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1.
Sci Transl Med ; 14(670): eabn7336, 2022 11 09.
Article in English | MEDLINE | ID: mdl-36350986

ABSTRACT

Chimeric antigen receptor (CAR) T cells have not induced meaningful clinical responses in solid tumors. Loss of T cell stemness, poor expansion capacity, and exhaustion during prolonged tumor antigen exposure are major causes of CAR T cell therapeutic resistance. Single-cell RNA-sequencing analysis of CAR T cells from a first-in-human trial in metastatic prostate cancer identified two independently validated cell states associated with antitumor potency or lack of efficacy. Low expression of PRDM1, encoding the BLIMP1 transcription factor, defined highly potent TCF7 [encoding T cell factor 1 (TCF1)]-expressing CD8+ CAR T cells, whereas enrichment of HAVCR2 [encoding T cell immunoglobulin and mucin-domain containing-3 (TIM-3)]-expressing CD8+ T cells with elevated PRDM1 was associated with poor outcomes. PRDM1 knockout promoted TCF7-dependent CAR T cell stemness and proliferation, resulting in marginally enhanced leukemia control in mice. However, in the setting of PRDM1 deficiency, a negative epigenetic feedback program of nuclear factor of activated T cells (NFAT)-driven T cell dysfunction was identified. This program was characterized by compensatory up-regulation of NR4A3 and other genes encoding exhaustion-related transcription factors that hampered T cell effector function in solid tumors. Dual knockout of PRDM1 and NR4A3 skewed CAR T cell phenotypes away from TIM-3+CD8+ and toward TCF1+CD8+ to counter exhaustion of tumor-infiltrating CAR T cells and improve antitumor responses, effects that were not achieved with PRDM1 and NR4A3 single knockout alone. These data underscore dual targeting of PRDM1 and NR4A3 as a promising approach to advance adoptive cell immuno-oncotherapy.


Subject(s)
Neoplasms , Receptors, Steroid , Male , Humans , Mice , Animals , Transcription Factors/genetics , Transcription Factors/metabolism , CD8-Positive T-Lymphocytes , Immunotherapy, Adoptive/methods , Hepatitis A Virus Cellular Receptor 2/genetics , Hepatitis A Virus Cellular Receptor 2/metabolism , Neoplasms/pathology , Cell Line, Tumor , DNA-Binding Proteins/metabolism , Receptors, Steroid/metabolism , Receptors, Thyroid Hormone/metabolism , Nerve Tissue Proteins/metabolism
2.
J Matern Fetal Neonatal Med ; 35(25): 7093-7101, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34210207

ABSTRACT

Objective: To determine whether vaginal progesterone reduces spontaneous preterm birth (sPTB) before 37 weeks in asymptomatic high-risk women with a singleton pregnancy and normal mid-gestation cervical length.Study design: Databases were searched (from inception to December 2020) with the search terms "progesterone" and "premature birth" or "preterm birth". Studies were screened and included if they assessed vaginal progesterone compared to placebo in women with normal cervical length. Data were pooled and synthesized in a meta-analysis using a random effects model.Data sources: MEDLINE and Embase databases.Study synthesis: Following PRISMA screening guidelines, data from 1127 women across three studies were available for synthesis. All studies had low risk of bias and were of high quality. The primary outcome was sPTB <37 weeks, with secondary outcomes of sPTB <34 weeks. Vaginal progesterone did not significantly reduce sPTB before 37 weeks, or before 34 weeks with a relative risk (RR) of 0.76 (95% CI 0.37-1.55, p = .45) and 0.51 (95% CI 0.12-2.13, p = .35), respectively.Conclusions: Vaginal progesterone does not decrease the risk of sPTB in high-risk singleton pregnancies with a normal mid-gestation cervical length.


Subject(s)
Premature Birth , Progesterone , Pregnancy , Infant, Newborn , Female , Humans , Administration, Intravaginal , Premature Birth/prevention & control , Cervix Uteri/diagnostic imaging , Pregnancy, High-Risk , Cervical Length Measurement
3.
ACS Appl Mater Interfaces ; 13(51): 60852-60864, 2021 Dec 29.
Article in English | MEDLINE | ID: mdl-34914872

ABSTRACT

Cerium oxide nanoparticles (CeONP), having potent antioxidant properties, are highly promising nanomaterials for treatment of diseases in which oxidative stress from excessive reactive oxygen species (ROS) plays a critical role in the pathogenesis and progression. However, most previously reported CeONP formulations were not efficiently cleared from the body, precluding their clinical translation. Herein, we report ultrasmall CeONP that can mitigate activation of macrophages and subsequent acute inflammation. It is found that these CeONP can effectively scavenge reactive species, inhibit macrophage activation, and minimize their recruitment and infiltration to the inflammation site, which lead to alleviation of edema and pain hypersensitivity. Moreover, we demonstrate that CeONP can be effectively excreted from the body within 24 h of systemic administration, minimizing long-term toxicity concerns. Altogether, our findings suggest that CeONP may be explored as both antioxidant and anti-inflammatory agents that can reduce acute inflammation with a better safety profile than existing nanoparticles.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antioxidants/pharmacology , Biocompatible Materials/pharmacology , Cerium/pharmacology , Inflammation/drug therapy , Nanoparticles/chemistry , Acute Disease , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Antioxidants/chemistry , Biocompatible Materials/chemical synthesis , Biocompatible Materials/chemistry , Cerium/chemistry , Citric Acid/chemistry , Edema/drug therapy , Edema/metabolism , Freund's Adjuvant , Humans , Inflammation/metabolism , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Male , Materials Testing , Mice , Mice, Inbred C57BL , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Pain/drug therapy , Pain/metabolism
4.
Ultrasound Obstet Gynecol ; 58(5): 688-697, 2021 Nov.
Article in English | MEDLINE | ID: mdl-32851709

ABSTRACT

OBJECTIVES: Pre-eclampsia (PE) causes substantial maternal and neonatal mortality and morbidity. In addition to the personal impact on women, children and their families, PE has a significant economic impact on our society. Recent research suggests that a first-trimester multivariate model is highly predictive of preterm (< 37 weeks' gestation) PE and can be combined successfully with targeted prophylaxis (low-dose aspirin), resulting in an 80% reduction in prevalence of disease. The aim of this study was to examine the potential health outcomes and cost implications following introduction of first-trimester prediction and prevention of preterm PE within a public healthcare setting, compared with usual care, and to conduct a cost-effectiveness analysis to inform health-service decisions regarding implementation of such a program. METHODS: A decision-analytic model was used to compare usual care with the proposed first-trimester screening intervention within the obstetric population (n = 6822) attending two public hospitals within a metropolitan district health service in New South Wales, Australia, between January 2015 and December 2016. The model, applied from early pregnancy, included exposure to a variety of healthcare professionals and addressed type of risk assessment (usual care or first-trimester screening) and use of (compliance with) low-dose aspirin prescribed prophylactically for prevention of PE. All pathways culminated in six possible health outcomes, ranging from no PE to maternal death. Results were presented as the number of cases of PE gained/avoided and the incremental increase/decrease in economic costs arising from the intervention compared with usual care. Significant assumptions were tested in sensitivity/uncertainty analyses. RESULTS: The intervention produced, across all gestational ages, 31 fewer cases of PE and reduced aggregate economic health-service costs by 1 431 186 Australian dollars over the 2-year period. None of the tested iterations of uncertainty analyses reported additional cases of PE or higher economic costs. The new intervention based on first-trimester screening dominated usual care. CONCLUSION: This cost-effectiveness analysis demonstrated a reduction in prevalence of preterm PE and substantial cost savings associated with a population-based program of first-trimester prediction and prevention of PE, and supports implementation of such a policy. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Clinical Decision Rules , Pre-Eclampsia/diagnosis , Pre-Eclampsia/economics , Prenatal Diagnosis/economics , Adult , Cost-Benefit Analysis , Female , Health Plan Implementation , Humans , New South Wales/epidemiology , Pre-Eclampsia/epidemiology , Predictive Value of Tests , Pregnancy , Pregnancy Trimester, First , Premature Birth/diagnosis , Premature Birth/economics , Premature Birth/epidemiology , Prenatal Diagnosis/methods , Prevalence , Program Evaluation , Risk Assessment
5.
Physiol Genomics ; 51(3): 90-96, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30707046

ABSTRACT

Acute kidney injury (AKI) is an increasing clinical problem that is associated with chronic kidney disease progression. Cannabinoid receptor 2 (CB2) activation has been shown to mitigate some of the deleterious tubular effects due to AKI, but its role on the renal vasculature has not been fully described. In this study, we investigated the effects of our novel CB2 receptor agonist, SMM-295, on renal vasculature by assessing cortical perfusion with laser Doppler flowmetry and changes in luminal diameter with isolated afferent arterioles. In this study, intravenously infused SMM-295 (6 mg/kg) significantly increased cortical renal perfusion (13.8 ± 0.6%; P < 0.0001; n = 7) compared with vehicle (0.1 ± 1.5%; n = 10) normalized to baseline values in anesthetized C57BL/6J mice. This effect was not dependent upon activation of the CB1 receptor (met-anandamide; 6 mg/kg iv) and was predominantly abolished in Cnr2 knockout mice with SMM-295 (6 mg/kg iv). Ablation of the renal afferent nerves with capsaicin blocked the SMM-295-dependent increase in renal cortical perfusion, and the increased renal blood flow was not dependent upon products synthesized by cyclooxygenase or nitric oxide synthase. The increased renal perfusion by CB2 receptor activation is also attributed to a direct vascular effect, since SMM-295 (5 µM) engendered a significant 37 ± 7% increase ( P < 0.0001; n = 4) in luminal diameters of norepinephrine-preconstricted afferent arterioles. These data provide new insight into the potential benefit of SMM-295 by activating vascular and nonvascular CB2 receptors to promote renal vasodilation, and provide a new therapeutic target to treat renal injuries that impact renal blood flow dynamics.


Subject(s)
Acute Kidney Injury/drug therapy , Acute Kidney Injury/metabolism , Receptor, Cannabinoid, CB2/agonists , Receptor, Cannabinoid, CB2/metabolism , Renal Circulation/drug effects , Vasodilator Agents/therapeutic use , Animals , Arachidonic Acids/administration & dosage , Arachidonic Acids/therapeutic use , Cannabinoid Receptor Agonists/administration & dosage , Cannabinoid Receptor Agonists/therapeutic use , Disease Models, Animal , Endocannabinoids/administration & dosage , Endocannabinoids/therapeutic use , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Gene Knockout Techniques , Mice , Mice, Inbred C57BL , Mice, Knockout , Nitric Oxide Synthase/metabolism , Polyunsaturated Alkamides/administration & dosage , Polyunsaturated Alkamides/therapeutic use , Prostaglandin-Endoperoxide Synthases/metabolism , Receptor, Cannabinoid, CB1/agonists , Receptor, Cannabinoid, CB1/metabolism , Receptor, Cannabinoid, CB2/genetics , Vasodilation/drug effects , Vasodilator Agents/administration & dosage
6.
Vet Rec ; 179(16): 412-413, 2016 Oct 22.
Article in English | MEDLINE | ID: mdl-27770094

ABSTRACT

Adopting the concept of One Welfare could help to improve animal welfare and human wellbeing worldwide, argue Rebeca García Pinillos, Michael Appleby, Xavier Manteca, Freda Scott-Park, Charles Smith and Antonio Velarde.


Subject(s)
Animal Welfare/organization & administration , Cooperative Behavior , Global Health , Animals , Humans
8.
Bioinspir Biomim ; 10(5): 055008, 2015 Oct 06.
Article in English | MEDLINE | ID: mdl-26440578

ABSTRACT

Digital implementations of control laws typically involve discretization with respect to both time and space, and a control law that can achieve a task at coarser levels of discretization can be said to require less control attention, and also reduced implementation costs. One means of quantitatively capturing the attention of a control law is to measure the rate of change of the control with respect to changes in state and time. In this paper we present an attention-minimizing control law for ball catching and other target tracking tasks based on Brockett's attention criterion. We first highlight the connections between this attention criterion and some well-known principles from human motor control. Under the assumption that the optimal control law is the sum of a linear time-varying feedback term and a time-varying feedforward term, we derive an LQR-based minimum attention tracking control law that is stable, and obtained efficiently via a finite-dimensional optimization over the symmetric positive-definite matrices. Taking ball catching as our primary task, we perform numerical experiments comparing the performance of the various control strategies examined in the paper. Consistent with prevailing theories about human ball catching, our results exhibit several familiar features, e.g., the transition from open-loop to closed-loop control during the catching movement, and improved robustness to spatiotemporal discretization. The presented control laws are applicable to more general tracking problems that are subject to limited communication resources.


Subject(s)
Attention/physiology , Baseball/physiology , Biomimetics/methods , Models, Neurological , Motion Perception/physiology , Robotics/methods , Algorithms , Arm/physiology , Athletic Performance/physiology , Computer Simulation , Computer-Aided Design , Feedback, Physiological/physiology , Humans , Robotics/instrumentation
9.
Ultrasound Obstet Gynecol ; 46(4): 419-23, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25678383

ABSTRACT

OBJECTIVE: To examine the effect of a combination of screening and treatment with low-dose aspirin on the prevalence of early-onset pre-eclampsia (PE). METHODS: This was a retrospective analysis of two consecutive cohorts of women screened for early PE. The first cohort was observed to determine whether algorithms developed to screen for PE at 11 to 13 + 6 weeks' gestation could be applied to our population. High-risk women in the second cohort were advised on their risk and offered aspirin (150 mg at night), with treatment starting immediately after screening. The prevalence of early PE and the proportion of women with PE delivering at 34-37 weeks' gestation were compared between the cohorts. RESULTS: In the observational and interventional cohorts, 3066 and 2717 women, respectively, were screened. There were 12 (0.4%) cases of early PE in the observational cohort and one (0.04%) in the interventional cohort (P < 0.01). Among all women with PE delivering before 37 weeks, 25 (0.83%) were in the observational cohort and 10 (0.37%) in the interventional cohort (P = 0.03). CONCLUSIONS: A strategy of first-trimester screening for early PE coupled with prescription of aspirin to the high-risk group appears to be effective in reducing the prevalence of early PE.


Subject(s)
Aspirin/administration & dosage , Platelet Aggregation Inhibitors/administration & dosage , Pre-Eclampsia/prevention & control , Adult , Australia/epidemiology , Cohort Studies , Female , Gestational Age , Humans , Infant, Newborn , Pre-Eclampsia/diagnosis , Pre-Eclampsia/diagnostic imaging , Pre-Eclampsia/epidemiology , Predictive Value of Tests , Pregnancy , Pregnancy Outcome , Pregnancy Trimester, First , Retrospective Studies , Risk Factors , Ultrasonography, Doppler, Pulsed/methods
10.
J Vet Intern Med ; 27(5): 1136-42, 2013.
Article in English | MEDLINE | ID: mdl-24033421

ABSTRACT

BACKGROUND: Dogs with hyperadrenocorticism are at risk of thromboembolic disease, which might be caused by an underlying hypercoagulable state. HYPOTHESIS/OBJECTIVES: To assess hemostatic function in dogs with ACTH-dependent hyperadrenocorticism (ADHAC) before and after treatment. ANIMALS: Nineteen dogs with ADHAC and 40 normal dogs. METHODS: Prospective, observational study. Dogs with ADHAC were recruited from the referral hospital patient population; normal dogs were recruited from staff and students at the study's institution. Hemostasis was assessed before and at 3 and 6 months after treatment with trilostane (T0, T3, T6) by kaolin-activated thrombelastography with platelet mapping (TEG-PM), prothrombin time, activated partial thromboplastin time, fibrinogen concentration, and antithrombin activity (AT). RESULTS: Dogs with ADHAC had statistically significantly increased α-angle (P < .01) and maximum amplitude (MA)(thrombin) (P < .01) on TEG-PM, and significantly decreased κ (P < .005) at T0, T3, and T6. Platelet count (P < .001) and fibrinogen concentration (P < .001), but not AT activity, were increased in dogs with ADHAC at T0, T3, and T6. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with ADHAC have thrombelastographic evidence of hypercoagulability and remained hypercoagulable during treatment. AT deficiency does not appear to be involved in the pathogenesis of hypercoagulability in this population.


Subject(s)
Dog Diseases/etiology , Hyperaldosteronism/veterinary , Thrombophilia/veterinary , Animals , Blood Chemical Analysis , Dog Diseases/blood , Dog Diseases/pathology , Dogs , Hyperaldosteronism/complications , Hyperaldosteronism/pathology , Thrombelastography/veterinary , Thrombophilia/blood , Thrombophilia/complications , Thrombophilia/pathology
11.
Cell ; 153(3): 614-27, 2013 Apr 25.
Article in English | MEDLINE | ID: mdl-23622245

ABSTRACT

Protein degradation by the ubiquitin-proteasome system is central to cell homeostasis and survival. Defects in this process are associated with diseases such as cancer and neurodegenerative disorders. The 26S proteasome is a large protease complex that degrades ubiquitinated proteins. Here, we show that ADP-ribosylation promotes 26S proteasome activity in both Drosophila and human cells. We identify the ADP-ribosyltransferase tankyrase (TNKS) and the 19S assembly chaperones dp27 and dS5b as direct binding partners of the proteasome regulator PI31. TNKS-mediated ADP-ribosylation of PI31 drastically reduces its affinity for 20S proteasome α subunits to relieve 20S repression by PI31. Additionally, PI31 modification increases binding to and sequestration of dp27 and dS5b from 19S regulatory particles, promoting 26S assembly. Inhibition of TNKS by either RNAi or a small-molecule inhibitor, XAV939, blocks this process to reduce 26S assembly. These results unravel a mechanism of proteasome regulation that can be targeted with existing small-molecule inhibitors.


Subject(s)
Drosophila melanogaster/metabolism , Proteasome Endopeptidase Complex/metabolism , Tankyrases/metabolism , Amino Acid Motifs , Amino Acid Sequence , Animals , Carrier Proteins/metabolism , Drosophila Proteins/metabolism , HEK293 Cells , Humans , Molecular Sequence Data , Protein Structure, Tertiary , Sequence Alignment
13.
Aust Vet J ; 89(3): 82-8, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21323655

ABSTRACT

BACKGROUND: Studies of avian trichomoniasis in the literature are limited to some extent, often being confined to a single bird species or group of species within a bird Order. Some incidence studies have been reported for free-living birds, and occasionally for captive birds. Very few reports describe the prevalence and types of lesions seen for a wide range of bird species, especially from a clinical perspective. METHODS: Retrospective study of avian practice records from a 10-year period. Emphasis on the types of presentations and relative prevalence of trichomoniasis in a variety of captive and free-living bird species encountered in Australian avian practice. RESULTS: The occurrence of trichomoniasis in several novel species (lorikeets, corvids and a cuckoo species), plus its distinctive presentation in southern boobook owls (Ninox boobook), is documented. CONCLUSION: Trichomoniasis should be a differential diagnosis for birds presenting with regurgitation or upper gastrointestinal abscesses, even if motile trichomonads are not found in wet preparations from crop washes or lesions.


Subject(s)
Bird Diseases/epidemiology , Bird Diseases/pathology , Trichomonas Infections/veterinary , Animals , Animals, Wild , Australia/epidemiology , Birds , Female , Male , Prevalence , Retrospective Studies , Species Specificity , Trichomonas Infections/epidemiology , Trichomonas Infections/pathology
14.
Aust Vet J ; 87(6): 249-52, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19489784

ABSTRACT

Two young adult male castrated German Shepherd Dogs were referred for evaluation of intermittent episodes of hindlimb pain. Physical examination suggested lumbosacral stenosis, and plain radiographs and computed tomography revealed lesions consistent with sacral osteochondrosis. One dog had osteochondral fragments removed surgically; the other was managed conservatively. The surgically treated dog had complete resolution of clinical signs whereas the dog managed conservatively had repeated episodes of mild pain and received one short course of non-steroidal anti-inflammatory medication in 18 months. Sacral osteochondrosis has not been previously reported in Australia.


Subject(s)
Dog Diseases/drug therapy , Dog Diseases/surgery , Sacrum , Spinal Osteochondrosis/veterinary , Animals , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Dog Diseases/diagnostic imaging , Dogs , Hindlimb , Male , Pain/diagnosis , Pain/etiology , Pain/veterinary , Sacrum/diagnostic imaging , Spinal Osteochondrosis/diagnostic imaging , Spinal Osteochondrosis/drug therapy , Spinal Osteochondrosis/surgery , Tomography, X-Ray Computed/veterinary , Treatment Outcome
15.
Aust Vet J ; 87(1): 63-5, 2009.
Article in English | MEDLINE | ID: mdl-19178482

ABSTRACT

A nestling Derbyan parrot (Psittacula derbiana) was presented with unusual subcutaneous swellings of the thigh regions, and poor growth. Histological examination revealed actinomycetous bacteria associated with multifocal systemic granulomas. The clinical and pathological findings of the case are presented, and some relevant aspects of actinomycetous bacterial infections in mammals and birds are discussed. Although granulomatous disease is encountered at times in avian species, the actinomycetous bacteria (Nocardia and Actinomyces spp.) have rarely been reported in association with multifocal granulomatous disease in birds.


Subject(s)
Actinomycosis/veterinary , Bird Diseases/diagnosis , Granuloma/veterinary , Nocardia Infections/veterinary , Parrots/microbiology , Actinomyces/isolation & purification , Actinomycosis/diagnosis , Actinomycosis/pathology , Animals , Animals, Newborn , Bird Diseases/pathology , Granuloma/diagnosis , Granuloma/pathology , Immunohistochemistry/veterinary , Nocardia/isolation & purification , Nocardia Infections/diagnosis , Nocardia Infections/pathology
16.
Curr Biol ; 16(20): 2035-41, 2006 Oct 24.
Article in English | MEDLINE | ID: mdl-17055983

ABSTRACT

In the early Drosophila embryo, asymmetric distribution of transcription factors, established as a consequence of translational control of their maternally derived mRNAs, initiates pattern formation . For instance, translation of the uniformly distributed maternal hunchback (hb) mRNA is inhibited at the posterior to form an anterior-to-posterior protein concentration gradient along the longitudinal axis . Inhibition of hb mRNA translation requires an mRNP complex (the NRE complex), which consists of Nanos (Nos), Pumilio (Pum), and Brain tumor (Brat) proteins, and the Nos responsive element (NRE) present in the 3' UTR of hb mRNA . The identity of the mRNA 5' effector protein that is responsible for this translational inhibition remained elusive. Here we show that d4EHP, a cap binding protein that represses caudal (cad) mRNA translation , also inhibits hb mRNA translation by interacting simultaneously with the mRNA 5' cap structure (m(7)GpppN, where N is any nucleotide) and Brat. Thus, by regulating Cad and Hb expression, d4EHP plays a key role in establishing anterior-posterior axis polarity in the Drosophila embryo.


Subject(s)
Body Patterning/physiology , Drosophila Proteins/metabolism , Drosophila/embryology , Eukaryotic Initiation Factor-4E/metabolism , Gene Expression Regulation, Developmental/physiology , RNA, Messenger, Stored/metabolism , Animals , Blotting, Western , Cloning, Molecular , DNA-Binding Proteins/immunology , DNA-Binding Proteins/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/immunology , Embryo, Nonmammalian/physiology , Eukaryotic Initiation Factor-4E/genetics , Fluorescent Antibody Technique , Homeodomain Proteins/metabolism , Plasmids/genetics , Transcription Factors/metabolism
17.
Structure ; 14(5): 913-23, 2006 May.
Article in English | MEDLINE | ID: mdl-16698552

ABSTRACT

The X-ray structure of the C-terminal region of human eukaryotic translation initiation factor 4G (eIF4G) has been determined at 2.2 A resolution, revealing two atypical HEAT-repeat domains. eIF4G recruits various translation factors and the 40S ribosomal subunit to the mRNA 5' end. In higher eukaryotes, the C terminus of eIF4G (4G/C) supports translational regulation by recruiting eIF4A, an RNA helicase, and Mnk1, the kinase responsible for phosphorylating eIF4E. Structure-guided surface mutagenesis and protein-protein interaction assays were used to identify binding sites for eIF4A and Mnk1 within the HEAT-repeats of 4G/C. p97/DAP5, a translational modulator homologous to eIF4G, lacks an eIF4A binding site in the corresponding region. The second atypical HEAT domain of the 4G/C binds Mnk1 using two conserved aromatic/acidic-box (AA-box) motifs. Within the first AA-box, the aromatic residues contribute to the hydrophobic core of the domain, while the acidic residues form a negatively charged surface feature suitable for electrostatic interactions with basic residues in Mnk1.


Subject(s)
Eukaryotic Initiation Factor-4A/chemistry , Eukaryotic Initiation Factor-4G/chemistry , Intracellular Signaling Peptides and Proteins/chemistry , Protein Serine-Threonine Kinases/chemistry , Amino Acid Sequence , Amino Acids, Aromatic/chemistry , Amino Acids, Aromatic/genetics , Conserved Sequence , Crystallography, X-Ray , Eukaryotic Initiation Factor-4G/genetics , Humans , Models, Molecular , Molecular Sequence Data , Mutagenesis , Protein Interaction Mapping , Protein Structure, Tertiary
18.
Aust Vet J ; 83(9): 547-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16164142

ABSTRACT

A wild Peregrine Falcon (Falco peregrinus) was presented with extensive bilateral fluorescein positive corneal damage. Local therapy and bilateral tarsorrhaphies resulted in slow improvement over 5 weeks. When bilateral 360 degree conjunctival flaps were used subsequently, healing proceeded more rapidly over the next 8 weeks. Although bulbar conjunctival flaps have been reported as difficult in birds due to their small size and relatively immobile bulbar conjunctiva, 360 degree conjunctival flaps made from palpebral rather than bulbar conjunctiva were found to be technically feasible in a larger bird species such as the Peregrine Falcon.


Subject(s)
Bird Diseases/surgery , Corneal Ulcer/veterinary , Falconiformes , Keratitis/veterinary , Ophthalmologic Surgical Procedures/veterinary , Animals , Animals, Wild , Bird Diseases/drug therapy , Combined Modality Therapy/veterinary , Conjunctiva/surgery , Corneal Ulcer/drug therapy , Corneal Ulcer/surgery , Female , Keratitis/drug therapy , Keratitis/surgery , Ophthalmologic Surgical Procedures/methods , Surgical Flaps/veterinary , Treatment Outcome
19.
Proteins ; 60(4): 787-96, 2005 Sep 01.
Article in English | MEDLINE | ID: mdl-16021622

ABSTRACT

The targets of the Structural GenomiX (SGX) bacterial genomics project were proteins conserved in multiple prokaryotic organisms with no obvious sequence homolog in the Protein Data Bank of known structures. The outcome of this work was 80 structures, covering 60 unique sequences and 49 different genes. Experimental phase determination from proteins incorporating Se-Met was carried out for 45 structures with most of the remainder solved by molecular replacement using members of the experimentally phased set as search models. An automated tool was developed to deposit these structures in the Protein Data Bank, along with the associated X-ray diffraction data (including refined experimental phases) and experimentally confirmed sequences. BLAST comparisons of the SGX structures with structures that had appeared in the Protein Data Bank over the intervening 3.5 years since the SGX target list had been compiled identified homologs for 49 of the 60 unique sequences represented by the SGX structures. This result indicates that, for bacterial structures that are relatively easy to express, purify, and crystallize, the structural coverage of gene space is proceeding rapidly. More distant sequence-structure relationships between the SGX and PDB structures were investigated using PDB-BLAST and Combinatorial Extension (CE). Only one structure, SufD, has a truly unique topology compared to all folds in the PDB.


Subject(s)
Escherichia coli Proteins/chemistry , Escherichia coli/genetics , Genome, Bacterial , Genomics , Databases, Protein , Enzymes/chemistry , Enzymes/genetics , Escherichia coli Proteins/genetics , Models, Molecular , Protein Conformation , Regression Analysis , X-Ray Diffraction
20.
Cell ; 121(3): 411-23, 2005 May 06.
Article in English | MEDLINE | ID: mdl-15882623

ABSTRACT

Translational control is a key genetic regulatory mechanism implicated in regulation of cell and organismal growth and early embryonic development. Initiation at the mRNA 5' cap structure recognition step is frequently targeted by translational control mechanisms. In the Drosophila embryo, cap-dependent translation of the uniformly distributed caudal (cad) mRNA is inhibited in the anterior by Bicoid (Bcd) to create an asymmetric distribution of Cad protein. Here, we show that d4EHP, an eIF4E-related cap binding protein, specifically interacts with Bcd to suppress cad translation. Translational inhibition depends on the Bcd binding region (BBR) present in the cad 3' untranslated region. Thus, simultaneous interactions of d4EHP with the cap structure and of Bcd with BBR renders cad mRNA translationally inactive. This example of cap-dependent translational control that is not mediated by canonical eIF4E defines a new paradigm for translational inhibition involving tethering of the mRNA 5' and 3' ends.


Subject(s)
Drosophila Proteins/physiology , Eukaryotic Initiation Factor-4E/genetics , Gene Expression Regulation, Developmental , Homeodomain Proteins/metabolism , Protein Biosynthesis/genetics , RNA, Messenger/metabolism , Trans-Activators/metabolism , 3' Untranslated Regions/genetics , Amino Acid Sequence , Animals , Binding Sites/genetics , Body Patterning/genetics , Cell Line , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/embryology , Drosophila melanogaster/genetics , Drosophila melanogaster/physiology , Embryo, Nonmammalian/embryology , Embryo, Nonmammalian/metabolism , Eukaryotic Initiation Factor-4E/metabolism , Eukaryotic Initiation Factor-4E/physiology , Homeodomain Proteins/genetics , Humans , Models, Biological , Molecular Sequence Data , Mutation , Protein Binding/genetics , RNA Cap-Binding Proteins/genetics , RNA Cap-Binding Proteins/metabolism , RNA Caps/metabolism , Sequence Homology, Amino Acid , Trans-Activators/genetics , Transcription Factors/genetics , Transcription Factors/metabolism
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