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2.
PeerJ ; 12: e16799, 2024.
Article in English | MEDLINE | ID: mdl-38288463

ABSTRACT

Background: In 2020, 203 million people experienced neck pain, with a higher prevalence in women. By 2050, it is predicted that neck pain will affect 269 million people, representing a 32.5% increase. Physical rehabilitation is often employed for the treatment of chronic non-specific neck pain (CNSNP) and the associated functional loss. Taping is frequently used as an adjunct treatment alongside primary physical rehabilitation. Unlike kinesio tape (KT), the therapeutic benefits of dynamic tape (DT) have not been thoroughly explored and documented in non-athletic conditions. Therefore, the aim of this trial was to determine the effects of DT on pain, disability, and overall well-being in individuals experiencing CNSNP. Methods: A prospective parallel-group active controlled trial was conducted at a single center, involving 136 patients with CNSNP, randomly allocated in a 1:1 ratio. The sham taping group (STC) received standard physiotherapy care (n = 67) alongside DT without tension, while the dynamic taping group (DTC) (n = 69) underwent standard cervical offloading technique with appropriate tension in addition to standard physiotherapy care. Demographic information and three patient-reported outcome measures (PROMs), namely the Neck Disability Index (NDI), Visual Analogue Scale (VAS), and the World Health Organization-Five Well-Being Index (WHO-5), were collected for each participant at three time points (baseline, four weeks post-taping, and four weeks follow-up). Results: At baseline, no significant differences were observed between the STC and DTC for any outcome measure. Notably, all three PROMs exhibited a significant improvement from baseline to four weeks post-intervention, with moderate to small effect sizes (NDI ηp2 = 0.21, VAS ηp2 = 0.23, and WHO-55 ηp2 = 0.05). The WHO-5 scores for both groups demonstrated improvement from baseline through follow-up (p < 0.001). The NDI and VAS scores ameliorated from baseline to the four weeks post-taping period, with marginal improvements observed during the four weeks follow-up. Conclusion: The incorporation of DT as an adjunct to standard physiotherapy care yielded enhancements in pain levels, functional disability, and well-being among patients with CNSNP when compared to the sham group. However, the sustainability of these improvements beyond the taping period lacks statistical significance and warrants further validation.


Subject(s)
Chronic Pain , Neck Pain , Humans , Female , Neck Pain/therapy , Quality of Life , Prospective Studies , Chronic Pain/therapy , Neck
3.
JCEM Case Rep ; 1(3): luad051, 2023 May.
Article in English | MEDLINE | ID: mdl-37908577

ABSTRACT

Graves' disease is the most common cause of pediatric hyperthyroidism and thyrotoxicosis. Thyroid storm is a rare initial manifestation of Graves' disease and represents an endocrine emergency. We report a case of transient hyperthyroidism, possibly a paraneoplastic syndrome presenting as impending thyroid storm in a patient with undiagnosed hepatoblastoma. To our knowledge, this is the first case of this association reported in children. A previously healthy 21-month-old male presented with abdominal pain and unremitting tachycardia. He was managed for thyrotoxicosis and impending thyroid storm. He subsequently was found to have hepatomegaly leading to a diagnosis of hepatoblastoma. Autoimmune markers for Graves' disease were negative, along with a negative human chorionic gonadotropin. After initiation of neoadjuvant chemotherapy, he had complete resolution of thyrotoxicosis. Paraneoplastic syndromes may occur with any tumor. We present a unique case of a patient developing human chorionic gonadotropin-negative hyperthyroidism, possibly as a paraneoplastic syndrome from hepatoblastoma.

4.
Psychoneuroendocrinology ; 151: 106071, 2023 05.
Article in English | MEDLINE | ID: mdl-36857833

ABSTRACT

There is continued interest in identifying dysregulated biomarkers that mediate associations between adverse childhood experiences (ACEs) and negative long-term health outcomes. However, little is known regarding how ACE exposure modulates neural biomarkers to influence poorer health outcomes in ACE-exposed children. To address this, we performed a systematic review and meta-analysis of the impact of ACE exposure on Brain Derived Neurotrophic Factor (BDNF) levels - a neural biomarker involved in childhood and adult neurogenesis and long-term memory formation. Twenty-two studies were selected for inclusion within the systematic review, ten of which were included in meta-analysis. Most included studies retrospectively assessed impacts of childhood maltreatment in clinical populations. Sample size, BDNF protein levels in ACE-exposed and unexposed subjects, and standard deviations were extracted from ten publications to estimate the BDNF ratio of means (ROM) across exposure categories. Overall, no significant difference was found in BDNF protein levels between ACE-exposed and unexposed groups (ROM: 1.08; 95 % CI: 0.93-1.26). Age at sampling, analyte type (e.g., sera, plasma, blood), and categories of ACE exposure contributed to high between-study heterogeneity, some of which was minimized in subset-based analyses. These results support continued investigation into the impact of ACE exposure on neural biomarkers and highlight the potential importance of analyte type and timing of sample collection on study results.


Subject(s)
Adverse Childhood Experiences , Brain-Derived Neurotrophic Factor , Child , Adult , Humans , Retrospective Studies , Biomarkers
5.
Indian J Hematol Blood Transfus ; 39(1): 90-101, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36699436

ABSTRACT

Anemia remains a significant public health challenge, disproportionately impacting lower-income patients residing in areas of lesser healthcare resources. We sought to evaluate the accuracy of physical exam techniques to diagnose anemia among patients 5 years of age or older. A systematic review of 5 databases (MEDLINE via OVID, EMBASE, Scopus, Global Health and Global Health Archives, and WHO Global Index Medicus) was conducted. Studies that (1) compared non-invasive physical exam techniques with anemia diagnoses using standard laboratory measurements and (2) solely assessed or separately reported the diagnostic accuracy of physical exam techniques for patients 5 years or older were considered for inclusion. The diagnostic accuracies of individual and combinatorial physical exam techniques todiagnose anemia were documented. This systematic review was registered with PROSPERO. The systemic literature search yielded 6,457 unique studies after removal of duplicates. Fourteen studies were ultimately selected for inclusion. Eight studies solely assessed pregnant females, 4 solely assessed hospitalized patients, and 2 evaluated the general population. The diagnostic accuracy ranged widely for pallor assessments of conjunctivae (sensitivity: 19-97%, specificity: 65-100%), nailbed (sensitivity: 41-65%, specificity: 58-93%), and palms (sensitivity: 33-91%, specificity: 54-93%). Examining 9 or more sites leads to higher sensitivity (73.8-82.9%) and specificity (76.0-90.9%). No individual examination technique is superior to others for diagnosing anemia. Combinatorial approachs are associated with more acceptable accuracy measures, but improvements need to be balanced with time available for examination. Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-022-01543-z.

6.
Biol Methods Protoc ; 7(1): bpac028, 2022.
Article in English | MEDLINE | ID: mdl-36518355

ABSTRACT

COVID-19 infections have imposed immense pressure on the healthcare system of most countries. While the initial studies have identified better therapeutic and diagnostic approaches, the disease severity is still assessed by close monitoring of symptoms by healthcare professionals due to the lack of biomarkers for disease stratification. In this study, we have probed the immune and molecular profiles of COVID-19 patients at 48-h intervals after hospitalization to identify early markers, if any, of disease progression and severity. Our study reveals that the molecular profiles of patients likely to enter the host-immune response-mediated moderate or severe disease progression are distinct even in the early phase of infection when severe symptoms are not yet apparent. Our data from 37 patients suggest that at hospitalization, interleukins (IL6) (>300 pg/ml) and IL8 levels (>200 pg/ml) identify cytokine-dependent disease progression. Monitoring their levels will facilitate timely intervention using available immunomodulators or precision medicines in those likely to progress due to cytokine storm and help improve outcomes. Additionally, it will also help identify cytokine-independent progressive patients, not likely to benefit from immunomodulators or precision drugs.

7.
Neuron ; 110(24): 4037-4039, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36549268

ABSTRACT

Goal-directed behavior is often studied under food- and water-restricted states. A study by Matteucci et al.1 in this issue of Neuron reveals that task performance and sensorimotor cortical encoding are impaired under both low and high motivational states but improve with physiological adaption.


Subject(s)
Goals , Sensorimotor Cortex , Motivation , Task Performance and Analysis , Neurons/physiology
8.
Int J Cancer ; 150(9): 1401-1411, 2022 05 01.
Article in English | MEDLINE | ID: mdl-34921734

ABSTRACT

Acute myeloid leukemia (AMLs), as the name suggests, often develop suddenly and are very progressive forms of cancer. Unlike in acute promyelocytic leukemia, a subtype of AML, the outcomes in most other AMLs remain poor. This is mainly attributed to the acquired drug resistance and lack of targeted therapy. Different studies across laboratories suggest that the cellular mechanisms to impart therapy resistance are often very dynamic and should be identified in a context-specific manner. Our review highlights the progress made so far in identifying the different cellular mechanisms of mutation-independent therapy resistance in AML. It reiterates that for more effective outcomes cancer therapies should acquire a more tailored approach where the protective interactions between the cancer cells and their niches are identified and targeted.


Subject(s)
Leukemia, Myeloid, Acute , Leukemia, Promyelocytic, Acute , Drug Resistance , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Mutation , Tumor Microenvironment
10.
Diabetes Spectr ; 34(2): 190-197, 2021 May.
Article in English | MEDLINE | ID: mdl-34149260

ABSTRACT

OBJECTIVE: In response to the coronavirus disease 2019 (COVID-19) pandemic and social distancing guidelines, our pediatric diabetes team rapidly changed the format of conducting diabetes clinic from in person to telehealth. We compared the actual number and rate of completed, canceled, and no-show visits between an 8-week period in 2019, when we exclusively conducted visits in person and the same 8-week period in 2020, during the COVID-19 quarantine, when we exclusively conducted visits via telehealth. METHODS: We used electronic health record data for all patients, as well as Dexcom continuous glucose monitoring data collected for a subset of youths during the COVID-19 quarantine and the immediate pre-COVID-19 period. RESULTS: Although there was a difference in the absolute number of in-person versus telehealth visits canceled during these two time periods, there was no difference in the rates of completed, canceled, and no-show visits completed in person or via telehealth. This finding suggests that, despite a rapid shift to a completely new health care delivery model, our providers completed a similar rate of patient care via telehealth during the COVID-19 quarantine and that telehealth may be a feasible method for providing diabetes care. However, our results also suggested that youths' glucose management was less optimal during the quarantine period. CONCLUSION: COVID-19 presented an opportunity to adopt and test the feasibility of using a telehealth delivery model for routine diabetes care. Yet, to make telehealth a viable treatment delivery alternative will likely involve the uptake of new clinic procedures, investment in institutional infrastructure, and team-based flexibility.

11.
Cell Death Dis ; 12(3): 259, 2021 03 11.
Article in English | MEDLINE | ID: mdl-33707419

ABSTRACT

Chronic myeloid leukemia (CML) patients with complex chromosomal translocations as well as non-compliant CML patients often demonstrate short-lived responses and poor outcomes on the current therapeutic regimes using Imatinib and its variants. It has been derived so far that leukemic stem cells (LSCs) are responsible for Imatinib resistance and CML progression. Sonic hedgehog (Shh) signaling has been implicated in proliferation of this Imatinib-resistant CD34(+) LSCs. Our work here identifies the molecular mechanism of Shh-mediated mutation-independent Imatinib resistance that is most relevant for treating CML-variants and non-compliant patients. Our results elucidate that while Shh can impart stemness, it also upregulates expression of anti-apoptotic protein-Bcl2. It is the upregulation of Bcl2 that is involved in conferring Imatinib resistance to the CD34(+) LSCs. Sub-toxic doses of Bcl2 inhibitor or Shh inhibitor (<

Subject(s)
Antineoplastic Agents/pharmacology , Chromosomes, Human , Drug Resistance, Neoplasm , Hedgehog Proteins/metabolism , Imatinib Mesylate/pharmacology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Neoplastic Stem Cells/drug effects , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-bcl-2/metabolism , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic , Hedgehog Proteins/antagonists & inhibitors , Hedgehog Proteins/genetics , Humans , K562 Cells , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors , Proto-Oncogene Proteins c-bcl-2/genetics , Thiazoles/pharmacology , Up-Regulation , Veratrum Alkaloids/pharmacology
12.
J Pediatr Endocrinol Metab ; 34(3): 311-317, 2021 Mar 26.
Article in English | MEDLINE | ID: mdl-33618445

ABSTRACT

OBJECTIVES: The development of continuous glucose monitoring (CGM) systems has allowed for identification of blood sugar variations and trends in real-time that is not feasible with conventional self-monitoring of blood glucose. However, there is inconsistent data to show that the use of CGM leads to better glycemic control as measured by Hemoglobin A1c (HbA1c) in pediatric patients with type 1 diabetes mellitus. Our study aimed to compare the average HbA1c level in the 1-2 years prior to starting a CGM to the average HbA1c level in the 1-2 years immediately following CGM initiation in a sample of 1-20 year olds with type 1 diabetes mellitus. METHODS: Participants were 90 youth (ages 1-20) followed for type 1 diabetes care at our institution who used a CGM for at least a 6 month time period. We performed a retrospective chart review to obtain up to four HbA1c values pre and post-CGM initiation each. We evaluated pre- and post-CGM initiation changes in mean HbA1c via dependent samples t-tests using IBM SPSS 24.0. RESULTS: The mean HbA1c was 8.7% pre-CGM and decreased to 8.27% 9-12 months after CGM initiation in the overall sample. A statistically significant decrease in HbA1c was seen in patients who used multiple daily injections (p=0.02), those with a pre-CGM HbA1c greater than 9% (p=0.01), and those with a diabetes duration of 5-10 years (p=0.02). CONCLUSION: CGM use was associated with a decrease in HbA1c over time which was statistically significant in some subgroups.


Subject(s)
Blood Glucose Self-Monitoring , Diabetes Mellitus, Type 1/metabolism , Glycated Hemoglobin/analysis , Adolescent , Blood Glucose/analysis , Child , Child, Preschool , Female , Humans , Infant , Male , Retrospective Studies , Young Adult
13.
BMC Mol Cell Biol ; 21(1): 25, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-32293249

ABSTRACT

BACKGROUND: Reversible cell cycle arrest (quiescence/G0) is characteristic of adult stem cells and is actively controlled at multiple levels. Quiescent cells also extend a primary cilium, which functions as a signaling hub. Primary cilia have been shown to be important in multiple developmental processes, and are implicated in numerous developmental disorders. Although the association of the cilium with G0 is established, the role of the cilium in the control of the quiescence program is still poorly understood. RESULTS: Primary cilia are dynamically regulated across different states of cell cycle exit in skeletal muscle myoblasts: quiescent myoblasts elaborate a primary cilium in vivo and in vitro, but terminally differentiated myofibers do not. Myoblasts where ciliogenesis is ablated using RNAi against a key ciliary assembly protein (IFT88) can exit the cell cycle but display an altered quiescence program and impaired self-renewal. Specifically, the G0 transcriptome in IFT88 knockdown cells is aberrantly enriched for G2/M regulators, suggesting a focused repression of this network by the cilium. Cilium-ablated cells also exhibit features of activation including enhanced activity of Wnt and mitogen signaling and elevated protein synthesis via inactivation of the translational repressor 4E-BP1. CONCLUSIONS: Taken together, our results show that the primary cilium integrates and dampens proliferative signaling, represses translation and G2/M genes, and is integral to the establishment of the quiescence program.


Subject(s)
Cell Cycle Checkpoints/physiology , Cilia/metabolism , Gene Regulatory Networks , Myoblasts, Skeletal/metabolism , Adaptor Proteins, Signal Transducing , Animals , Cell Cycle/physiology , Cell Cycle Proteins , Cell Differentiation , Cell Line , Cell Proliferation , Centrosome/metabolism , Mice , Signal Transduction , Transcription Factors , Tumor Suppressor Proteins/metabolism
14.
Cell Death Dis ; 10(10): 736, 2019 09 30.
Article in English | MEDLINE | ID: mdl-31570693

ABSTRACT

Complex molecular cross talk between stromal cells and the leukemic cells in bone marrow is known to contribute significantly towards drug-resistance. Here, we have identified the molecular events that lead to stromal cells mediated therapy-resistance in acute myeloid leukemia (AML). Our work demonstrates that stromal cells downregulate miR-23a-5p levels in leukemic cells to protect them from the chemotherapy induced apoptosis. Downregulation of miR-23a-5p in leukemic cells leads to upregulation of protective autophagy by targeting TLR2 expression. Further, autophagy inhibitors when used as adjuvants along with conventional drugs can improve drug sensitivity in vitro as well in vivo in a mouse model of leukemia. Our work also demonstrates that this mechanism of bone marrow stromal cell mediated regulation of miR-23a-5p levels and subsequent molecular events are relevant predominantly in myeloid leukemia. Our results illustrate the critical and dynamic role of the bone marrow microenvironment in modulating miRNA expression in leukemic cells which could contribute significantly to drug resistance and subsequent relapse, possibly through persistence of minimal residual disease in this environment.


Subject(s)
Autophagy/genetics , Leukemia, Myeloid, Acute/genetics , MicroRNAs/genetics , Stromal Cells/drug effects , Toll-Like Receptor 2/drug effects , Animals , Apoptosis/drug effects , Autophagy/drug effects , Bone Marrow Cells/drug effects , Daunorubicin/pharmacology , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/pathology , Male , Mice , Neoplasm, Residual/genetics , Neoplasm, Residual/pathology , Stromal Cells/pathology , Tumor Microenvironment/drug effects , Xenograft Model Antitumor Assays
15.
Trends Cell Biol ; 28(2): 157-170, 2018 02.
Article in English | MEDLINE | ID: mdl-29132729

ABSTRACT

Morphogens are signaling molecules produced by a localized source, specifying cell fate in a graded manner. The source secretes morphogens into the extracellular milieu to activate various target genes in an autocrine or paracrine manner. Here we describe various secreted forms of two canonical morphogens, the lipid-anchored Hedgehog (Hh) and Wnts, indicating the involvement of multiple carriers in the transport of these morphogens. These different extracellular secreted forms are likely to have distinct functions. Here we evaluate newly identified mechanisms that morphogens use to traverse the required distance to activate discrete paracrine signaling.


Subject(s)
Hedgehog Proteins/metabolism , Lipid Metabolism/physiology , Morphogenesis/physiology , Wnt Proteins/metabolism , Animals , Drosophila Proteins/metabolism , Humans
16.
Indian J Dent Res ; 28(4): 388-394, 2017.
Article in English | MEDLINE | ID: mdl-28836529

ABSTRACT

BACKGROUND: Osteoporosis and periodontitis have several risk factors in common. The majority of studies evaluating periodontal bone loss and systemic bone mineral density have found that low bone mineral density systemically is significantly associated with an increase in loss of alveolar bone height and periodontal destruction. Hence, the purpose of the study was to determine the effect of periodontitis on mandibular radiomorphometric indices, serum calcium and serum estradiol levels in postmenopausal women. MATERIALS AND METHODS: Forty female patients in the age group of 35-55 years were included in the study. The participants were divided into two equal groups, i.e., control group A (twenty - postmenopausal women with healthy periodontium) and study group B (twenty - postmenopausal women with periodontitis). A thorough clinical examination of all the forty patients was carried out to detect the presence of periodontitis on the basis of clinical attachment level. Quantitative indices were measured on digital panoramic radiographs, and serum calcium and estradiol levels were estimated. RESULTS: No statistically significant correlation of periodontitis with any of the radiomorphometric indices, serum calcium and serum estradiol levels was observed in postmenopausal women. CONCLUSION: There is little evidence of correlation of serum estradiol, serum calcium levels, and morphometric indices with periodontitis and therefore detailed further research about this correlation is required.


Subject(s)
Calcium/blood , Estradiol/blood , Mandible/diagnostic imaging , Periodontitis/blood , Periodontitis/diagnostic imaging , Postmenopause/blood , Adult , Case-Control Studies , Female , Humans , Middle Aged
17.
Contemp Clin Dent ; 8(1): 53-58, 2017.
Article in English | MEDLINE | ID: mdl-28566852

ABSTRACT

BACKGROUND: Osteoporosis is a disease that is seen commonly with increasing age. The purpose of this study was to compare the bone quality of pre- and post-menopausal women using the quantitative indices determined by measurements on panoramic radiographs (mental index, inferior and superior panoramic mandibular indices, antegonion index [AGI], and gonion index) and to determine the effects of serum calcium and serum estradiol levels on alveolar bone loss. MATERIALS AND METHODS: Sixty female patients in the age group of 25-55 years were included in the study. The patients were divided into three equal groups, i.e., control Group A (twenty - premenopausal women), study Group B (twenty - postmenopausal women with healthy periodontium), study Group C (twenty - postmenopausal women with periodontitis). Quantitative indices were measured on digital panoramic radiographs of the patients and serum calcium and estradiol levels were determined. RESULTS: Correlation of serum calcium with radiomorphometric indices of all the groups showed statistically nonsignificant differences. On correlating mean estradiol levels with radiographic indices of patients of Group A and Group B showed statistically nonsignificant differences. On correlating mean estradiol levels with radiographic indices of patients of Group C patients showed statistically significant difference with positive correlation with cortical width (P = 0.04) and AGI (P = 0.02) while statistically nonsignificant correlation with other indices. The statistical tests used for the analysis of the result were one-way ANOVA, multiple comparison Tukey test, Chi-square test, Student's t-test. CONCLUSION: There is a little evidence of correlation of these indices with serum estradiol and calcium levels, and therefore, detailed further research about this correlation is required.

18.
Cell Mol Life Sci ; 74(9): 1567-1576, 2017 05.
Article in English | MEDLINE | ID: mdl-27826642

ABSTRACT

Intercellular communications play a vital role during tissue patterning, tissue repair, and immune reactions, in homeostasis as well as in disease. Exosomes are cell-derived secreted vesicles, extensively studied for their role in intercellular communication. Exosomes have the intrinsic ability to package multiple classes of proteins and nucleic acids within their lumens and on their membranes. Here, we explore the hypothesis that exosomal targeting may represent a cellular strategy that has evolved to deliver specific combinations of signals to specific target cells and influence normal or pathological processes. This review aims to evaluate the available evidence for this hypothesis and to identify open questions whose answers will illuminate our understanding and applications of exosome biology.


Subject(s)
Cell Membrane/metabolism , Exosomes/metabolism , Signal Transduction , Animals , Cell Communication , Humans , Models, Biological , RNA/metabolism
19.
Pediatrics ; 137(4)2016 Apr.
Article in English | MEDLINE | ID: mdl-26993128

ABSTRACT

Immobility-induced hypercalcemia is a rare cause of hypercalcemia in children, and to our knowledge it has never been reported in an infant. Infants and children are in a state of high bone turnover. Therefore, they are prone to the imbalance of osteoblastic and osteoclastic activity that occurs with prolonged immobilization, leading to hypercalcemia. Here we present the case of an infant with hypercalcemia who presented with fatigue, irritability, and failure to thrive after prolonged immobilization. Therapeutic interventions were conservative and included hydration and increased mobility leading to complete resolution. This case highlights the importance of including this rare entity in a differential diagnosis of hypercalcemia as well as screening postsurgical patients with prolonged immobility for hypercalcemia.


Subject(s)
Hypercalcemia/diagnosis , Hypercalcemia/etiology , Immobilization/adverse effects , Diagnosis, Differential , Female , Humans , Hypercalcemia/blood , Immobilization/methods , Infant
20.
Mol Biol Cell ; 26(25): 4700-17, 2015 Dec 15.
Article in English | MEDLINE | ID: mdl-26490120

ABSTRACT

Hedgehog (Hh) is a secreted morphogen involved in both short- and long-range signaling necessary for tissue patterning during development. It is unclear how this dually lipidated protein is transported over a long range in the aqueous milieu of interstitial spaces. We previously showed that the long-range signaling of Hh requires its oligomerization. Here we show that Hh is secreted in the form of exovesicles. These are derived by the endocytic delivery of cell surface Hh to multivesicular bodies (MVBs) via an endosomal sorting complex required for transport (ECSRT)-dependent process. Perturbations of ESCRT proteins have a selective effect on long-range Hh signaling in Drosophila wing imaginal discs. Of importance, oligomerization-defective Hh is inefficiently incorporated into exovesicles due to its poor endocytic delivery to MVBs. These results provide evidence that nanoscale organization of Hh regulates the secretion of Hh on ESCRT-derived exovesicles, which in turn act as a vehicle for long-range signaling.


Subject(s)
Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Endocytosis/genetics , Endosomal Sorting Complexes Required for Transport/genetics , Hedgehog Proteins/genetics , Animals , Drosophila Proteins/metabolism , Drosophila melanogaster/growth & development , Endosomal Sorting Complexes Required for Transport/metabolism , Hedgehog Proteins/metabolism , Imaginal Discs/growth & development , Imaginal Discs/metabolism , Metabolic Networks and Pathways/genetics , Multivesicular Bodies/genetics , Multivesicular Bodies/metabolism , Protein Transport/genetics , Wings, Animal/growth & development , Wings, Animal/metabolism
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