Balancing competing effects of tissue growth and cytoskeletal regulation during Drosophila wing disc development.

How a developing organ robustly coordinates the cellular mechanics and growth to reach a final size and shape remains poorly understood. Through iterations between experiments and model simulations that include a mechanistic description of interkinetic nuclear migration, we show that the local curvature, height, and nuclear positioning of cells in the Drosophila wing imaginal disc are defined by the concurrent patterning of actomyosin contractility, cell-ECM adhesion, ECM stiffness, and interfacial membrane tension. We show that increasing cell proliferation via different growth-promoting pathways results in two distinct phenotypes. Triggering proliferation through insulin signaling increases basal curvature, but an increase in growth through Dpp signaling and Myc causes tissue flattening. These distinct phenotypic outcomes arise from differences in how each growth pathway regulates the cellular cytoskeleton, including contractility and cell-ECM adhesion. The coupled regulation of proliferation and cytoskeletal regulators is a general strategy to meet the multiple context-dependent criteria defining tissue morphogenesis.

Study of Impacts of Two Types of Cellular Aging on the Yeast Bud Morphogenesis.

Understanding the mechanisms of cellular aging processes is crucial for attempting to extend organismal lifespan and for studying age-related degenerative diseases. Yeast cells divide through budding, providing a classical biological model for studying cellular aging. With their powerful genetics, relatively short lifespan and well-established signaling pathways also found in animals, yeast cells offer valuable insights into the aging process. Recent experiments suggested the existence of two aging modes in yeast characterized by nucleolar and mitochondrial declines, respectively. In this study, by analyzing experimental data it was shown that cells evolving into those two aging modes behave differently when they are young. While buds grow linearly in both modes, cells that consistently generate spherical buds throughout their lifespan demonstrate greater efficacy in controlling bud size and growth rate at young ages. A three-dimensional chemical-mechanical model was developed and used to suggest and test hypothesized mechanisms of bud morphogenesis during aging. Experimentally calibrated simulations showed that tubular bud shape in one aging mode could be generated by locally inserting new materials at the bud tip guided by the polarized Cdc42 signal during the early stage of budding. Furthermore, the aspect ratio of the tubular bud could be stabilized during the late stage, as observed in experiments, through a reduction on the new cell surface material insertion or an expansion of the polarization site. Thus model simulations suggest the maintenance of new cell surface material insertion or chemical signal polarization could be weakened due to cellular aging in yeast and other cell types.

Recycling glucocorticoids: therapeutic implications of the 11ß-HSD1 enzyme system.

Endogenous glucocorticoids and commonly used oral glucocorticoids have the property of existing in an inactive and active form in vivo. The inactive form can be converted back to the active form, or 'recycled' in cells and tissues that express the 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) enzyme. This recycling provides an important contribution to the action of glucocorticoids. This review examines the literature relating to the importance of 11ß-HSD1 activity during glucocorticoid treatment, with an emphasis on studies examining bone and joint disease and the ability of glucocorticoids to suppress inflammatory damage in models of arthritis. Animal models with global or selective deletion of 11ß-HSD1 have determined the extent to which this recycling is important in normal physiology and during treatment with oral glucocorticoids. These studies demonstrate that 11ß-HSD1-mediated recycling of inactive glucocorticoids has a substantial action and indeed is responsible for the majority of the effects of orally administered glucocorticoids on a range of tissues. Importantly, the anti-inflammatory actions of glucocorticoids appear largely through this mechanism such that mice that lack 11ß-HSD1 are resistant to the anti-inflammatory actions of glucocorticoids. The recognition that to a large extent the circulating inactive counterpart of these glucocorticoids is more important to anti-inflammatory effects than the active glucocorticoid presents novel opportunities to more selectively target glucocorticoids to tissues or to reduce the likely side effects.

Magnetic Resonance-Guided focused ultrasound surgery for Parkinson's disease: A mini-review and comparison between deep brain stimulation.

Magnetic resonance-guided focused ultrasound (MRgFUS) is a new surgical treatment for Parkinson's disease (PD). Previous experience with radiofrequency lesionectomy and deep brain stimulation (DBS) has identified several candidate targets for MRgFUS intended to alleviate the motor symptoms of PD. The main advantage of MRgFUS is that it is incisionless. MRgFUS has certain limitations and is associated with adverse effects. The present study reviews the literature on conventional surgical interventions for PD, discusses recent studies on MRgFUS, and the comparison between DBS and MRgFUS for PD. The reviews aims to provide an essential reference for neurologists to select the appropriate treatments for patients with PD.

Development of Shortened Enrichment Methods for Detection of Salmonella Typhimurium Spiked in Milk.

Rapid and accurate testing of pathogenic Salmonella enterica in dairy products could reduce the risk of exposure to the bacterial pathogens for consumers. This study aimed to reduce the assessment time needed for enteric bacteria recovery and quantification in food using the natural growth properties of Salmonella enterica Typhimurium (S. Typhimurium) in cow's milk and efficiently using rapid PCR methods. Over 5 h of 37 °C enrichment, culture and PCR methods measured increases in the non-heat-treated S. Typhimurium concentration at similar rates, with an average increase of 2.7 log10 CFU/mL between the start of enrichment and 5 h. In contrast, no bacteria were recovered by culture after S. Typhimurium in milk received heat treatment, and the number of gene copies of heat-treated Salmonella detected by PCR did not increase with the enrichment time. Thus, comparing culture and PCR data over just 5 h of enrichment time can detect and differentiate between replicating bacteria and dead bacteria.

Skin 11ß-hydroxysteroid dehydrogenase type 1 enzyme expression regulates burn wound healing and can be targeted to modify scar characteristics.

Background: Excessive scarring and fibrosis are the most severe and common complications of burn injury. Prolonged exposure to high levels of glucocorticoids detrimentally impacts on skin, leading to skin thinning and impaired wound healing. Skin can generate active glucocorticoids locally through expression and activity of the 11ß-hydroxysteroid dehydrogenase type 1 enzyme (11ß-HSD1). We hypothesised that burn injury would induce 11ß-HSD1 expression and local glucocorticoid metabolism, which would have important impacts on wound healing, fibrosis and scarring. We additionally proposed that pharmacological manipulation of this system could improve aspects of post-burn scarring. Methods: Skin 11ß-HSD1 expression in burns patients and mice was examined. The impacts of 11ß-HSD1 mediating glucocorticoid metabolism on burn wound healing, scar formation and scar elasticity and quality were additionally examined using a murine 11ß-HSD1 genetic knockout model. Slow-release scaffolds containing therapeutic agents, including active and inactive glucocorticoids, were developed and pre-clinically tested in mice with burn injury. Results: We demonstrate that 11ß-HSD1 expression levels increased substantially in both human and mouse skin after burn injury. 11ß-HSD1 knockout mice experienced faster wound healing than wild type mice but the healed wounds manifested significantly more collagen deposition, tensile strength and stiffness, features characteristic of excessive scarring. Application of slow-release prednisone, an inactive glucocorticoid, slowed the initial rate of wound closure but significantly reduced post-burn scarring via reductions in inflammation, myofibroblast generation, collagen production and scar stiffness. Conclusions: Skin 11ß-HSD1 expression is a key regulator of wound healing and scarring after burn injury. Application of an inactive glucocorticoid capable of activation by local 11ß-HSD1 in skin slows the initial rate of wound closure but significantlyimproves scar characteristics post burn injury.

Highly Sensitive, Flow Cytometry-Based Measurement of Intestinal Permeability in Models of Experimental Colitis.

BACKGROUND & AIMS: Increased intestinal permeability is seen in a variety of inflammatory conditions such as enteric infections and inflammatory bowel disease. Because barrier function can provide a key biomarker of disease severity, it often is assayed in animal models. A common methodology involves gavaging mice with fluorescein isothiocyanate-conjugated dextran (FITC-D), followed by cardiac puncture to assay plasma fluorescence on a spectrophotometer. Although the FITC-D method is relatively simple, its sensitivity is limited and enables only a single measurement because the test requires killing the subject. Herein, we describe a novel flow cytometry-based method of intestinal permeability measurement based on detection of orally gavaged ovalbumin (OVA) that leaks out of the gut. Our approach uses minute blood volumes collected from the tail vein, permitting repeated testing of the same subject at multiple time points. By comparing this assay against the gold standard FITC-D method, we show the expanded utility of our OVA assay in measuring intestinal permeability. METHODS: We directly compared our OVA assay against the FITC-D assay by co-administering both probes orally to the same animals and subsequently using their respective methodologies to measure intestinal permeability by detecting probe levels in the plasma. Permeability was assessed in mice genetically deficient in intestinal mucus production or glycosylation. In addition, wild-type mice undergoing dextran sodium sulfate-induced colitis or infected by the enteric bacterial pathogen Citrobacter rodentium also were tested. RESULTS: The OVA assay showed very high efficacy in all animal models of intestinal barrier dysfunction tested. Besides identifying intestinal barrier dysfunction in mice with impaired mucin glycosylation, the assay also allowed for repeated tracking of intestinal permeability within the same animal over time, providing data that cannot be easily acquired with other currently applied methods. CONCLUSIONS: The OVA assay is a highly sensitive and effective method of measuring intestinal permeability in mouse models of barrier dysfunction and experimental colitis.

Role of wound microbiome, strategies of microbiota delivery system and clinical management.

Delayed wound healing is one of the most global public health threats affecting nearly 100 million people each year, particularly the chronic wounds. Many confounding factors such as aging, diabetic disease, medication, peripheral neuropathy, immunocompromises or arterial and venous insufficiency hyperglycaemia are considered to inhibit wound healing. Therapeutic approaches for slow wound healing include anti-infection, debridement and the use of various wound dressings. However, the current clinical outcomes are still unsatisfied. In this review, we discuss the role of skin and wound commensal microbiota in the different healing stages, including inflammation, cell proliferation, re-epithelialization and remodelling phase, followed by multiple immune cell responses to commensal microbiota. Current clinical management in treating surgical wounds and chronic wounds was also reviewed together with potential controlled delivery systems which may be utilized in the future for the topical administration of probiotics and microbiomes. This review aims to introduce advances, novel strategies, and pioneer ideas in regulating the wound microbiome and the design of controlled delivery systems.

Electrographic lead I and V5 monitoring could have detected a missed left-side pneumothorax intraoperatively.

We present an EKG monitoring strategy to detect pneumothorax during high-risk surgery. In the literature, EKG changes and pneumothorax are well-described. However, anesthesiologists only monitor lead II on a three-lead EKG system in the operating room. In our case, there was only a subtle change in lead II for a left-sided pneumothorax, which could have been easily missed. On the contrary, there was a marked QRS amplitude reduction and T wave flattening/inversion in lead I and V5 . We recommend lead V5 be added to the continuous monitoring and lead I be periodically checked for surgeries known to potentially cause pneumothorax.

Trauma Anesthesiology Perioperative Management Update.

Anesthesia for patients with life-threatening injuries is an essential part of post-accident care. Unfortunately, there is variability in trauma anesthesia care and numerous nonstandardized methods of working with patients remain. Uncertainty exists as to when and how best to intubate trauma patients, the use of vasopressors, and the appropriate management of severe traumatic brain injury. Some physicians recommend prehospital rapid sequence intubation, whereas others use bag-mask ventilation at lower pressures with no cricoid pressure and early transport to a trauma center. Overall, the absence of uniformity in trauma anesthesia care underlines the need for continued study and dialogue to define best practices and optimize patient outcomes.

Human JAK1 gain of function causes dysregulated myelopoeisis and severe allergic inflammation.

Primary atopic disorders are a group of inborn errors of immunity that skew the immune system toward severe allergic disease. Defining the biology underlying these extreme monogenic phenotypes reveals shared mechanisms underlying common polygenic allergic disease and identifies potential drug targets. Germline gain-of-function (GOF) variants in JAK1 are a cause of severe atopy and eosinophilia. Modeling the JAK1GOF (p.A634D) variant in both zebrafish and human induced pluripotent stem cells (iPSCs) revealed enhanced myelopoiesis. RNA-Seq of JAK1GOF human whole blood, iPSCs, and transgenic zebrafish revealed a shared core set of dysregulated genes involved in IL-4, IL-13, and IFN signaling. Immunophenotypic and transcriptomic analysis of patients carrying a JAK1GOF variant revealed marked Th cell skewing. Moreover, long-term ruxolitinib treatment of 2 children carrying the JAK1GOF (p.A634D) variant remarkably improved their growth, eosinophilia, and clinical features of allergic inflammation. This work highlights the role of JAK1 signaling in atopic immune dysregulation and the clinical impact of JAK1/2 inhibition in treating eosinophilic and allergic disease.

Environmental and behavioural exposure pathways associated with diarrhoea and enteric pathogen detection in 5-month-old, periurban Kenyan infants: a cross-sectional study.

OBJECTIVES: The aim of this study was to test whether household environmental hygiene and behavioural conditions moderated associations between diarrhoea and enteric pathogen detection in infants 5 months of age in Kenya and pathogen sources, including latrine access, domestic animal co-habitation and public food sources. DESIGN: Cross-sectional study utilising enrolment survey data of households participating in the Safe Start cluster-randomised controlled trial . SETTING: Kisumu, Kenya. PARTICIPANTS: A total of 898 caregivers with 5-month (22 week ± 1 week) aged infants were enrolled in the study and completed the enrolment survey. PRIMARY AND SECONDARY OUTCOME MEASURES: Outcomes were (1) caregiver-reported 7-day diarrhoea prevalence and (2) count of types of enteric viruses, bacteria and parasites in infant stool. Exposures and effect modifiers included water access and treatment, cohabitation with domestic animals, sanitation access, handwashing practices, supplemental feeding, access to refrigeration and flooring. RESULTS: Reported handwashing after handling animals (adjusted odds ratio (aOR)=0.20; 95% CI=0.06 to 0.50) and before eating (aOR=0.44; 95% CI=0.26 to 0.73) were strongly associated with lower risk of caregiver-reported diarrhoea, while cohabitation with animals (aOR=1.54; 95% CI=1.01 to 2.34) living in a household with vinyl-covered dirt floors (aOR=0.60; 95% CI=0.45 to 0.87) were strongly associated with pathogen codetection in infants. Caregiver handwashing after child (p=0.02) or self-defecation (p=0.03) moderated the relationship between shared sanitation access and infant exposure to pathogens, specifically private latrine access was protective against pathogen exposure of infants in households, where caregivers washed hands after defecation. In the absence of handwashing, access to private sanitation posed no benefits over shared latrines for protecting infants from exposure. CONCLUSION: Our evidence highlights eliminating animal cohabitation and improving flooring, postdefecation and food-related handwashing, and safety and use of cow milk sources as interventions to prevent enteric pathogen exposure of young infants in Kenya. TRIAL REGISTRATION NUMBER: NCT03468114.

Thermoresponsive and Injectable Hydrogel for Tissue Agnostic Regeneration.

Injectable hydrogels can support the body's innate healing capability by providing a temporary matrix for host cell ingrowth and neovascularization. The clinical adoption of current injectable systems remains low due to their cumbersome preparation requirements, device malfunction, product dislodgment during administration, and uncontrolled biological responses at the treatment site. To address these challenges, a fully synthetic and ready-to-use injectable biomaterial is engineered that forms an adhesive hydrogel that remains at the administration site regardless of defect anatomy. The product elicits a negligible local inflammatory response and fully resorbs into nontoxic components with minimal impact on internal organs. Preclinical animal studies confirm that the engineered hydrogel upregulates the regeneration of both soft and hard tissues by providing a temporary matrix to support host cell ingrowth and neovascularization. In a pilot clinical trial, the engineered hydrogel is successfully administered to a socket site post tooth extraction and forms adhesive hydrogel that stabilizes blood clot and supports soft and hard tissue regeneration. Accordingly, this injectable hydrogel exhibits high therapeutic potential and can be adopted to address multiple unmet needs in different clinical settings.

Controlled dual release of dihydrotestosterone and flutamide from polycaprolactone electrospun scaffolds accelerate burn wound healing.

Wound healing is a complex process involving multiple independent and overlapping sequential physiological mechanisms. In addition to cutaneous injury, a severe burn stimulates physiological derangements that induce a systemic hypermetabolic response resulting in impaired wound healing. Topical application of the anti-androgen drug, flutamide accelerates cutaneous wound healing, whereas paradoxically systemic dihydrotestosterone (DHT) improves burn wound healing. We developed and characterized a PCL scaffold that is capable of controlled release of androgen (DHT) and anti-androgen (F) individually or together. This study aims to investigate whether local modification of androgen actions has an impact on burn injury wound healing. In a full-thickness burn wound healing, mouse model, DHT/F-scaffold showed a significantly faster wound healing compared with F-scaffold or DHT-scaffold. Histology analysis confirmed that DHT/F-scaffold exhibited higher re-epithelization, cell proliferation, angiogenesis, and collagen deposition. Dual release of DHT and F from PCL scaffolds promoted cell proliferation of human keratinocytes and alters the keratinocyte cell cycle. Lastly, no adverse effects on androgen-dependent organs, spleen and liver were observed. In conclusion, we demonstrated DHT plus F load PCL scaffolds accelerated burn wound healing when loading alone did not. These findings point to a complex role of androgens in burn wound healing and open novel therapeutic avenues for treating severe burn patients.

Focused Ultrasound Thalamotomy for the Treatment of Essential Tremor: A 2-Year Outcome Study of Chinese People.

Background: Essential tremor (ET) is a common movement disorder among elderly individuals worldwide and is occasionally associated with a high risk for mild cognitive impairment and dementia. This retrospective study aimed to determine the clinical outcome of unilateral magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy in Chinese patients with ET. Methods: In total, 31 male and 17 female patients with drug-refractory ET were enrolled in this research study from January 2017 to September 2019. The severity of tremor and disability were assessed using the Clinical Rating Scale for Tremor (CRST) within a 2-year follow-up period. Results: The mean age of the participants was 59.14 ± 13.5 years. The mean skull density ratio (SDR) was 0.5 ± 0.1. The mean highest temperature was 57.0 ± 2.4°C. The mean number of sonications was 10.0 ± 2.6. The average maximum energy was 19,710.5 ± 8,624.9 J. The total CRST scores and sub-scores after MRgFUS thalamotomy significantly reduced during each follow-up (p < 0.001). All but four (8.3%) of the patients had reversible adverse events (AEs) after the procedure. Conclusions: MRgFUS had sustained clinical efficacy 2 years after treatment for intractable ET. Only few patients presented with thalamotomy-related AEs including numbness, weakness, and ataxia for an extended period. Most Chinese patients were treated safely and effectively despite their low SDR.

Mapping of pseudouridine residues on cellular and viral transcripts using a novel antibody-based technique.

Pseudouridine (Ψ) is the most common noncanonical ribonucleoside present on mammalian noncoding RNAs (ncRNAs), including rRNAs, tRNAs, and snRNAs, where it contributes ∼7% of the total uridine level. However, Ψ constitutes only ∼0.1% of the uridines present on mRNAs and its effect on mRNA function remains unclear. Ψ residues have been shown to inhibit the detection of exogenous RNA transcripts by host innate immune factors, thus raising the possibility that viruses might have subverted the addition of Ψ residues to mRNAs by host pseudouridine synthase (PUS) enzymes as a way to inhibit antiviral responses in infected cells. Here, we describe and validate a novel antibody-based Ψ mapping technique called photo-crosslinking-assisted Ψ sequencing (PA-Ψ-seq) and use it to map Ψ residues on not only multiple cellular RNAs but also on the mRNAs and genomic RNA encoded by HIV-1. We describe 293T-derived cell lines in which human PUS enzymes previously reported to add Ψ residues to human mRNAs, specifically PUS1, PUS7, and TRUB1/PUS4, were inactivated by gene editing. Surprisingly, while this allowed us to assign several sites of Ψ addition on cellular mRNAs to each of these three PUS enzymes, Ψ sites present on HIV-1 transcripts remained unaffected. Moreover, loss of PUS1, PUS7, or TRUB1 function did not significantly reduce the level of Ψ residues detected on total human mRNA below the ∼0.1% level seen in wild-type cells, thus implying that the PUS enzyme(s) that adds the bulk of Ψ residues to human mRNAs remains to be defined.

Low-protein diet accelerates wound healing in mice post-acute injury.

BACKGROUND: Wound healing processes are influenced by macronutrient intake (protein, carbohydrate and fat). The most favourable diet for cutaneous wound healing is not known, although high-protein diets are currently favoured clinically. This experimental study investigates the optimal macronutrient balance for cutaneous wound healing using a mouse model and the Geometric Framework, a nutrient modelling method, capable of analyzing the individual and interactive effects of a wide spectrum of macronutrient intake. METHODS: Two adjacent and identical full-thickness skin excisions (1 cm2) were surgically created on the dorsal area of male C57BL/6 mice. Mice were then allocated to one of 12 high-energy diets that varied in protein, carbohydrate and fat content. In select diets, wound healing processes, cytokine expression, energy expenditure, body composition, muscle and fat reserves were assessed. RESULTS: Using the Geometric Framework, we show that a low-protein intake, coupled with a balanced intake of carbohydrate and fat is optimal for wound healing. Mice fed a low-protein diet progressed quickly through wound healing stages with favourable wound inflammatory cytokine expression and significantly accelerated collagen production. These local processes were associated with an increased early systemic inflammatory response and a higher overall energy expenditure, related to metabolic changes occurring in key macronutrient reserves in lean body mass and fat depots. CONCLUSIONS: The results suggest that a low-protein diet may have a greater potential to accelerate wound healing than the current clinically used high-protein diets.

Prebiotic Enriched Exclusive Enteral Nutrition Suppresses Colitis via Gut Microbiome Modulation and Expansion of Anti-inflammatory T Cells in a Mouse Model of Colitis.

BACKGROUND & AIMS: Exclusive enteral nutrition (EEN) is used to treat pediatric Crohn's disease (CD), but therapeutic benefits are variable, and EEN can lead to microbial dysbiosis. Because of reported lower efficacy EEN is not routinely used to treat pediatric ulcerative colitis (UC). Inulin-type fructans (IN) beneficially modulate the gut microbiome and promote expansion of anti-inflammatory immune cells. We hypothesized that enriching EEN with IN (EEN IN) would enhance treatment efficacy. To test this, we examined the effects of EEN IN on colitis development, the gut microbiome, and CD4+ T cells using an adoptive T-cell transfer model of colitis. METHODS: TCR-ß deficient (-/-) mice were randomized to 1 of 4 groups: (1) Control, (2) Chow, (3) EEN, and (4) EEN IN, and naive CD4+ T cells were adoptively transferred into groups 2-4, after which mice were monitored for 5 weeks before experimental endpoint. RESULTS: Mice fed EEN IN showed greater colitis protection, with colonic shortening, goblet cell, and crypt density loss reduced compared with EEN fed mice and reduced disease activity and immune cell infiltration compared with chow fed mice, and less crypt hyperplasia and higher survival compared with both groups. EEN IN mice had less deterioration in the colonic mucus layer and had increased levels of Foxp3+IL-10+ and Rorγt+IL-22+ and reduced levels of Tbet+IFNγ+ and Tbet+TNF+ CD4+ T cells. EEN IN also led to higher butyrate concentrations, Bifidobacterium spp. and Anaerostipes caccae relative abundance, and lower [Clostridium] innocuum group spp. and Escherichia-Shigella spp. relative abundance. CONCLUSIONS: The EEN IN group showed reduced colitis development as compared with the chow and EEN groups. This highlights the potential benefits of EEN IN as a novel induction therapy for pediatric CD and UC patients.

Mapping RNA Modifications Using Photo-Crosslinking-Assisted Modification Sequencing.

Epitranscriptomic RNA modifications function as an important layer of gene regulation that modulates the function of RNA transcripts. A key step in understanding how RNA modifications regulate biological processes is the mapping of their locations, which is most commonly done by RNA immunoprecipitation (RIP) using modification-specific antibodies. Here, we describe the use of a photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation (PAR-CLIP) method, in conjunction with RNA modification-specific antibodies, to map modification sites. First described as photo-crosslinking-assisted m6A sequencing (PA-m6A-seq), this method allows the mapping of RNA modifications at a higher resolution, with lower background than traditional RIP, and can be adapted to any RNA modification for which a specific antibody is available.

Epitranscriptomic addition of m6A regulates HIV-1 RNA stability and alternative splicing.

Previous work has demonstrated that the epitranscriptomic addition of m6A to viral transcripts can promote the replication and pathogenicity of a wide range of DNA and RNA viruses, including HIV-1, yet the underlying mechanisms responsible for this effect have remained unclear. It is known that m6A function is largely mediated by cellular m6A binding proteins or readers, yet how these regulate viral gene expression in general, and HIV-1 gene expression in particular, has been controversial. Here, we confirm that m6A addition indeed regulates HIV-1 RNA expression and demonstrate that this effect is largely mediated by the nuclear m6A reader YTHDC1 and the cytoplasmic m6A reader YTHDF2. Both YTHDC1 and YTHDF2 bind to multiple distinct and overlapping sites on the HIV-1 RNA genome, with YTHDC1 recruitment serving to regulate the alternative splicing of HIV-1 RNAs. Unexpectedly, while YTHDF2 binding to m6A residues present on cellular mRNAs resulted in their destabilization as previously reported, YTHDF2 binding to m6A sites on HIV-1 transcripts resulted in a marked increase in the stability of these viral RNAs. Thus, YTHDF2 binding can exert diametrically opposite effects on RNA stability, depending on RNA sequence context.