ARF family G proteins and their regulators: roles in membrane transport, development and disease.

Members of the ADP-ribosylation factor (ARF) family of guanine-nucleotide-binding (G) proteins, including the ARF-like (ARL) proteins and SAR1, regulate membrane traffic and organelle structure by recruiting cargo-sorting coat proteins, modulating membrane lipid composition, and interacting with regulators of other G proteins. New roles of ARF and ARL proteins are emerging, including novel functions at the Golgi complex and in cilia formation. Their function is under tight spatial control, which is mediated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs) that catalyse GTP exchange and hydrolysis, respectively. Important advances are being gained in our understanding of the functional networks that are formed not only by the GEFs and GAPs themselves but also by the inactive forms of the ARF proteins.

RNA Profiles of Tear Fluid Extracellular Vesicles in Patients with Dry Eye-Related Symptoms.

Currently, diagnosing and stratifying dry eye disease (DED) require multiple tests, motivating interest in a single definitive test. The purpose of this study was to investigate the potential for using tear fluid extracellular vesicle (EV)-RNA in DED diagnostics. With a role in intercellular communication, nanosized EVs facilitate the protected transport of diverse bioactive molecules in biofluids, including tears. Schirmer strips were used to collect tears from 10 patients presenting with dry eye-related symptoms at the Norwegian Dry Eye Clinic. The samples comprised two groups, five from patients with a tear film break-up time (TBUT) of 2 s and five from patients with a TBUT of 10 s. Tear fluid EV-RNA was isolated using a Qiagen exoRNeasy Midi Kit, and the RNA was characterized using Affymetrix ClariomTM D microarrays. The mean signal values of the two groups were compared using a one-way ANOVA. A total of 26,639 different RNA transcripts were identified, comprising both mRNA and ncRNA subtypes. Approximately 6% of transcripts showed statistically significant differential abundance between the two groups. The mRNA sodium channel modifier 1 (SCNM1) was detected at a level 3.8 times lower, and the immature microRNA-130b was detected at a level 1.5 times higher in the group with TBUT 2 s compared to the group with TBUT 10 s. This study demonstrates the potential for using tear fluid EV-RNA in DED diagnostics.

Is the "end-of-study guess" a valid measure of sham blinding during transcranial direct current stimulation?

Studies using transcranial direct current stimulation (tDCS) typically incorporate a fade-in, short-stimulation, fade-out sham (placebo) protocol, which is assumed to be indistinct from a 10-30 min active protocol on the scalp. However, many studies report that participants can dissociate active stimulation from sham, even during low-intensity 1 mA currents. We recently identified differences in the perception of an active (10 min of 1 mA) and a sham (20 s of 1 mA) protocol that lasted for 5 min after the cessation of sham. In the present study we assessed whether delivery of a higher-intensity 2 mA current would exacerbate these differences. Two protocols were delivered to 32 adults in a double-blinded, within-subjects design (active: 10 min of 2 mA, and sham: 20 s of 2 mA), with the anode over the left primary motor cortex and the cathode on the right forehead. Participants were asked "Is the stimulation on?" and "How sure are you?" at 30 s intervals during and after stimulation. The differences between active and sham were more consistent and sustained during 2 mA than during 1 mA. We then quantified how well participants were able to track the presence and absence of stimulation (i.e. their sensitivity) during the experiment using cross-correlations. Current strength was a good classifier of sensitivity during active tDCS, but exhibited only moderate specificity during sham. The accuracy of the end-of-study guess was no better than chance at predicting sensitivity. Our results indicate that the traditional end-of-study guess poorly reflects the sensitivity of participants to stimulation, and may not be a valid method of assessing sham blinding.

Functional and Physical Interaction between the Arf Activator GBF1 and Hepatitis C Virus NS3 Protein.

GBF1 has emerged as a host factor required for the genome replication of RNA viruses of different families. During the hepatitis C virus (HCV) life cycle, GBF1 performs a critical function at the onset of genome replication but is dispensable when the replication is established. To better understand how GBF1 regulates HCV infection, we have looked for interactions between GBF1 and HCV proteins. NS3 was found to interact with GBF1 in yeast two-hybrid, coimmunoprecipitation, and proximity ligation assays and to interfere with GBF1 function and alter GBF1 intracellular localization in cells expressing NS3. The interaction was mapped to the Sec7 domain of GBF1 and the protease domain of NS3. A reverse yeast two-hybrid screen to identify mutations altering NS3-GBF1 interaction yielded an NS3 mutant (N77D, Con1 strain) that is nonreplicative despite conserved protease activity and does not interact with GBF1. The mutated residue is exposed at the surface of NS3, suggesting it is part of the domain of NS3 that interacts with GBF1. The corresponding mutation in strain JFH-1 (S77D) produces a similar phenotype. Our results provide evidence for an interaction between NS3 and GBF1 and suggest that an alteration of this interaction is detrimental to HCV genome replication.IMPORTANCE Single-stranded, positive-sense RNA viruses rely to a significant extent on host factors to achieve the replication of their genome. GBF1 is such a cellular protein that is required for the replication of several RNA viruses, but its mechanism of action during viral infections is not yet defined. In this study, we investigated potential interactions that GBF1 might engage in with proteins of HCV, a GBF1-dependent virus. We found that GBF1 interacts with NS3, a nonstructural protein involved in HCV genome replication, and our results suggest that this interaction is important for GBF1 function during HCV replication. Interestingly, GBF1 interaction with HCV appears different from its interaction with enteroviruses, another group of GBF1-dependent RNA viruses, in keeping with the fact that HCV and enteroviruses use different functions of GBF1.

Sericin-Induced Melanogenesis in Cultured Retinal Pigment Epithelial Cells Is Associated with Elevated Levels of Hydrogen Peroxide and Inflammatory Proteins.

We previously demonstrated that the silk protein sericin promotes pigmentation of retinal pigment epithelium (RPE) by activating the NF-κB pathway. Among numerous agents, NF-κB can be activated by hydrogen peroxide. In the present study, we explored possible associations between reactive oxygen species and sericin-induced melanogenesis in RPE. The proteome of human fetal RPE cultured for seven days with or without 1% sericin was analyzed using ingenuity pathway analysis (IPA). The proteomic data was verified by immunofluorescence and immunoblotting. Light microscopy and scanning electron microscopy were used to assess morphology. Dihydroethidium (DHE) and dihydrorhodamine (DHR) assays were used to measure superoxide and hydrogen peroxide species. Expression levels of proteins related to inflammation, differentiation, cell survival and cell adhesion were higher in cells cultured in Dulbecco's Modified Eagle Medium (DMEM) with 1% sericin, whereas cells cultured in DMEM alone showed higher expression levels of proteins associated with Bruch's membrane and cytoskeleton. Despite upregulation of inflammatory proteins, sericin co-cultured RPE yielded significantly higher cell viability compared to cells cultured without sericin. Addition of sericin to culture media significantly increased hydrogen peroxide-levels without significantly affecting superoxide-levels. We suggest that sericin-induced melanogenesis in cultured RPE is associated with elevated levels of superoxide dismutase, hydrogen peroxide and inflammatory proteins.

Identification of GBF1 as a cellular factor required for hepatitis E virus RNA replication.

The hepatitis E virus (HEV) genome is a single-stranded, positive-sense RNA that encodes three proteins including the ORF1 replicase. Mechanisms of HEV replication in host cells are unclear, and only a few cellular factors involved in this step have been identified so far. Here, we used brefeldin A (BFA) that blocks the activity of the cellular Arf guanine nucleotide exchange factors GBF1, BIG1, and BIG2, which play a major role in reshuffling of cellular membranes. We showed that BFA inhibits HEV replication in a dose-dependent manner. The use of siRNA and Golgicide A identified GBF1 as a host factor critically involved in HEV replication. Experiments using cells expressing a mutation in the catalytic domain of GBF1 and overexpression of wild type GBF1 or a BFA-resistant GBF1 mutant rescuing HEV replication in BFA-treated cells, confirmed that GBF1 is the only BFA-sensitive factor required for HEV replication. We demonstrated that GBF1 is likely required for the activity of HEV replication complexes. However, GBF1 does not colocalise with the ORF1 protein, and its subcellular distribution is unmodified upon infection or overexpression of viral proteins, indicating that GBF1 is likely not recruited to replication sites. Together, our results suggest that HEV replication involves GBF1-regulated mechanisms.

ORP5/ORP8 localize to endoplasmic reticulum-mitochondria contacts and are involved in mitochondrial function.

The oxysterol-binding protein (OSBP)-related proteins ORP5 and ORP8 have been shown recently to transport phosphatidylserine (PS) from the endoplasmic reticulum (ER) to the plasma membrane (PM) at ER-PM contact sites. PS is also transferred from the ER to mitochondria where it acts as precursor for mitochondrial PE synthesis. Here, we show that, in addition to ER-PM contact sites, ORP5 and ORP8 are also localized to ER-mitochondria contacts and interact with the outer mitochondrial membrane protein PTPIP51. A functional lipid transfer (ORD) domain was required for this localization. Interestingly, ORP5 and ORP8 depletion leads to defects in mitochondria morphology and respiratory function.

GBF1 and Arf1 function in vesicular trafficking, lipid homoeostasis and organelle dynamics.

The ADP-ribosylation factor (Arf) small G proteins act as molecular switches to coordinate multiple downstream pathways that regulate membrane dynamics. Their activation is spatially and temporally controlled by the guanine nucleotide exchange factors (GEFs). Members of the evolutionarily conserved GBF/Gea family of Arf GEFs are well known for their roles in formation of coat protein complex I (COPI) vesicles, essential for maintaining the structure and function of the Golgi apparatus. However, studies over the past 10 years have found new functions for these GEFs, along with their substrate Arf1, in lipid droplet metabolism, clathrin-independent endocytosis, signalling at the plasma membrane, mitochondrial dynamics and transport along microtubules. Here, we describe these different functions, focussing in particular on the emerging theme of GFB1 and Arf1 regulation of organelle movement on microtubules.

Strategies to improve recruitment to randomised trials.

BACKGROUND: Recruiting participants to trials can be extremely difficult. Identifying strategies that improve trial recruitment would benefit both trialists and health research. OBJECTIVES: To quantify the effects of strategies for improving recruitment of participants to randomised trials. A secondary objective is to assess the evidence for the effect of the research setting (e.g. primary care versus secondary care) on recruitment. SEARCH METHODS: We searched the Cochrane Methodology Review Group Specialised Register (CMR) in the Cochrane Library (July 2012, searched 11 February 2015); MEDLINE and MEDLINE In Process (OVID) (1946 to 10 February 2015); Embase (OVID) (1996 to 2015 Week 06); Science Citation Index & Social Science Citation Index (ISI) (2009 to 11 February 2015) and ERIC (EBSCO) (2009 to 11 February 2015). SELECTION CRITERIA: Randomised and quasi-randomised trials of methods to increase recruitment to randomised trials. This includes non-healthcare studies and studies recruiting to hypothetical trials. We excluded studies aiming to increase response rates to questionnaires or trial retention and those evaluating incentives and disincentives for clinicians to recruit participants. DATA COLLECTION AND ANALYSIS: We extracted data on: the method evaluated; country in which the study was carried out; nature of the population; nature of the study setting; nature of the study to be recruited into; randomisation or quasi-randomisation method; and numbers and proportions in each intervention group. We used a risk difference to estimate the absolute improvement and the 95% confidence interval (CI) to describe the effect in individual trials. We assessed heterogeneity between trial results. We used GRADE to judge the certainty we had in the evidence coming from each comparison. MAIN RESULTS: We identified 68 eligible trials (24 new to this update) with more than 74,000 participants. There were 63 studies involving interventions aimed directly at trial participants, while five evaluated interventions aimed at people recruiting participants. All studies were in health care.We found 72 comparisons, but just three are supported by high-certainty evidence according to GRADE.1. Open trials rather than blinded, placebo trials. The absolute improvement was 10% (95% CI 7% to 13%).2. Telephone reminders to people who do not respond to a postal invitation. The absolute improvement was 6% (95% CI 3% to 9%). This result applies to trials that have low underlying recruitment. We are less certain for trials that start out with moderately good recruitment (i.e. over 10%).3. Using a particular, bespoke, user-testing approach to develop participant information leaflets. This method involved spending a lot of time working with the target population for recruitment to decide on the content, format and appearance of the participant information leaflet. This made little or no difference to recruitment: absolute improvement was 1% (95% CI -1% to 3%).We had moderate-certainty evidence for eight other comparisons; our confidence was reduced for most of these because the results came from a single study. Three of the methods were changes to trial management, three were changes to how potential participants received information, one was aimed at recruiters, and the last was a test of financial incentives. All of these comparisons would benefit from other researchers replicating the evaluation. There were no evaluations in paediatric trials.We had much less confidence in the other 61 comparisons because the studies had design flaws, were single studies, had very uncertain results or were hypothetical (mock) trials rather than real ones. AUTHORS' CONCLUSIONS: The literature on interventions to improve recruitment to trials has plenty of variety but little depth. Only 3 of 72 comparisons are supported by high-certainty evidence according to GRADE: having an open trial and using telephone reminders to non-responders to postal interventions both increase recruitment; a specialised way of developing participant information leaflets had little or no effect. The methodology research community should improve the evidence base by replicating evaluations of existing strategies, rather than developing and testing new ones.

Interdigitation between Triglycerides and Lipids Modulates Surface Properties of Lipid Droplets.

Intracellular lipid droplets (LDs) are the main cellular site of metabolic energy storage. Their structure is unique inside the cell, with a core of esterified fatty acids and sterols, mainly triglycerides and sterol esters, surrounded by a single monolayer of phospholipids. Numerous peripheral proteins, including several that were previously associated with intracellular compartments surrounded by a lipid bilayer, have been recently shown to target the surface of LDs, but how they are able to selectively target this organelle remains largely unknown. Here, we use atomistic and coarse-grained molecular dynamics simulations to investigate the molecular properties of the LD surface and to characterize how it differs from that of a lipid bilayer. Our data suggest that although several surface properties are remarkably similar between the two structures, key differences originate from the interdigitation between surface phospholipids and core neutral lipids that occurs in LDs. This property is extremely sensitive to membrane undulations, unlike in lipid bilayers, and it strongly affects both lipid-packing defects and the lateral pressure profile. We observed a marked change in overall surface properties for surface tensions >10 mN/m, indicative of a bimodal behavior. Our simulations provide a comprehensive molecular characterization of the unique surface properties of LDs and suggest how the molecular properties of the surface lipid monolayer can be modulated by the underlying neutral lipids.

Identification of class II ADP-ribosylation factors as cellular factors required for hepatitis C virus replication.

GBF1 is a host factor required for hepatitis C virus (HCV) replication. GBF1 functions as a guanine nucleotide exchange factor for G-proteins of the Arf family, which regulate membrane dynamics in the early secretory pathway and the metabolism of cytoplasmic lipid droplets. Here we established that the Arf-guanine nucleotide exchange factor activity of GBF1 is critical for its function in HCV replication, indicating that it promotes viral replication by activating one or more Arf family members. Arf involvement was confirmed with the use of two dominant negative Arf1 mutants. However, siRNA-mediated depletion of Arf1, Arf3 (class I Arfs), Arf4 or Arf5 (class II Arfs), which potentially interact with GBF1, did not significantly inhibit HCV infection. In contrast, the simultaneous depletion of both Arf4 and Arf5, but not of any other Arf pair, imposed a significant inhibition of HCV infection. Interestingly, the simultaneous depletion of both Arf4 and Arf5 had no impact on the activity of the secretory pathway and induced a compaction of the Golgi and an accumulation of lipid droplets. A similar phenotype of lipid droplet accumulation was also observed when GBF1 was inhibited by brefeldin A. In contrast, the simultaneous depletion of both Arf1 and Arf4 resulted in secretion inhibition and Golgi scattering, two actions reminiscent of GBF1 inhibition. We conclude that GBF1 could regulate different metabolic pathways through the activation of different pairs of Arf proteins.

Acute rheumatic fever and exposure to poor housing conditions in New Zealand: A descriptive study.

AIM: Acute rheumatic fever (ARF) is an important public health problem in low- and middle-income countries and in certain populations in high-income countries. Indigenous Australians, and New Zealand Maori and Pacific people, have incidence rates among the highest in the world. We aimed to investigate ARF cases' housing conditions and sore throat treatment to identify opportunities for improving ARF prevention in New Zealand. METHODS: Recently diagnosed cases and their care givers were interviewed. Information was obtained about the cases' demographics, housing circumstances and conditions, and sore throat treatment preceding ARF. RESULTS: We interviewed 55 cases. Most (75%) lived in rental housing and reported multiple measures of deprivation. Common exposures were household crowding (58%), bed-sharing (49%), dampness and mould (76%), cold (82%) and co-habiting with smokers (71%). Experiencing sore throat in the weeks before ARF was recalled by 62%, with 29% seeing a doctor or nurse and 13% of the total sample receiving antibiotics. CONCLUSIONS: The environmental conditions reported could contribute to high group A Streptococcus transmission and susceptibility to infection, thus increasing ARF risk. Sore throat treatment has important limitations as an intervention, particularly as 38% of participants did not recall sore throat preceding the diagnosis. The results support the need to improve rental housing. Interventions promoting minimum enforceable standards in social housing and private rental sectors (such as a housing warrant of fitness) could support these changes. A rigorous investigation, such as a case control study, is needed to explore risk factors further.

Neonatal invasive pneumococcal disease: New Zealand experience in the era of pneumococcal vaccination.

BACKGROUND: Invasive pneumococcal disease (IPD) became a notifiable disease in New Zealand in 2008, and in the same year pneumococcal conjugate vaccine (PCV) was added to the childhood immunisation schedule. DESIGN: This was a retrospective study of IPD in infants aged <90 days reported to the national notifiable disease database, EpiSurv, from 1 January 2009 to 31 December 2013. All cases had Streptococcus pneumoniae isolated from a normally sterile site. MAIN OUTCOME MEASURES: IPD incidence was calculated for babies aged <90 and <30 days using the number of national IPD cases with a denominator of annual infant live births. Clinical, demographic and outcome data were reviewed for infants aged less than seven days (early onset). RESULTS: There were 29 cases of IPD in infants aged <90 days and 19 cases in infants aged <30 days. Of the nine early-onset cases, six occurred within the first 48 h. Six of the early-onset cases were infants of NZ Maori ethnicity. One infant died six hours after birth. Three infants developed long-term neurological or respiratory sequelae. Isolates from five of the early-onset cases were S. pneumoniae serotypes not covered by the PCV in use at the time of infection. Maternal vaccination with 23-valent pneumococcal vaccine would have covered 84% (16 of 19) of serotypes responsible for the cases in infants <30 days old. CONCLUSION: Strategies such as maternal vaccination or accelerated neonatal vaccination may be beneficial to protect neonates at high risk of IPD.

Arfs at a glance.

The Arf small G proteins regulate protein and lipid trafficking in eukaryotic cells through a regulated cycle of GTP binding and hydrolysis. In their GTP-bound form, Arf proteins recruit a specific set of protein effectors to the membrane surface. These effectors function in vesicle formation and tethering, non-vesicular lipid transport and cytoskeletal regulation. Beyond fundamental membrane trafficking roles, Arf proteins also regulate mitosis, plasma membrane signaling, cilary trafficking and lipid droplet function. Tight spatial and temporal regulation of the relatively small number of Arf proteins is achieved by their guanine nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs), which catalyze GTP binding and hydrolysis, respectively. A unifying function of Arf proteins, performed in conjunction with their regulators and effectors, is sensing, modulating and transporting the lipids that make up cellular membranes. In this Cell Science at a Glance article and the accompanying poster, we discuss the unique features of Arf small G proteins, their functions in vesicular and lipid trafficking in cells, and how these functions are modulated by their regulators, the GEFs and GAPs. We also discuss how these Arf functions are subverted by human pathogens and disease states.

Nucleus Morphometry in Cultured Epithelial Cells Correlates with Phenotype.

Phenotype of cultured ocular epithelial transplants has been shown to affect clinical success rates following transplantation to the cornea. The purpose of this study was to evaluate the relationship between cell nucleus morphometry and phenotype in three types of cultured epithelial cells. This study provides knowledge for the development of a non-invasive method of determining the phenotype of cultured epithelium before transplantation. Cultured human conjunctival epithelial cells (HCjE), human epidermal keratinocytes (HEK), and human retinal pigment epithelial cells (HRPE) were analyzed by quantitative immunofluorescence. Assessments of nucleus morphometry and nucleus-to-cytoplasm ratio (N/C ratio) were performed using ImageJ. Spearman's correlation coefficient was employed for statistical analysis. Levels of the proliferation marker PCNA in HCjE, HEK, and HRPE correlated positively with nuclear area. Nuclear area correlated significantly with levels of the undifferentiated cell marker ABCG2 in HCjE. Bmi1 levels, but not p63α levels, correlated significantly with nuclear area in HEK. The N/C ratio did not correlate significantly with any of the immunomarkers in HCjE (ABCG2, CK7, and PCNA) and HRPE (PCNA). In HEK, however, the N/C ratio was negatively correlated with levels of the undifferentiated cell marker CK14 and positively correlated with Bmi1 expression. The size of the nuclear area correlated positively with proliferation markers in all three epithelia. Morphometric indicators of phenotype in cultured epithelia can be identified using ImageJ. Conversely, the N/C ratio did not show a uniform relationship with phenotype in HCjE, HEK, or HRPE. N/C ratio therefore, may not be a useful morphometric marker for in vitro assessment of phenotype in these three epithelia.

Targeting of the Arf-GEF GBF1 to lipid droplets and Golgi membranes.

Lipid droplet metabolism and secretory pathway trafficking both require activation of the Arf1 small G protein. The spatiotemporal regulation of Arf1 activation is mediated by guanine nucleotide exchange factors (GEFs) of the GBF and BIG families, but the mechanisms of their localization to multiple sites within cells are poorly understood. Here we show that GBF1 has a lipid-binding domain (HDS1) immediately downstream of the catalytic Sec7 domain, which mediates association with both lipid droplets and Golgi membranes in cells, and with bilayer liposomes and artificial droplets in vitro. An amphipathic helix within HDS1 is necessary and sufficient for lipid binding, both in vitro and in cells. The HDS1 domain of GBF1 is stably associated with lipid droplets in cells, and the catalytic Sec7 domain inhibits this potent lipid-droplet-binding capacity. Additional sequences upstream of the Sec7 domain-HDS1 tandem are required for localization to Golgi membranes. This mechanism provides insight into crosstalk between lipid droplet function and secretory trafficking.

Meeting report - Arf and Rab family G proteins.

A FASEB Summer Research Conference entitled 'Arf and Rab family G proteins' was held in July 2013 at Snowmass Village, Snowmass, Colorado. Arfs and Rabs are two families of GTPases that control membrane trafficking in eukaryotic cells, and increasing evidence indicates that their functions are tightly coordinated. Because many workers in this field have focused on only one family, this meeting was designed to integrate our understanding of the two families. The conference was organized by Elizabeth Sztul (University of Alabama, Birmingham, USA) and Jim Casanova (University of Virginia, Charlottesville, USA), and provided an opportunity for approximately 90 scientists to communicate their work and discuss future directions for the field. The talks highlighted the structural, functional and regulatory properties of Arf and Rab GTPases and the need to develop coordinated approaches to investigate them. Here, we present the major themes that emerged from the meeting.

Core competencies in teaching and training for doctors in Scotland: a review of the literature and stakeholder survey.

BACKGROUND: The UK General Medical Council requires all registered doctors to be competent in all areas of their work, including teaching and training. AIMS: The current research sought consensus on core competencies for all consultants and GPs involved in teaching and training in Scotland. METHOD: A draft list of 80 competencies was developed from the literature and made available as a survey to all consultants and GPs with teaching roles and all final year speciality trainees working in Scotland. Respondents rated the importance of each competency and provided free text comments. RESULTS: There were 1026 responses. Eighteen competencies were rated as "high priority", and are recommended as a baseline for all doctors involved in teaching and training; 55 were rated as "medium priority", and are recommended in relation to specific teaching and training roles; and 7 were rated as "low priority". Free text responses suggested the topic was controversial and emotive, and emphasised the importance of further work to engage trainers. CONCLUSIONS: The findings appeared to have face validity, and it was felt these could be used as the basis for developing a "Scottish Trainer Framework" for doctors and others involved in teaching and training in Scotland.

Neurophysiology of Resilience in Juvenile Fibromyalgia.

Objective: Juvenile fibromyalgia (JFM) is a chronic pain syndrome predominantly affecting adolescent girls. Resilience may be a protective factor in coping with pain, reducing affective burden, and promoting positive outlooks. Brain regions affected in JFM overlap with those linked to resilience, particularly in the default-mode network (DMN). We investigate the role of resilience on core somatic and affective symptoms in JFM and assess the neurophysiological substrates for the first time. Methods: Forty-one girls with JFM and 40 pain-free adolescents completed a resting-state fMRI assessment and self-report questionnaires. We used clustering analyses to group JFM participants based on resilience, and principal component analyses to summarize core somatic and affective symptoms. We estimated whole-brain and within-DMN connectivity and assessed differences between higher and lower resilience JFM groups and compared their connectivity patterns to pain-free participants. Results: The higher resilience JFM group had less affective (T=4.03; p<.001) but similar core somatic symptoms (T=1.05; p=.302) than the lower resilience JFM group. They had increased whole-brain (T's>3.90, pFDR's<.03) and within-DMN (T=2.20, p=.03) connectivity strength, and higher connectivity between DMN nodes and self-referential, regulatory, and reward-processing regions. Conversely, higher DMN-premotor connectivity was observed in the lower resilience group. Conclusion: JFM participants with higher resilience were protected affectively but not in core somatic symptoms. Greater resilience was accompanied by higher signal integration within the DMN, a network central to internally oriented attention and flexible attention shifting. Crucially, the connectivity pattern in highly resilient patients resembled that of pain-free adolescents, which was not the case for the lower resilience group.