target specificity and to reduce cytotoxicity. We identified several candidates that potentiate antibacterial activities of antibiotics erythromycin, tetracycline, and novobiocin not only in the laboratory antibiotic susceptible strain A. baumannii ATCC17978 but also in multidrug-resistant clinical isolates AB5075 and AYE. The best analogs potentiated the activities of antibiotics in low micromolar concentrations, did not have antibacterial activities on their own, inhibited AdeIJK-mediated efflux of its fluorescent substrate ethidium ion, and had low cytotoxicity in A549 human lung epithelial cells.

Characteristics of Adolescents' and Young Adults' Exposure to and Engagement with Nicotine and Tobacco Product Content on Social Media.

To inform policy and messaging, this study examined characteristics of adolescents' and young adults' (AYAs') exposure to and engagement with nicotine and tobacco product (NTP) social media (SM) content. In this cross-sectional survey study, AYAs aged 13-26 (N=1,163) reported current NTP use, SM use frequency, and exposure to and engagement with SM content promoting and opposing NTP use (i.e. frequency, source[s], format[s], platform[s]). Participants who used NTPs (vs. did not use) were more likely to report having seen NTP content (p-values<.001). Prevalent sources were companies/brands (46.6%) and influencers (44.4%); prevalent formats were video (65.4%) and image (50.7%). Exposure to content promoting NTP use was prevalent on several popular platforms (e.g. TikTok, Instagram, Snapchat); exposure to content opposing NTP use was most prevalent on YouTube (75.8%). Among those reporting content engagement (i.e. liking, commenting on, or sharing NTP content; 34.6%), 57.2% engaged with influencer content. Participants reported engaging with content promoting and opposing NTP use on popular platforms (e.g. TikTok, Instagram, YouTube). Participants with (versus without) current NTP use were significantly more likely to use most SM platforms and to report NTP content exposure and engagement (p-values<.05). Results suggest that NTP education messaging and enforcement of platforms' content restrictions are needed.

Krill Oil for Knee Osteoarthritis: A Randomized Clinical Trial.

Importance: Knee osteoarthritis is disabling, with few effective treatments. Preliminary evidence suggested that krill oil supplementation improved knee pain, but effects on knee osteoarthritis remain unclear. Objective: To evaluate efficacy of krill oil supplementation, compared with placebo, on knee pain in people with knee osteoarthritis who have significant knee pain and effusion-synovitis. Design, Setting, and Participants: Multicenter, randomized, double-blind, placebo-controlled clinical trial in 5 Australian cities. Participants with clinical knee osteoarthritis, significant knee pain, and effusion-synovitis on magnetic resonance imaging were enrolled from December 2016 to June 2019; final follow-up occurred on February 7, 2020. Interventions: Participants were randomized to 2 g/d of krill oil (n = 130) or matching placebo (n = 132) for 24 weeks. Main Outcomes and Measures: The primary outcome was change in knee pain as assessed by visual analog scale (range, 0-100; 0 indicating least pain; minimum clinically important improvement = 15) over 24 weeks. Results: Of 262 participants randomized (mean age, 61.6 [SD, 9.6] years; 53% women), 222 (85%) completed the trial. Krill oil did not improve knee pain compared with placebo (mean change in VAS score, -19.9 [krill oil] vs -20.2 [placebo]; between-group mean difference, -0.3; 95% CI, -6.9 to 6.4) over 24 weeks. One or more adverse events was reported by 51% in the krill oil group (67/130) and by 54% in the placebo group (71/132). The most common adverse events were musculoskeletal and connective tissue disorders, which occurred 32 times in the krill oil group and 42 times in the placebo group, including knee pain (n = 10 with krill oil; n = 9 with placebo), lower extremity pain (n = 1 with krill oil; n = 5 with placebo), and hip pain (n = 3 with krill oil; n = 2 with placebo). Conclusions and Relevance: Among people with knee osteoarthritis who have significant knee pain and effusion-synovitis on magnetic resonance imaging, 2 g/d of daily krill oil supplementation did not improve knee pain over 24 weeks compared with placebo. These findings do not support krill oil for treating knee pain in this population. Trial Registration: Australian New Zealand Clinical Trials Registry Identifier: ACTRN12616000726459; Universal Trial Number: U1111-1181-7087.

The temporal association between adverse drug reactions and antirheumatic drugs utilisation in Western Australia: a retrospective study from real-world data (1995-2015).

BACKGROUND/OBJECTIVES: Adverse drug reactions (ADRs) can result in morbidity, mortality, and higher healthcare costs. Given the limited information available on ADRs associated with antirheumatic medications, this study aims to analyse and compare ADR reporting for these drugs in the pharmacovigilance datasets of Western Australia (WA) and the United States (US). METHODS: Therapeutic Goods Administration provided WA pharmacovigilance data of selected antirheumatic drugs to from 1995 to 2015. The proportional reporting ratio (PRR) for WA case reports was compared to corresponding USA pharmacovigilance data by assessing the disproportionality of each ADR. clinically significant or true ADRs were determined using the Evans 2001 criteria (n > 2, chi-square > 4, PRR > 2). RESULTS: A total of 232 reports were found in WA, mostly on sixty-nine women aged 45 to 69. Methotrexate, leflunomide, azathioprine, sulfasalazine, and infliximab had the highest reported ADRs, related to gastrointestinal disorders. Patients who used biological agents in WA had 2.7 times the likelihood of reporting true ADRs compared to conventional antirheumatic drugs. The ADR rates in the two datasets were comparable over the study period. CONCLUSIONS: The PRR values of ADRs were consistent between WA and US databases. Methotrexate and infliximab use were commonly associated with ADR reports in WA females, with incidence rates comparable to the US; while patients using biological agents were more likely to report true ADRs than those on conventional antirheumatic drugs in WA.

Predicting permeation of compounds across the outer membrane of P. aeruginosa using molecular descriptors.

The ability Gram-negative pathogens have at adapting and protecting themselves against antibiotics has increasingly become a public health threat. Data-driven models identifying molecular properties that correlate with outer membrane (OM) permeation and growth inhibition while avoiding efflux could guide the discovery of novel classes of antibiotics. Here we evaluate 174 molecular descriptors in 1260 antimicrobial compounds and study their correlations with antibacterial activity in Gram-negative Pseudomonas aeruginosa. The descriptors are derived from traditional approaches quantifying the compounds' intrinsic physicochemical properties, together with, bacterium-specific from ensemble docking of compounds targeting specific MexB binding pockets, and all-atom molecular dynamics simulations in different subregions of the OM model. Using these descriptors and the measured inhibitory concentrations, we design a statistical protocol to identify predictors of OM permeation/inhibition. We find consistent rules across most of our data highlighting the role of the interaction between the compounds and the OM. An implementation of the rules uncovered in our study is shown, and it demonstrates the accuracy of our approach in a set of previously unseen compounds. Our analysis sheds new light on the key properties drug candidates need to effectively permeate/inhibit P. aeruginosa, and opens the gate to similar data-driven studies in other Gram-negative pathogens.

Exploring current physiotherapy practices in the care of people who are potential lung donors: A qualitative study.

OBJECTIVE: The aim of this study was to determine physiotherapists' current practices and perspectives regarding their role in caring for people who are potential lung donors in the intensive care unit (ICU). METHODS: A qualitative descriptive design was used. Qualitative data were collected through audio-recorded, semistructured focus groups with a purposive sample of physiotherapists with experience working with people who are potential lung donors in ICUs. Two investigators completed independent thematic analysis to identify themes. RESULTS: Seven focus groups were completed with 27 physiotherapists at six metropolitan health services in Victoria, Australia. Six key themes were identified: (i) physiotherapists' involvement in care was highly variable; (ii) physiotherapists were not aware of existing evidence or guidelines for the care of people who are potential donors and followed usual practices; (iii) a consistent vision of the physiotherapy role was lacking; (iv) physiotherapists' engagement with the team routinely involved in care of people who are potential donors varied considerably; (v) physiotherapists faced practice challenges associated with delivering care to potential donors; and (vi) several enablers could support a role for physiotherapy in this patient population. CONCLUSIONS: Variability in physiotherapy practice is associated with local ICU culture, physiotherapy leadership capabilities, knowledge, and experience. The spectrum of practice ranged from physiotherapists being highly engaged to being completely uninvolved. Physiotherapists held mixed perspectives regarding whether physiotherapists should have a role in managing people who are potential lung donors. It would benefit the profession to develop consensus and standardisation of the role of physiotherapists in caring for these patients. TWEETABLE ABSTRACT: Variability in views and practices amongst physiotherapists who provide care to patients who are potential lung donors in the ICU.

Population-wide long-term study of incidence, renal failure, and mortality rates for lupus nephritis.

OBJECTIVE: Given limited regional data, we investigate the state-wide epidemiology, renal and patient outcomes for lupus nephritis (LN) in Western Australia (WA). METHODS: Patients hospitalized with incident SLE (≥2 diagnostic codes in the state-wide WA Health Hospital Morbidity Data Collection) in the period 1985-2015 were included (n = 1480). LN was defined by the presence of glomerulonephritis and/or raised serum creatinine. Trends over three study decades for annual incidence rate (AIR)/100.000 population, mortality (MR), and end-stage renal disease (ESRD) rates/100 person years were analyzed by least square regression and compared with a matched control group (n = 12 840). RESULTS: Clinical evidence of LN developed in 366 SLE patients (25.9%) after a median disease duration of 10 months (IQR 0-101) with renal biopsy performed in 308 (84.2%). The AIR for LN (0.63/100.000) did not change significantly over time (R2 = .11, p = .85), while point prevalence reached 11.9/100.000 in 2015. ESRD developed in 14.1% (n = 54) of LN patients vs. 0.2% in non-LN SLE patients and 0.05% in controls (all p ≤ 0.01). ESRD rates increased over time in LN patients (0.4 to 0.7, R2 = .52, p = .26). The odds ratio for death was 8.81 (CI 3.78-22.9) for LN and 6.62 (CI 2.76-17.9) for non-LN SLE patients compared to controls and MR for LN patients increased over time (1.3 to 2.2, R2 = .84, p = .26). CONCLUSIONS: The incidence rate of LN in WA remained unchanged over 30 years. A lack of improvement in renal failure and mortality rates illustrates the pressing need for better long-term treatment options and/or strategies in LN.

The longitudinal study of muscle changes with ultrasound: differential changes in idiopathic inflammatory myopathy subgroups.

OBJECTIVES: We investigated shear wave elastography (SWE), B mode US and power Doppler (PDUS) as imaging biomarkers for longitudinal follow-up in idiopathic inflammatory myopathy (IIM), with a particular focus on immune-mediated necrotizing myopathy (IMNM) and DM. METHODS: Participants had serial SWE, PDUS on the deltoid (D) and vastus lateralis (VL) muscles on four occasions at intervals of 3-6 months. Clinical assessments included manual muscle testing, and patient- and physician-reported outcome scales. RESULTS: Thirty-three participants were included: IMNM = 17, DM = 12, overlap myositis = 3, PM = 1. Twenty were in a prevalent clinic group, and 13 were recently treated cases in an incident group. Differential changes in SWS and US domains occurred with time in both the prevalent and incident groups. In the VL-prevalent subgroup, echogenicity increased over time (P = 0.040), while in the incident cases there was a trend for reduction to normal over time (P = 0.097) with treatment. Muscle bulk reduced in the D-prevalent subgroup over time (P = 0.096), suggesting atrophy. SWS also reduced in the VL-incident subgroup over time (P = 0.096), suggesting a trend towards improvement in muscle stiffness with treatment. CONCLUSION: SWE and US appear promising as imaging biomarkers for patient follow-up in IIM and indicate changes over time, especially with echogenicity, muscle bulk and SWS in the VL. Due to the limitations of the participant numbers, additional studies with a larger cohort are needed to help evaluate these US domains further and outline specific characteristics within the IIM subgroups.

How megadrought causes extensive mortality in a deep-rooted shrub species normally resistant to drought-induced dieback: The role of a biotic mortality agent.

Southern California experienced unprecedented megadrought between 2012 and 2018. During this time, Malosma laurina, a chaparral species normally resilient to single-year intense drought, developed extensive mortality exceeding 60% throughout low-elevation coastal populations of the Santa Monica Mountains. We assessed the physiological mechanisms by which the advent of megadrought predisposed M. laurina to extensive shoot dieback and whole-plant death. We found that hydraulic conductance of stem xylem (Ks, native ) was reduced seven to 11-fold in dieback adult and resprout branches, respectively. Staining of stem xylem vessels revealed that dieback plants experienced 68% solid-blockage, explaining the reduction in water transport. Following Koch's postulates, persistent isolation of a microorganism in stem xylem of dieback plants but not healthy controls indicated that the causative agent of xylem blockage was an opportunistic endophytic fungus, Botryosphaeria dothidea. We inoculated healthy M. laurina saplings with fungal isolates and compared hyphal elongation rates under well-watered, water-deficit, and carbon-deficit treatments. Relative to controls, we found that both water deficit and carbon-deficit increased hyphal extension rates and the incidence of shoot dieback.

A longitudinal study using B mode ultrasound and power Doppler as monitoring imaging tools in inclusion body myositis.

OBJECTIVES: There is growing interest in ultrasound (US) as an outcome measure in IBM. Our study aimed to determine the ability of B mode US and power Doppler (PD) to detect changes in affected muscles over time and if US domains correlate with disease progression. METHODS: Participants attended on four occasions over a median follow-up period of 26 months. All completed a patient self-reported health assessment questionnaire (HAQ), patient visual analogue scale (pVAS), manual muscle testing (MMT), and US (fascial thickness-FT, muscle bulk, echogenicity, and PD) on deltoid and vastus lateralis (VL) muscles at each visit. RESULTS: This longitudinal observational study had 35 participants: 21 (60%) males, median age 70 (IQR (64-76), and the majority (85.7%) not on immunosuppression. When analysed for sex differences at baseline, males had lower FT-VL (p=0.018) and higher muscle bulk (p=0.002) than females. Only FT-deltoid (p<0.001) increased significantly over time with follow-up. When participants were stratified into progressors and non-progressors, FT at baseline was lower in progressors (0.06 vs. 0.09, p=0.017), who were predominantly male. There were no significant differences in other US domains. CONCLUSIONS: Our study highlights previously unreported sex differences in US findings in IBM. Certain US domains, such as FT, showed measurable changes over time and correlated with disease progression. However, further studies with longer follow-up periods and larger patient cohorts will need to be performed to determine whether B mode US could be a useful disease outcome measure for therapeutic trials.

Nonadditive functional interactions between ligand-binding sites of the multidrug efflux pump AdeB from Acinetobacter baumannii.

Multidrug efflux is one of the major mechanisms of antibiotic resistance identified in clinical isolates of the human pathogen Acinetobacter baumannii. The multiple antibiotic resistance in this species is often enabled by the overproduction of the tripartite efflux pump AdeABC. In this pump, AdeB is the inner membrane transporter from the resistance-nodulation-division (RND) superfamily of proteins, which is responsible for the recognition and efflux of multiple structurally unrelated compounds. Like other RND transporters, AdeB is a trimeric protein with ligand-binding sites located in the large periplasmic domains. Previous structural studies, however, highlighted the uniqueness of AdeB interactions with ligands. Up to three ligand molecules were bound to one protomer of AdeB, mapping its substrate translocation path. In this study, we introduced single and double substitutions in the identified ligand-binding sites of AdeB. Our results show that the mechanism of substrate translocation by AdeB is different from that of other characterized RND transporters and that the functional interactions between the sites are nonadditive. We identified AdeB mutants with both the loss and the gain of antibiotic susceptibility phenotypes, as well as AdeB mutations making A. baumannii cells overproducing such pump variants even more susceptible to multiple antibiotics than efflux-deficient cells. IMPORTANCE Multidrug efflux pumps of the resistance-nodulation-division superfamily of proteins are important contributors to various aspects of bacterial physiology and antibiotic resistance. Studies of the best-characterized model transporter AcrB from Escherichia coli suggested that these transporters operate by a functional rotation mechanism in which various substrates bind to at least two different binding sites. This study suggests that the mechanism of AdeB is distinct and that the binding sites in this transporter are functionally linked.

21st century (clinical) decision support in nursing and allied healthcare. Developing a learning health system: a reasoned design of a theoretical framework.

In this paper, we present a framework for developing a Learning Health System (LHS) to provide means to a computerized clinical decision support system for allied healthcare and/or nursing professionals. LHSs are well suited to transform healthcare systems in a mission-oriented approach, and is being adopted by an increasing number of countries. Our theoretical framework provides a blueprint for organizing such a transformation with help of evidence based state of the art methodologies and techniques to eventually optimize personalized health and healthcare. Learning via health information technologies using LHS enables users to learn both individually and collectively, and independent of their location. These developments demand healthcare innovations beyond a disease focused orientation since clinical decision making in allied healthcare and nursing is mainly based on aspects of individuals' functioning, wellbeing and (dis)abilities. Developing LHSs depends heavily on intertwined social and technological innovation, and research and development. Crucial factors may be the transformation of the Internet of Things into the Internet of FAIR data & services. However, Electronic Health Record (EHR) data is in up to 80% unstructured including free text narratives and stored in various inaccessible data warehouses. Enabling the use of data as a driver for learning is challenged by interoperability and reusability.To address technical needs, key enabling technologies are suitable to convert relevant health data into machine actionable data and to develop algorithms for computerized decision support. To enable data conversions, existing classification and terminology systems serve as definition providers for natural language processing through (un)supervised learning.To facilitate clinical reasoning and personalized healthcare using LHSs, the development of personomics and functionomics are useful in allied healthcare and nursing. Developing these omics will be determined via text and data mining. This will focus on the relationships between social, psychological, cultural, behavioral and economic determinants, and human functioning.Furthermore, multiparty collaboration is crucial to develop LHSs, and man-machine interaction studies are required to develop a functional design and prototype. During development, validation and maintenance of the LHS continuous attention for challenges like data-drift, ethical, technical and practical implementation difficulties is required.

Methotrexate to treat hand osteoarthritis with synovitis (METHODS): an Australian, multisite, parallel-group, double-blind, randomised, placebo-controlled trial.

BACKGROUND: Hand osteoarthritis is a disabling condition with few effective therapies. Hand osteoarthritis with synovitis is a common inflammatory phenotype associated with pain. We aimed to examine the efficacy and safety of methotrexate at 6 months in participants with hand osteoarthritis and synovitis. METHODS: In this multisite, parallel-group, double-blind, randomised, placebo-controlled trial, participants (aged 40-75 years) with hand osteoarthritis (Kellgren and Lawrence grade ≥2 in at least one joint) and MRI-detected synovitis of grade 1 or more were recruited from the community in Melbourne, Hobart, Adelaide, and Perth, Australia. Participants were randomly assigned (1:1) using block randomisation, stratified by study site and self-reported sex, to receive methotrexate 20 mg or identical placebo orally once weekly for 6 months. The primary outcome was pain reduction (measured with a 100 mm visual analogue scale; VAS) in the study hand at 6 months assessed in the intention-to-treat population. Safety outcomes were assessed in all randomly assigned participants. This trial was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12617000877381). FINDINGS: Between Nov 22, 2017, and Nov 8, 2021, of 202 participants who were assessed for eligibility, 97 (48%) were randomly assigned to receive methotrexate (n=50) or placebo (n=47). 68 (70%) of 97 participants were female and 29 (30%) were male. 42 (84%) of 50 participants in the methotrexate group and 40 (85%) of 47 in the placebo group provided primary outcome data. The mean change in VAS pain at 6 months was -15·2 mm (SD 24·0) in the methotrexate group and -7·7 mm (25·3) in the placebo group, with a mean between-group difference of -9·9 (95% CI -19·3 to -0·6; p=0·037) and an effect size (standardised mean difference) of 0·45 (0·03 to 0·87). Adverse events occurred in 31 (62%) of 50 participants in the methotrexate group and 28 (60%) of 47 participants in the placebo group. INTERPRETATION: Treatment of hand osteoarthritis and synovitis with 20 mg methotrexate for 6 months had a moderate but potentially clinically meaningful effect on reducing pain, providing proof of concept that methotrexate might have a role in the management of hand osteoarthritis with an inflammatory phenotype. FUNDING: National Health and Medical Research Council of Australia.

The risk of acute kidney injury in colorectal cancer survivors: an english population-based matched cohort study.

BACKGROUND: Colorectal cancer survival has improved in recent decades but there are concerns that survivors may develop kidney problems due to adverse effects of cancer treatment or complications of the cancer itself. We quantified the risk of acute kidney injury (AKI) in colorectal cancer survivors compared to people with no prior cancer. METHODS: Retrospective matched cohort study using electronic health record primary care data from the Clinical Practice Research Datalink GOLD linked to hospital data in England (HES-APC). Individuals with colorectal cancer between 1997-2018 were individually matched on age, sex, and GP practice to people with no prior cancer. We used Cox models to estimate hazard ratios for an incident hospital diagnosis of AKI in colorectal cancer survivors compared to individuals without cancer, overall and stratified by time since diagnosis adjusted for other individual-level factors (adj-HR). RESULTS: Twenty thousand three hundred forty colorectal cancer survivors were matched to 100,058 cancer-free individuals. Colorectal cancer survivors were at increased risk of developing AKI compared to people without cancer (adj-HR = 2.16; 95%CI 2.05-2.27). The HR was highest in the year after diagnosis (adj-HR 7.47, 6.66-8.37), and attenuated over time, but there was still increased AKI risk > 5 years after diagnosis (adj-HR = 1.26, 1.17-1.37). The association between colorectal cancer and AKI was greater for younger people, men, and those with pre-existing chronic kidney disease. CONCLUSIONS: Colorectal cancer survivors were at increased risk of AKI for several years after cancer diagnosis, suggesting a need to prioritise monitoring, prevention, and management of kidney problems in this group of cancer survivors.

Binding of the nuclear ribonucleoprotein family member FUS to RNA prevents R-loop RNA:DNA hybrid structures.

The protein FUS (FUSed in sarcoma) is a metazoan RNA-binding protein that influences RNA production by all three nuclear polymerases. FUS also binds nascent transcripts, RNA processing factors, RNA polymerases, and transcription machinery. Here, we explored the role of FUS binding interactions for activity during transcription. In vitro run-off transcription assays revealed FUS-enhanced RNA produced by a non-eukaryote polymerase. The activity also reduced the formation of R-loops between RNA products and their DNA template. Analysis by domain mutation and deletion indicated RNA-binding was required for activity. We interpret that FUS binds and sequesters nascent transcripts to prevent R-loops from forming with nearby DNA. DRIP-seq analysis showed that a knockdown of FUS increased R-loop enrichment near expressed genes. Prevention of R-loops by FUS binding to nascent transcripts has the potential to affect transcription by any RNA polymerase, highlighting the broad impact FUS can have on RNA metabolism in cells and disease.