Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 330
Filter
1.
J Econ Entomol ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38984892

ABSTRACT

Aprostocetus hagenowii (Ratzeburg) is a parasitoid wasp that parasitizes the oothecae of peridomestic pest cockroaches. A. hagenowii has been used in integrated pest management (IPM) programs for cockroach control but little is known about how this parasitoid responds to the insecticides commonly used for cockroach management. Five insecticidal gel bait products containing indoxacarb, clothianidin, fipronil, dinotefuran, or abamectin B1 were tested for their toxicity towards A. hagenowii and the American cockroach, Periplaneta americana (L.; Blattodea: Blattidae), a host of A. hagenowii and a common pest. All baits were tested as fresh and 1-d aged deposits. Indoxacarb was the only active ingredient that did not cause significant (P < 0.05) A. hagenowii mortality compared to the control in both the fresh and aged gel experiments (Median survival time [MST]s: 168 h fresh, 72 h aged). Clothianidin caused the lowest A. hagenowii MSTs across experiments (24 h, fresh and aged). All baits caused significant P. americana mortality as fresh and 1-d aged deposits (P < 0.05). Indoxacarb appears most compatible with A. hagenowii in cockroach IPM.

3.
Front Plant Sci ; 15: 1344022, 2024.
Article in English | MEDLINE | ID: mdl-38510438

ABSTRACT

Corn (Zea mays) biomass accumulation and nutrient uptake by the six-leaf collar (V6) growth stage are low, and therefore, synchronizing nutrient supply with crop demand could potentially minimize nutrient loss and improve nutrient use efficiency. Knowledge of corn's response to nutrient stress in the early growth stages could inform such nutrient management. Field studies were conducted to assess corn recovery from when no fertilizer application is made until the V6 growth stage, and thereafter, applying fertilizer rates as those in non-stressed conditions. The early season nutrient stress and non-stress conditions received the same amount of nutrients. As the availability of nutrients for plant uptake is largely dependent on soil moisture, corn recovery from the early season nutrient stress was assessed under different soil moisture regimes induced via irrigation scheduling at 50% and 80% field capacity under overhead and subsurface drip irrigation (SSDI) systems. Peanut (Arachis hypogaea) was the previous crop under all conditions, and the fields were under cereal rye (Secale cereale) cover crop prior to planting corn. At the V6 growth stage, the nutrient concentrations of the early season-stressed crops, except for copper, were above the minimum threshold of sufficiency ranges reported for corn. However, the crops showed poor growth, with biomass accumulation being reduced by over 50% compared to non-stressed crops. Also, the uptake of all nutrients was significantly lower under the early season nutrient stress conditions. The recovery of corn from the early season nutrient stress was low. Compared to non-stress conditions, the early season nutrient stress caused 1.58 Mg ha-1 to 3.4 Mg ha-1 yield reduction. The percent yield reduction under the SSDI system was 37.6-38.2% and that under the overhead irrigation system was 11.7-13%. The high yield reduction from the early season nutrient stress under the SSDI system was because of water stress conditions in the topsoil soil layer. The findings of the study suggest ample nutrient supply in the early season growth stage is critical for corn production, and thus, further studies are recommended to determine the optimum nutrient supply for corn at the initial growth stages.

4.
bioRxiv ; 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38464173

ABSTRACT

Cell cycle progression is governed by complexes of the cyclin-dependent kinases (CDKs) and their regulatory subunits cyclin and Cks1. CDKs phosphorylate hundreds of substrates, often at multiple sites. Multisite phosphorylation depends on Cks1, which binds initial priming phosphorylation sites to promote secondary phosphorylation at other sites. Here, we describe a similar role for a recently discovered phosphate-binding pocket (PP) on B-type cyclins. Mutation of the PP in Clb2, the major mitotic cyclin of budding yeast, alters bud morphology and delays the onset of anaphase. Using phosphoproteomics in vivo and kinase reactions in vitro, we find that mutation of the PP reduces phosphorylation of several CDK substrates, including the Bud6 subunit of the polarisome and the Cdc16 and Cdc27 subunits of the anaphase-promoting complex/cyclosome. We conclude that the cyclin PP, like Cks1, controls the timing of multisite phosphorylation on CDK substrates, thereby helping to establish the robust timing of cell-cycle events.

6.
Int J Lab Hematol ; 46(3): 495-502, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38379463

ABSTRACT

BACKGROUND: Detection of del(17p) in myeloma is generally performed by fluorescence in situ hybridization (FISH) on a slide with analysis of up to 200 nuclei. The small cell sample analyzed makes this a low precision test. We report the utility of an automated FISH method, called "immuno-flowFISH", to detect plasma cells with adverse prognostic risk del(17p) in bone marrow and blood samples of patients with myeloma. METHODS: Bone marrow (n = 31) and blood (n = 19) samples from 35 patients with myeloma were analyzed using immuno-flowFISH. Plasma cells were identified by CD38/CD138-immunophenotypic gating and assessed for the 17p locus and centromere of chromosome 17. Cells were acquired on an AMNIS ImageStreamX MkII imaging flow cytometer using INSPIRE software. RESULTS: Chromosome 17 abnormalities were identified in CD38/CD138-positive cells in bone marrow (6/31) and blood (4/19) samples when the percent plasma cell burden ranged from 0.03% to 100% of cells. Abnormalities could be identified in 14.5%-100% of plasma cells. CONCLUSIONS: The "immuno-flowFISH" imaging flow cytometric method could detect del(17p) in plasma cells in both bone marrow and blood samples of myeloma patients. This method was also able to detect gains and losses of chromosome 17, which are also of prognostic significance. The lowest levels of 0.009% (bone marrow) and 0.001% (blood) for chromosome 17 abnormalities was below the detection limit of current FISH method. This method offers potential as a new means of identifying these prognostically important chromosomal defects, even when only rare cells are present and for serial disease monitoring.


Subject(s)
Chromosomes, Human, Pair 17 , Flow Cytometry , In Situ Hybridization, Fluorescence , Multiple Myeloma , Plasma Cells , Humans , Multiple Myeloma/diagnosis , Multiple Myeloma/genetics , Multiple Myeloma/blood , Multiple Myeloma/pathology , Plasma Cells/pathology , Flow Cytometry/methods , Chromosomes, Human, Pair 17/genetics , Male , Female , Aged , Middle Aged , Bone Marrow/pathology , Chromosome Deletion , Aged, 80 and over , Immunophenotyping , Adult
7.
Syst Rev ; 13(1): 21, 2024 01 06.
Article in English | MEDLINE | ID: mdl-38184622

ABSTRACT

BACKGROUND: Critical bleeding events in adults and children with ITP are medical emergencies; however, evidence-based treatment protocols are lacking. Due to the severe thrombocytopenia, (typically platelet count less than 20 × 109/L), a critical bleed portends a high risk of death or disability. We plan to perform a systematic review and meta-analysis of treatments for critical bleeding in patients with ITP that will inform evidence-based recommendations. METHODS: Literature searches will be conducted in four electronic databases: Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed. Eligible studies will be randomized controlled trials or observational studies that enrolled patients with ITP describing one or more interventions for the management of critical bleeding. Title and abstract screening, full-text screening, data extraction, and risk of bias evaluation will be conducted independently and in duplicate using Covidence and Excel. Outcomes will be pooled for meta-analysis where appropriate or summarized descriptively. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology will be used to evaluate the certainty of the evidence. Primary outcomes of interest will include frequency of critical bleeds, mortality and bleeding-related mortality, bleeding resolution, platelet count, and disability. DISCUSSION: Evidence-based treatments for critical bleeding in patients with ITP are needed to improve patient outcomes and standardize care in the emergency setting. SYSTEMATIC REVIEW REGISTRATION: CRD42020161206.


Subject(s)
Hemorrhage , Purpura, Thrombocytopenic, Idiopathic , Adult , Child , Humans , Hemorrhage/therapy , Meta-Analysis as Topic , Purpura, Thrombocytopenic, Idiopathic/complications , Purpura, Thrombocytopenic, Idiopathic/therapy , Systematic Reviews as Topic , Thrombocytopenia/complications , Thrombocytopenia/therapy
8.
J Cheminform ; 16(1): 5, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38212855

ABSTRACT

Probing the surface of proteins to predict the binding site and binding affinity for a given small molecule is a critical but challenging task in drug discovery. Blind docking addresses this issue by performing docking on binding regions randomly sampled from the entire protein surface. However, compared with local docking, blind docking is less accurate and reliable because the docking space is too largetly sampled. Cavity detection-guided blind docking methods improved the accuracy by using cavity detection (also known as binding site detection) tools to guide the docking procedure. However, it is worth noting that the performance of these methods heavily relies on the quality of the cavity detection tool. This constraint, namely the dependence on a single cavity detection tool, significantly impacts the overall performance of cavity detection-guided methods. To overcome this limitation, we proposed Consensus Blind Dock (CoBDock), a novel blind, parallel docking method that uses machine learning algorithms to integrate docking and cavity detection results to improve not only binding site identification but also pose prediction accuracy. Our experiments on several datasets, including PDBBind 2020, ADS, MTi, DUD-E, and CASF-2016, showed that CoBDock has better binding site and binding mode performance than other state-of-the-art cavity detector tools and blind docking methods.

9.
Front Plant Sci ; 14: 1248152, 2023.
Article in English | MEDLINE | ID: mdl-37794937

ABSTRACT

Lint yield in cotton is governed by light intercepted by the canopy (IPAR), radiation use efficiency (RUE), and harvest index (HI). However, the conventional methods of measuring these yield-governing physiological parameters are labor-intensive, time-consuming and requires destructive sampling. This study aimed to explore the use of low-cost and high-resolution UAV-based RGB and multispectral imagery 1) to estimate fraction of IPAR (IPARf), RUE, and biomass throughout the season, 2) to estimate lint yield using the cotton fiber index (CFI), and 3) to determine the potential use of biomass and lint yield models for estimating cotton HI. An experiment was conducted during the 2021 and 2022 growing seasons in Tifton, Georgia, USA in randomized complete block design with five different nitrogen treatments. Different nitrogen treatments were applied to generate substantial variability in canopy development and yield. UAV imagery was collected bi-weekly along with light interception and biomass measurements throughout the season, and 20 different vegetation indices (VIs) were computed from the imagery. Generalized linear regression was performed to develop models using VIs and growing degree days (GDDs). The IPARf models had R2 values ranging from 0.66 to 0.90, and models based on RVI and RECI explained the highest variation (93%) in IPARf during cross-validation. Similarly, cotton above-ground biomass was best estimated by models from MSAVI and OSAVI. Estimation of RUE using actual biomass measurement and RVI-based IPARf model was able to explain 84% of variation in RUE. CFI from UAV-based RGB imagery had strong relationship (R2 = 0.69) with machine harvested lint yield. The estimated HI from CFI-based lint yield and MSAVI-based biomass models was able to explain 40 to 49% of variation in measured HI for the 2022 growing season. The models developed to estimate the yield-contributing physiological parameters in cotton showed low to strong performance, with IPARf and above-ground biomass having greater prediction accuracy. Future studies on accurate estimation of lint yield is suggested for precise cotton HI prediction. This study is the first attempt of its kind and the results can be used to expand and improve research on predicting functional yield drivers of cotton.

10.
Proc Natl Acad Sci U S A ; 120(43): e2303794120, 2023 10 24.
Article in English | MEDLINE | ID: mdl-37844230

ABSTRACT

ß-arrestins are multivalent adaptor proteins that bind active phosphorylated G protein-coupled receptors (GPCRs) to inhibit G protein signaling, mediate receptor internalization, and initiate alternative signaling events. ß-arrestins link agonist-stimulated GPCRs to downstream signaling partners, such as the c-Raf-MEK1-ERK1/2 cascade leading to ERK1/2 activation. ß-arrestins have been thought to transduce signals solely via passive scaffolding by facilitating the assembly of multiprotein signaling complexes. Recently, however, ß-arrestin 1 and 2 were shown to activate two downstream signaling effectors, c-Src and c-Raf, allosterically. Over the last two decades, ERK1/2 have been the most intensely studied signaling proteins scaffolded by ß-arrestins. Here, we demonstrate that ß-arrestins play an active role in allosterically modulating ERK kinase activity in vitro and within intact cells. Specifically, we show that ß-arrestins and their GPCR-mediated active states allosterically enhance ERK2 autophosphorylation and phosphorylation of a downstream ERK2 substrate, and we elucidate the mechanism by which ß-arrestins do so. Furthermore, we find that allosteric stimulation of dually phosphorylated ERK2 by active-state ß-arrestin 2 is more robust than by active-state ß-arrestin 1, highlighting differential capacities of ß-arrestin isoforms to regulate effector signaling pathways downstream of GPCRs. In summary, our study provides strong evidence for a new paradigm in which ß-arrestins function as active "catalytic" scaffolds to allosterically unlock the enzymatic activity of signaling components downstream of GPCR activation.


Subject(s)
Arrestins , Signal Transduction , beta-Arrestins/metabolism , beta-Arrestin 1/genetics , beta-Arrestin 1/metabolism , Arrestins/metabolism , Allosteric Regulation , Signal Transduction/physiology , Receptors, G-Protein-Coupled/metabolism , Phosphorylation , beta-Arrestin 2/metabolism
11.
Materials (Basel) ; 16(20)2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37895653

ABSTRACT

As the energy demand is expected to double over the next 30 years, there has been a major initiative towards advancing the technology of both energy harvesting and storage for renewable energy. In this work, we explore a subset class of dielectrics for energy storage since ferroelectrics offer a unique combination of characteristics needed for energy storage devices. We investigate ferroelectric lead-free 0.5[Ba(Ti0.8Zr0.2)O3]-0.5(Ba0.7Ca0.3)TiO3 epitaxial thin films with different crystallographic orientations grown by pulsed laser deposition. We focus our attention on the influence of the crystallographic orientation on the microstructure, ferroelectric, and dielectric properties. Our results indicate an enhancement of the polarization and strong anisotropy in the dielectric response for the (001)-oriented film. The enhanced ferroelectric, energy storage, and dielectric properties of the (001)-oriented film is explained by the coexistence of orthorhombic-tetragonal phase, where the disordered local structure is in its free energy minimum.

12.
Insects ; 14(9)2023 Sep 09.
Article in English | MEDLINE | ID: mdl-37754723

ABSTRACT

Parasitoids forage for hosts in dynamic ecosystems and generally have a short period of time to access hosts. The current study examined the optimal reproductive attributes of two egg parasitoids, Paratelenomus saccharalis Dodd (Hymenoptera: Platygastridae) and Ooencyrtus nezarae Ishii (Hymenoptera: Encyrtidae), of the kudzu bug, Megacopta cribraria Fabricius (Hemiptera: Plataspidae). The proportion of O. nezarae and P. saccharalis adult offspring that emerged from M. cribraria eggs and the sex ratio of the parasitoid offspring were compared among treatments for the effects of different adult parasitoid food sources, host egg-to-adult parasitoid ratios, and host exposure times. Our results suggest that honey solution as a food source, a 21:7 host-to-parasitoid ratio, and three-to-five days of exposure time optimized the production of female O. nezarae offspring. For P. saccharalis, honey solution as a food source, a 21:7 host-to-parasitoid ratio, and one day were optimal for maximizing female offspring production. These findings provide new information about the biology of these egg parasitoids.

13.
Eur Urol Open Sci ; 54: 33-42, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37545848

ABSTRACT

Background: The surgical difficulty of partial nephrectomy (PN) varies depending on the operative approach. Existing nephrometry classifications for assessment of surgical difficulty are not specific to the robotic approach. Objective: To develop an international robotic-specific classification of renal masses for preoperative assessment of surgical difficulty of robotic PN. Design setting and participants: The RPN classification (Radius, Position of tumour, iNvasion of renal sinus) considers three parameters: tumour size, tumour position, and invasion of the renal sinus. In an international survey, 45 experienced robotic surgeons independently reviewed de-identified computed tomography images of 144 patients with renal tumours to assess surgical difficulty of robot-assisted PN using a 10-point Likert scale. A separate data set of 248 patients was used for external validation. Outcome measurements and statistical analysis: Multiple linear regression was conducted and a risk score was developed after rounding the regression coefficients. The RPN classification was correlated with the surgical difficulty score derived from the international survey. External validation was performed using a retrospective cohort of 248 patients. RPN classification was also compared with the RENAL (Radius; Exophytic/endophytic; Nearness; Anterior/posterior; Location), PADUA (Preoperative Aspects and Dimensions Used for Anatomic), and SPARE (Simplified PADUA REnal) scoring systems. Results and limitation: The median tumour size was 38 mm (interquartile range 27-49). The majority (81%) of renal tumours were peripheral, followed by hilar (12%) and central (7.6%) locations. Noninvasive and semi-invasive tumours accounted for 37% each, and 26% of the tumours were invasive. The mean surgical difficulty score was 5.2 (standard deviation 1.9). Linear regression analysis indicated that the RPN classification correlated very well with the surgical difficulty score (R2 = 0.80). The R2 values for the other scoring systems were: 0.66 for RENAL, 0.75 for PADUA, and 0.70 for SPARE. In an external validation cohort, the performance of all four classification systems in predicting perioperative outcomes was similar, with low R2 values. Conclusions: The proposed RPN classification is the first nephrometry system to assess the surgical difficulty of renal masses for which robot-assisted PN is planned, and is a useful tool to assist in surgical planning, training and data reporting. Patient summary: We describe a simple classification system to help urologists in preoperative assessment of the difficulty of robotic surgery for partial kidney removal for kidney tumours.

14.
Int J Lab Hematol ; 45(4): 425-435, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37337970

ABSTRACT

Chimeric antigen receptor (CAR) T-cell therapy is a novel adoptive T-cell immunotherapy for haematological malignancies. First introduced into clinical practice in 2017, CAR T-cell therapy is now finding its place in the management of lymphoid malignancies, primarily of B-cell lineage, including lymphoblastic leukaemia, non-Hodgkin lymphoma and plasma cell myeloma, with remarkable therapeutic outcomes. CAR T-cells are a customised therapeutic product for each patient. Manufacture commences with collection of autologous T-cells, which are then genetically engineered ex vivo to express transmembrane CARs. These chimeric proteins consist of an antibody-like extracellular antigen-binding domain, to recognise specific antigens on the surface of tumour cells (e.g. CD19), linked to the intracellular co-stimulatory signalling domains of a T-cell receptor (e.g. CD137). The latter is required for in vivo CAR T-cell proliferation, survival, and durable efficacy. Following reinfusion, CAR T-cells harness the cytotoxic capacity of a patient's immune system. They overcome major mechanisms of tumour immuno-evasion and have potential to generate robust cytotoxic anti-tumour responses. This review discusses the background to CAR T-cell therapies, including their molecular design, mechanisms of action, methods of production, clinical applications and established and emerging technologies for CAR T-cell evaluation. It highlights the need for standardisation, quality control and monitoring of CAR T-cell therapies, to ensure their safety and efficacy in clinical management.


Subject(s)
Antineoplastic Agents , Multiple Myeloma , Receptors, Chimeric Antigen , Humans , Receptors, Chimeric Antigen/genetics , Receptors, Antigen, T-Cell/genetics , T-Lymphocytes , Multiple Myeloma/therapy , Quality Control
15.
J Econ Entomol ; 116(4): 1128-1136, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37227849

ABSTRACT

The Turkestan cockroach, Blatta lateralis (Walker), is a peridomestic pest of growing concern in the US Southwest. The parasitoid Aprostocetus hagenowii (Ratzburg) is used in IPM programs targeting other blattid cockroach species and may aid in B. lateralis suppression. Information about the ability of A. hagenowii to parasitize B. lateralis is lacking. A no-choice host-switching experiment was used to test A. hagenowii acceptance of B. lateralis oothecae, and a multigenerational no-choice experiment was used to determine the suitability of B. lateralis as a host for A. hagenowii over several months of rearing. Periplaneta americana (L.) (Blattodea: Blattidae), the preferred host of A. hagenowii, and Blatta orientalis L., a known host and relative of B. lateralis, were used for comparison. Development time was similar among hosts and generations (P > 0.05). Parasitism success and proportion of female progeny declined significantly with subsequent generations on both Blatta spp. (parasitism success: χ2 = 14.916; df = 2; P = 0.001; proportion female: H = 6.364; df = 2; P = 0.041). These results suggest that A. hagenowii may initially aid in suppression of B. lateralis, but an overall decline in fitness will require repeated releases or provisioning of P. americana oothecae. Development of a strain more suitable for B. lateralis control may be possible via selection from laboratory strains or through use of wild A. hagenowii from areas where B. lateralis is present.


Subject(s)
Cockroaches , Coleoptera , Hymenoptera , Periplaneta , Female , Animals , Biological Control Agents
17.
Methods Mol Biol ; 2635: 149-171, 2023.
Article in English | MEDLINE | ID: mdl-37074662

ABSTRACT

Imaging flow cytometry has the capacity to bridge the gap that currently exists between the diagnostic tests that detect important phenotypic and genetic changes in the clinical assessment of leukemia and other hematological malignancies or blood-based disorders. We have developed an "Immuno-flowFISH" method that leverages the quantitative and multi-parametric power of imaging flow cytometry to push the limits of single-cell analysis. Immuno-flowFISH has been fully optimized to detect clinically significant numerical and structural chromosomal abnormalities (i.e., trisomy 12 and del(17p)) within clonal CD19/CD5+ CD3- Chronic Lymphocytic Leukemia (CLL) cells in a single test. This integrated methodology has greater accuracy and precision than standard fluorescence in situ hybridization (FISH). We have detailed this immuno-flowFISH application with a carefully catalogued workflow, technical instructions, and a repertoire of quality control considerations to supplement the analysis of CLL. This next-generation imaging flow cytometry protocol may provide unique advancements and opportunities in the holistic cellular assessment of disease for both research and clinical laboratory settings.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , In Situ Hybridization, Fluorescence/methods , Chromosome Aberrations , Trisomy , Flow Cytometry
18.
J Exp Med ; 220(5)2023 05 01.
Article in English | MEDLINE | ID: mdl-36884218

ABSTRACT

STAT6 (signal transducer and activator of transcription 6) is a transcription factor that plays a central role in the pathophysiology of allergic inflammation. We have identified 16 patients from 10 families spanning three continents with a profound phenotype of early-life onset allergic immune dysregulation, widespread treatment-resistant atopic dermatitis, hypereosinophilia with esosinophilic gastrointestinal disease, asthma, elevated serum IgE, IgE-mediated food allergies, and anaphylaxis. The cases were either sporadic (seven kindreds) or followed an autosomal dominant inheritance pattern (three kindreds). All patients carried monoallelic rare variants in STAT6 and functional studies established their gain-of-function (GOF) phenotype with sustained STAT6 phosphorylation, increased STAT6 target gene expression, and TH2 skewing. Precision treatment with the anti-IL-4Rα antibody, dupilumab, was highly effective improving both clinical manifestations and immunological biomarkers. This study identifies heterozygous GOF variants in STAT6 as a novel autosomal dominant allergic disorder. We anticipate that our discovery of multiple kindreds with germline STAT6 GOF variants will facilitate the recognition of more affected individuals and the full definition of this new primary atopic disorder.


Subject(s)
Asthma , Food Hypersensitivity , Humans , STAT6 Transcription Factor , Gain of Function Mutation , Immunoglobulin E/genetics
19.
Hematol Oncol Clin North Am ; 37(2): 301-312, 2023 04.
Article in English | MEDLINE | ID: mdl-36907604

ABSTRACT

ß-thalassemia is caused by mutations that reduce ß-globin production, causing globin chain imbalance, ineffective erythropoiesis, and consequent anemia. Increased fetal hemoglobin (HbF) levels can ameliorate the severity of ß-thalassemia by compensating for the globin chain imbalance. Careful clinical observations paired with population studies and advances in human genetics have enabled the discovery of major regulators of HbF switching (i.e. BCL11A, ZBTB7A) and led to pharmacological and genetic therapies for treating ß-thalassemia patients. Recent functional screens using genome editing and other emerging tools have identified many new HbF regulators, which may improve therapeutic HbF induction in the future.


Subject(s)
Fetal Hemoglobin , beta-Thalassemia , Humans , Fetal Hemoglobin/genetics , beta-Thalassemia/genetics , DNA-Binding Proteins , Cell Line, Tumor , Transcription Factors
20.
medRxiv ; 2023 Mar 28.
Article in English | MEDLINE | ID: mdl-36993312

ABSTRACT

Human genetic variation has enabled the identification of several key regulators of fetal-to-adult hemoglobin switching, including BCL11A, resulting in therapeutic advances. However, despite the progress made, limited further insights have been obtained to provide a fuller accounting of how genetic variation contributes to the global mechanisms of fetal hemoglobin (HbF) gene regulation. Here, we have conducted a multi-ancestry genome-wide association study of 28,279 individuals from several cohorts spanning 5 continents to define the architecture of human genetic variation impacting HbF. We have identified a total of 178 conditionally independent genome-wide significant or suggestive variants across 14 genomic windows. Importantly, these new data enable us to better define the mechanisms by which HbF switching occurs in vivo. We conduct targeted perturbations to define BACH2 as a new genetically-nominated regulator of hemoglobin switching. We define putative causal variants and underlying mechanisms at the well-studied BCL11A and HBS1L-MYB loci, illuminating the complex variant-driven regulation present at these loci. We additionally show how rare large-effect deletions in the HBB locus can interact with polygenic variation to influence HbF levels. Our study paves the way for the next generation of therapies to more effectively induce HbF in sickle cell disease and ß-thalassemia.

SELECTION OF CITATIONS
SEARCH DETAIL
...