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1.
Proc Natl Acad Sci U S A ; 120(29): e2301002120, 2023 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-37428930

RESUMEN

Autophagy is a major means for the elimination of protein inclusions in neurons in neurodegenerative diseases such as Parkinson's disease (PD). Yet, the mechanism of autophagy in the other brain cell type, glia, is less well characterized and remains largely unknown. Here, we present evidence that the PD risk factor, Cyclin-G-associated kinase (GAK)/Drosophila homolog Auxilin (dAux), is a component in glial autophagy. The lack of GAK/dAux increases the autophagosome number and size in adult fly glia and mouse microglia, and generally up-regulates levels of components in the initiation and PI3K class III complexes. GAK/dAux interacts with the master initiation regulator UNC-51like autophagy activating kinase 1/Atg1 via its uncoating domain and regulates the trafficking of Atg1 and Atg9 to autophagosomes, hence controlling the onset of glial autophagy. On the other hand, lack of GAK/dAux impairs the autophagic flux and blocks substrate degradation, suggesting that GAK/dAux might play additional roles. Importantly, dAux contributes to PD-like symptoms including dopaminergic neurodegeneration and locomotor function in flies. Our findings identify an autophagy factor in glia; considering the pivotal role of glia under pathological conditions, targeting glial autophagy is potentially a therapeutic strategy for PD.


Asunto(s)
Proteínas de Drosophila , Enfermedad de Parkinson , Animales , Ratones , Drosophila/metabolismo , Auxilinas/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Autofagia , Ciclinas/metabolismo , Neuroglía/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas Relacionadas con la Autofagia/metabolismo , Proteínas de la Membrana/metabolismo
2.
Traffic ; 23(10): 506-520, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36053864

RESUMEN

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of familial and sporadic Parkinson's disease. A plethora of evidence has indicated a role for LRRK2 in endolysosomal trafficking in neurons, while LRRK2 function in glia, although highly expressed, remains largely unknown. Here, we present evidence that LRRK2/dLRRK mediates a lysosomal pathway that contributes to glial cell death and the survival of dopaminergic (DA) neurons. LRRK2/dLRRK knockdown in the immortalized microglia or flies results in enlarged and swelling lysosomes fewer in number. These lysosomes are less mobile, wrongly acidified, exhibit defective membrane permeability and reduced activity of the lysosome hydrolase cathepsin B. In addition, LRRK2/dLRRK depletion causes glial apoptosis, DA neurodegeneration, and locomotor deficits in an age-dependent manner. Taken together, these findings demonstrate a functional role of LRRK2/dLRRK in regulating the glial lysosomal pathway; deficits in lysosomal biogenesis and function linking to glial apoptosis potentially underlie the mechanism of DA neurodegeneration, providing insights on LRRK2/dLRRK function in normal and pathological brains.


Asunto(s)
Catepsina B , Neuronas Dopaminérgicas , Catepsina B/genética , Catepsina B/metabolismo , Muerte Celular , Neuronas Dopaminérgicas/metabolismo , Leucina/genética , Leucina/metabolismo , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/metabolismo , Lisosomas/metabolismo , Mutación , Neuroglía/metabolismo
3.
BMC Genomics ; 25(1): 80, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243165

RESUMEN

BACKGROUND: Hemocytes are immune cells that patrol the mosquito hemocoel and mediate critical cellular defense responses against pathogens. However, despite their importance, a comprehensive transcriptome of these cells was lacking because they constitute a very small fraction of the total cells in the insect, limiting the study of hemocyte differentiation and immune function. RESULTS: In this study, an in-depth hemocyte transcriptome was built by extensive bulk RNA sequencing and assembly of hemocyte RNAs from adult A. gambiae female mosquitoes, based on approximately 2.4 billion short Illumina and about 9.4 million long PacBio high-quality reads that mapped to the A. gambiae PEST genome (P4.14 version). A total of 34,939 transcripts were annotated including 4,020 transcripts from novel genes and 20,008 novel isoforms that result from extensive differential splicing of transcripts from previously annotated genes. Most hemocyte transcripts identified (89.8%) are protein-coding while 10.2% are non-coding RNAs. The number of transcripts identified in the novel hemocyte transcriptome is twice the number in the current annotation of the A. gambiae genome (P4.14 version). Furthermore, we were able to refine the analysis of a previously published single-cell transcriptome (scRNAseq) data set by using the novel hemocyte transcriptome as a reference to re-define the hemocyte clusters and determine the path of hemocyte differentiation. Unsupervised pseudo-temporal ordering using the Tools for Single Cell Analysis software uncovered a novel putative prohemocyte precursor cell type that gives rise to prohemocytes. Pseudo-temporal ordering with the Monocle 3 software, which analyses changes in gene expression during dynamic biological processes, determined that oenocytoids derive from prohemocytes, a cell population that also gives rise to the granulocyte lineage. CONCLUSION: A high number of mRNA splice variants are expressed in hemocytes, and they may account for the plasticity required to mount efficient responses to many different pathogens. This study highlights the importance of a comprehensive set of reference transcripts to perform robust single-cell transcriptomic data analysis of cells present in low abundance. The detailed annotation of the hemocyte transcriptome will uncover new facets of hemocyte development and function in adult dipterans and is a valuable community resource for future studies on mosquito cellular immunity.


Asunto(s)
Anopheles , Animales , Femenino , Anopheles/genética , Anopheles/metabolismo , Hemocitos , Perfilación de la Expresión Génica , Transcriptoma , Proteínas/metabolismo
4.
J Pediatr ; 273: 113913, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38218371

RESUMEN

OBJECTIVE: To assess the rate and risk factors for reactivation of retinopathy of prematurity (ROP) after intravitreal injection (IVI) of antivascular endothelial growth factor (VEGF) agents. STUDY DESIGN: Infants who received IVI therapy between 2017 and 2022 were enrolled and divided into 2 groups: those with and without ROP reactivation. Information on ROP variables and patient variables were analyzed using multivariable logistic regression. RESULTS: A total of 114 infants with 223 eyes were enrolled in the study. The ROP reactivation rate was 11.4% of infants (9.9% of eyes). The mean duration of reactivation was 84 ± 45 days. Among the 223 eyes treated with IVI, reactivation rates were 6% for bevacizumab, 13.9% for aflibercept, and 22.2% for ranibizumab. A multivariable regression model showed that ranibizumab was an independent risk factor (OR 11.4, P = .008) for reactivation. Other risk factors included infants with periventricular leukomalacia (OR 13.8, P = .003), patent ductus arteriosus ligation (OR 10.7, P = .032), and infants who still required invasive mechanical ventilation on the day of IVI therapy (OR 7.0, P = .018). CONCLUSIONS: All anti-VEGF agents carry a risk of ROP reactivation, with the risk being greater with ranibizumab 0.25 mg than with bevacizumab 0.625 mg. Reactivation of ROP should be assessed vigilantly, especially in those infants with increased risks. Future research to determine the optimal anti-VEGF selection and dosage in high-risk infants is warranted.

5.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34078666

RESUMEN

Intrinsic mechanisms such as temporal series of transcription factors orchestrate neurogenesis from a limited number of neural progenitors in the brain. Extrinsic regulations, however, remain largely unexplored. Here we describe a two-step glia-derived signal that regulates neurogenesis in the Drosophila mushroom body (MB). In a temporal manner, glial-specific ubiquitin ligase dSmurf activates non-cell-autonomous Hedgehog signaling propagation by targeting the receptor Patched to suppress and promote the exit of MB neuroblast (NB) proliferation, thereby specifying the correct α/ß cell number without affecting differentiation. Independent of NB proliferation, dSmurf also stabilizes the expression of the cell-adhesion molecule Fasciclin II (FasII) via its WW domains and regulates FasII homophilic interaction between glia and MB axons to refine α/ß-lobe integrity. Our findings provide insights into how extrinsic glia-to-neuron communication coordinates with NB proliferation capacity to regulate MB neurogenesis; glial proteostasis is likely a generalized mechanism in orchestrating neurogenesis.


Asunto(s)
Comunicación Celular , Proliferación Celular , Cuerpos Pedunculados/embriología , Neurogénesis , Neuroglía/metabolismo , Animales , Proteínas de Drosophila/metabolismo , Drosophila melanogaster
6.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36499080

RESUMEN

Parkinson's disease (PD) is a progressive neurodegenerative disorder. The classical behavioral defects of PD patients involve motor symptoms such as bradykinesia, tremor, and rigidity, as well as non-motor symptoms such as anosmia, depression, and cognitive impairment. Pathologically, the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN) and the accumulation of α-synuclein (α-syn)-composed Lewy bodies (LBs) and Lewy neurites (LNs) are key hallmarks. Glia are more than mere bystanders that simply support neurons, they actively contribute to almost every aspect of neuronal development and function; glial dysregulation has been implicated in a series of neurodegenerative diseases including PD. Importantly, amounting evidence has added glial activation and neuroinflammation as new features of PD onset and progression. Thus, gaining a better understanding of glia, especially neuron-glia crosstalk, will not only provide insight into brain physiology events but also advance our knowledge of PD pathologies. This review addresses the current understanding of α-syn pathogenesis in PD, with a focus on neuron-glia crosstalk. Particularly, the transmission of α-syn between neurons and glia, α-syn-induced glial activation, and feedbacks of glial activation on DA neuron degeneration are thoroughly discussed. In addition, α-syn aggregation, iron deposition, and glial activation in regulating DA neuron ferroptosis in PD are covered. Lastly, we summarize the preclinical and clinical therapies, especially targeting glia, in PD treatments.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Enfermedad de Parkinson/patología , Cuerpos de Lewy/metabolismo , Sustancia Negra/metabolismo , Neuronas Dopaminérgicas/metabolismo , Degeneración Nerviosa/patología
7.
Yi Chuan ; 44(4): 300-312, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35437238

RESUMEN

The animal central nervous system is composed of neurons and neuroglia (glia). Extensive research on neurons have shown that they are the major cells to transduce signals in mediating neural development and function, and the glial cells mainly play a role in supporting neurons and maintaining their normal function. Nonetheless, emerging evidence has indicated that glial cells exhibit active roles in virtually all aspects of neuronal function and development. Research using the model organism Drosophila melanogaster reveals that glial cells are key players in the regulation of neural development, nutritional metabolism, sleep, longevity, apoptosis, courtship, smell, learning and memory and other physiological behaviors. In this review, we summarize the research progress of glial cells in regulating different physiological activities in Drosophila, in hope of providing insights on the mechanisms and new prospects on future glial research.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Animales , Drosophila , Proteínas de Drosophila/metabolismo , Neuroglía/fisiología , Neuronas/metabolismo
8.
Cancer ; 127(22): 4161-4170, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34293201

RESUMEN

BACKGROUND: The use of external-beam radiotherapy for locally advanced nonanaplastic thyroid cancer remains controversial. This prospective study evaluated the efficacy and tolerability of intensity-modulated radiation therapy (IMRT) with or without concurrent chemotherapy in patients with locally advanced thyroid cancer. METHODS: The authors conducted a nonrandomized phase 2 trial of IMRT with or without concurrent doxorubicin in patients with gross residual or unresectable nonanaplastic thyroid carcinoma (ClinicalTrials.gov identifier NCT01882816). The primary end point was 2-year locoregional progression-free survival (PFS). Secondary end points included overall survival (OS), safety, patient-reported outcomes, and functional outcomes. RESULTS: Twenty-seven patients were enrolled: 12 (44.4%) with unresectable disease and 15 (55.6%) with gross residual disease. The median follow-up was 45.6 months (interquartile range, 42.0-51.6 months); the 2-year cumulative incidences of locoregional PFS and OS were 79.7% and 77.3%, respectively. The rate of grade 3 or higher acute and late toxicities was 33.4%. There were no significant functional differences 12 months after treatment (assessed objectively by the modified barium swallow study). Patient-reported quality of life in the experimental group was initially lower but returned to the baseline after 6 months and improved thereafter. In a post hoc analysis, concurrent chemotherapy with intensity-modulated radiation therapy (CC-IMRT) resulted in significantly less locoregional failure at 2 years (no failure vs 50%; P = .001), with higher rates of grade 2 or higher acute dermatitis, mucositis, and dysphagia but no difference in long-term toxicity, functionality, or patient-reported quality of life. CONCLUSIONS: In light of the excellent locoregional control rates achieved with CC-IMRT and its acceptable toxicity profile as confirmed by functional assessments and patient-reported outcomes, CC-IMRT may be preferred over IMRT alone.


Asunto(s)
Radioterapia de Intensidad Modulada , Neoplasias de la Tiroides , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Doxorrubicina/efectos adversos , Humanos , Estudios Prospectivos , Calidad de Vida , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Neoplasias de la Tiroides/tratamiento farmacológico , Neoplasias de la Tiroides/etiología , Neoplasias de la Tiroides/radioterapia
9.
BMC Fam Pract ; 22(1): 145, 2021 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-34217212

RESUMEN

BACKGROUND: The rising prevalence of non-communicable diseases (NCDs) such as diabetes mellitus (DM) and hypertension (HT) has placed a tremendous burden on healthcare systems around the world, resulting in a call for more effective service delivery models. Better continuity of care (CoC) has been associated with improved health outcomes. This review examines the association between CoC and health outcomes in patients with DM and/or HT. METHODS: This was a systematic review with searches carried out on 13 March 2021 through PubMed, Embase, MEDLINE and CINAHL plus, clinical trials registry and bibliography reviews. Eligibility criteria were: published in English; from 2000 onwards; included adult DM and/or HT patients; examined CoC as their main intervention/exposure; and utilised quantifiable outcome measures (categorised into health indicators and service utilisation). The study quality was evaluated with Critical Appraisal Skills Programme (CASP) appraisal checklists. RESULTS: Initial searching yielded 21,090 results with 42 studies meeting the inclusion criteria. High CoC was associated with reduced hospitalisation (16 out of 18 studies), emergency room attendances (eight out of eight), mortality rate (six out of seven), disease-related complications (seven out of seven), and healthcare expenses (four out of four) but not with blood pressure (two out of 13), lipid profile (one out of six), body mass index (zero out of three). Six out of 12 studies on diabetic outcomes reported significant improvement in haemoglobin A1c by higher CoC. Variations in the classification of continuity of care and outcome definition were identified, making meta-analyses inappropriate. CASP evaluation rated most studies fair in quality, but found insufficient adjustment on confounders, selection bias and short follow-up period were common limitations of current literatures. CONCLUSION: There is evidence of a strong association between higher continuity of care and reduced mortality rate, complication risks and health service utilisation among DM and/or HT patients but little to no improvement in various health indicators. Significant methodological heterogeneity in how CoC and patient outcomes are assessed limits the ability for meta-analysis of findings. Further studies comprising sufficient confounding adjustment and standardised definitions are needed to provide stronger evidence of the benefits of CoC on patients with DM and/or HT.


Asunto(s)
Diabetes Mellitus , Hipertensión , Adulto , Continuidad de la Atención al Paciente , Diabetes Mellitus/epidemiología , Diabetes Mellitus/terapia , Servicios de Salud , Humanos , Hipertensión/epidemiología , Hipertensión/terapia , Evaluación de Resultado en la Atención de Salud
10.
Genome Res ; 27(12): 2108-2119, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29074739

RESUMEN

Deep sequencing of size-selected DNase I-treated chromatin (DNase-seq) allows high-resolution measurement of chromatin accessibility to DNase I cleavage, permitting identification of de novo active cis-regulatory modules (CRMs) and individual transcription factor (TF) binding sites. We adapted DNase-seq to nuclei isolated from C. elegans embryos and L1 arrest larvae to generate high-resolution maps of TF binding. Over half of embryonic DNase I hypersensitive sites (DHSs) were annotated as noncoding, with 24% in intergenic, 12% in promoters, and 28% in introns, with similar statistics observed in L1 arrest larvae. Noncoding DHSs are highly conserved and enriched in marks of enhancer activity and transcription. We validated noncoding DHSs against known enhancers from myo-2, myo-3, hlh-1, elt-2, and lin-26/lir-1 and recapitulated 15 of 17 known enhancers. We then mined DNase-seq data to identify putative active CRMs and TF footprints. Using DNase-seq data improved predictions of tissue-specific expression compared with motifs alone. In a pilot functional test, 10 of 15 DHSs from pha-4, icl-1, and ceh-13 drove reporter gene expression in transgenic C. elegans Overall, we provide experimental annotation of 26,644 putative CRMs in the embryo containing 55,890 TF footprints, as well as 15,841 putative CRMs in the L1 arrest larvae containing 32,685 TF footprints.


Asunto(s)
Caenorhabditis elegans/genética , Cromatina/metabolismo , Regulación de la Expresión Génica , Genoma de los Helmintos , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/metabolismo , Animales , Animales Modificados Genéticamente , Sitios de Unión , Caenorhabditis elegans/embriología , Secuencia Conservada , ADN de Helmintos , Desoxirribonucleasa I/metabolismo , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Proteínas del Helminto/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Unión Proteica
11.
BMC Biotechnol ; 20(1): 39, 2020 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-32711499

RESUMEN

BACKGROUND: With the high demand for diesel across the world, environmental decontamination from its improper usage, storage and accidental spills becomes necessary. One highly environmentally friendly and cost-effective decontamination method is to utilize diesel-degrading microbes as a means for bioremediation. Here, we present a newly isolated and identified strain of Acinetobacter calcoaceticus ('CA16') as a candidate for the bioremediation of diesel-contaminated areas. RESULTS: Acinetobacter calcoaceticus CA16 was able to survive and grow in minimal medium with diesel as the only source of carbon. We determined through metabolomics that A. calcoaceticus CA16 appears to be efficient at diesel degradation. Specifically, CA16 is able to degrade 82 to 92% of aliphatic alkane hydrocarbons (CnHn + 2; where n = 12-18) in 28 days. Several diesel-degrading genes (such as alkM and xcpR) that are present in other microbes were also found to be activated in CA16. CONCLUSIONS: The results presented here suggest that Acinetobacter strain CA16 has good potential in the bioremediation of diesel-polluted environments.


Asunto(s)
Acinetobacter calcoaceticus/genética , Acinetobacter calcoaceticus/aislamiento & purificación , Acinetobacter calcoaceticus/metabolismo , Gasolina , Genómica , Microbiología del Suelo , Acinetobacter calcoaceticus/clasificación , Alcanos , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodegradación Ambiental , Canadá , Carbono/metabolismo , Regulación Bacteriana de la Expresión Génica , Hidrocarburos , Metabolómica , Filogenia , Suelo
12.
Development ; 144(8): 1510-1517, 2017 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-28242614

RESUMEN

The Drosophila larval central nervous system comprises the central brain, ventral nerve cord and optic lobe. In these regions, neuroblasts (NBs) divide asymmetrically to self-renew and generate differentiated neurons or glia. To date, mechanisms of preventing neuron dedifferentiation are still unclear, especially in the optic lobe. Here, we show that the zinc-finger transcription factor Nerfin-1 is expressed in early-stage medulla neurons and is essential for maintaining their differentiation. Loss of Nerfin-1 activates Notch signaling, which promotes neuron-to-NB reversion. Repressing Notch signaling largely rescues dedifferentiation in nerfin-1 mutant clones. Thus, we conclude that Nerfin-1 represses Notch activity in medulla neurons and prevents them from dedifferentiation.


Asunto(s)
Diferenciación Celular , Proteínas de Drosophila/antagonistas & inhibidores , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citología , Drosophila melanogaster/metabolismo , Bulbo Raquídeo/citología , Neuronas/citología , Neuronas/metabolismo , Receptores Notch/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Animales , Carcinogénesis/patología , Desdiferenciación Celular , Técnicas de Silenciamiento del Gen , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Lóbulo Óptico de Animales no Mamíferos/anatomía & histología , Lóbulo Óptico de Animales no Mamíferos/citología , Receptores Notch/metabolismo , Transducción de Señal , Regulación hacia Arriba , Dedos de Zinc
13.
J Biol Chem ; 293(44): 17119-17134, 2018 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-30209132

RESUMEN

The Hippo signaling pathway is known to play an important role in multiple physiological processes, including adipogenesis. However, whether the downstream components of the Hippo pathway are involved in adipogenesis remains unknown. Here we demonstrate that the TEA domain family (TEAD) transcription factors are essential for adipogenesis in murine 3T3-L1 preadipocytes. Knockdown of TEAD1-4 stimulated adipogenesis and increased the expression of adipocyte markers in these cells. Interestingly, we found that the TEAD4 knockdown-mediated adipogenesis proceeded in a Yes-associated protein (YAP)/TAZ (Wwtr1)-independent manner and that adipogenesis suppression in WT cells involved formation of a ternary complex comprising TEAD4 and the transcriptional cofactors C-terminal binding protein 2 (CtBP2) and vestigial-like family member 4 (VGLL4). VGLL4 acted as an adaptor protein that enhanced the interaction between TEAD4 and CtBP2, and this TEAD4-VGLL4-CtBP2 ternary complex dynamically existed at the early stage of adipogenesis. Finally, we verified that TEAD4 directly targets the promoters of major adipogenesis transcription factors such as peroxisome proliferator-activated receptor γ (PPARγ) and adiponectin, C1Q, and collagen domain-containing (Adipoq) during adipogenesis. These findings reveal critical insights into the role of the TEAD4-VGLL4-CtBP2 transcriptional repressor complex in suppression of adipogenesis in murine preadipocytes.


Asunto(s)
Adipocitos/metabolismo , Adipogénesis , Proteínas de Unión al ADN/metabolismo , Proteínas Musculares/metabolismo , Fosfoproteínas/metabolismo , Factores de Transcripción/metabolismo , Células 3T3-L1 , Adipocitos/citología , Oxidorreductasas de Alcohol , Animales , Proteínas Co-Represoras , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica , Humanos , Ratones , Proteínas Musculares/genética , PPAR gamma/genética , PPAR gamma/metabolismo , Fosfoproteínas/genética , Unión Proteica , Factores de Transcripción de Dominio TEA , Factores de Transcripción/genética , Activación Transcripcional
14.
BMC Microbiol ; 19(1): 5, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30621587

RESUMEN

BACKGROUND: Bacillus velezensis is an endospore-forming, free-living soil bacterium with potential as a biopesticide against a broad spectrum of microbial pathogens of plants. Its potential for commercial development is enhanced by rapid replication and resistance to adverse environmental conditions, typical of Bacillus species. However, the use of beneficial microbes against phytopathogens has not gained dominance due to limitations that may be overcome with new biopesticidal strains and/or new biological knowledge. RESULTS: Here, we isolated B. velezensis strain 9D-6 and showed that it inhibits the in vitro growth of prokaryotic and eukaryotic pathogens, including the bacteria Bacillus cereus , Clavibacter michiganensis, Pantoea agglomerans, Ralstonia solanacearum, Xanthomonas campestris, and Xanthomonas euvesicatoria; and the fungi Alternaria solani, Cochliobolus carbonum, Fusarium oxysporum, Fusarium solani, Gibberella pulicaris, Gibberella zeae, Monilinia fructicola, Pyrenochaeta terrestris and Rhizoctonia solani. Antimicrobial compounds with activity against Clavibacter michiganensis were isolated from B. velezensis 9D-6 and characterized by high resolution LC-MS/MS, yielding formulae of C52H91N7O13 and C53H93N7O13, which correspond to [Leu7] surfactins C14 and C15 (also called surfactin B and surfactin C), respectively. We further sequenced the B. velezensis 9D-6 genome which consists of a single circular chromosome and revealed 13 gene clusters expected to participate in antimicrobial metabolite production, including surfactin and two metabolites that have not typically been found in this species - ladderane and lantipeptide. Despite being unable to inhibit the growth of Pseudomonas syringae DC3000 in an in vitro plate assay, B. velezensis 9D-6 significantly reduced root colonization by DC3000, suggesting that 9D-6 uses methods other than antimicrobials to control phytopathogens in the environment. Finally, using in silico DNA-DNA hybridization (isDDH), we confirm previous findings that many strains currently classified as B. amyloliquefaciens are actually B. velezensis. CONCLUSIONS: The data presented here suggest B. velezensis 9D-6 as a candidate plant growth promoting bacterium (PGPB) and biopesticide, which uses a unique complement of antimicrobials, as well as other mechanisms, to protect plants against phytopathogens. Our results may contribute to future utilization of this strain, and will contribute to a knowledge base that will help to advance the field of microbial biocontrol.


Asunto(s)
Bacillus/genética , Genoma Bacteriano , Interacciones Microbianas , Antiinfecciosos/metabolismo , Bacterias/crecimiento & desarrollo , Hongos/crecimiento & desarrollo , Lipopéptidos/genética , Lipopéptidos/metabolismo , Péptidos Cíclicos/genética , Péptidos Cíclicos/metabolismo
15.
Clin Proteomics ; 16: 43, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31889940

RESUMEN

BACKGROUND: There is a need to demonstrate a proof of principle that proteomics has the capacity to analyze plasma from breast cancer versus other diseases and controls in a multisite clinical trial design. The peptides or proteins that show a high observation frequency, and/or precursor intensity, specific to breast cancer plasma might be discovered by comparison to other diseases and matched controls. The endogenous tryptic peptides of breast cancer plasma were compared to ovarian cancer, female normal, sepsis, heart attack, Alzheimer's and multiple sclerosis along with the institution-matched normal and control samples collected directly onto ice. METHODS: Endogenous tryptic peptides were extracted from individual breast cancer and control EDTA plasma samples in a step gradient of acetonitrile, and collected over preparative C18 for LC-ESI-MS/MS with a set of LTQ XL linear quadrupole ion traps working together in parallel to randomly and independently sample clinical populations. The MS/MS spectra were fit to fully tryptic peptides or phosphopeptides within proteins using the X!TANDEM algorithm. The protein observation frequency was counted using the SEQUEST algorithm after selecting the single best charge state and peptide sequence for each MS/MS spectra. The observation frequency was subsequently tested by Chi Square analysis. The log10 precursor intensity was compared by ANOVA in the R statistical system. RESULTS: Peptides and/or phosphopeptides of common plasma proteins such as APOE, C4A, C4B, C3, APOA1, APOC2, APOC4, ITIH3 and ITIH4 showed increased observation frequency and/or precursor intensity in breast cancer. Many cellular proteins also showed large changes in frequency by Chi Square (χ2 > 100, p < 0.0001) in the breast cancer samples such as CPEB1, LTBP4, HIF-1A, IGHE, RAB44, NEFM, C19orf82, SLC35B1, 1D12A, C8orf34, HIF1A, OCLN, EYA1, HLA-DRB1, LARS, PTPDC1, WWC1, ZNF562, PTMA, MGAT1, NDUFA1, NOGOC, OR1E1, OR1E2, CFI, HSA12, GCSH, ELTD1, TBX15, NR2C2, FLJ00045, PDLIM1, GALNT9, ASH2L, PPFIBP1, LRRC4B, SLCO3A1, BHMT2, CS, FAM188B2, LGALS7, SAT2, SFRS8, SLC22A12, WNT9B, SLC2A4, ZNF101, WT1, CCDC47, ERLIN1, SPFH1, EID2, THOC1, DDX47, MREG, PTPRE, EMILIN1, DKFZp779G1236 and MAP3K8 among others. The protein gene symbols with large Chi Square values were significantly enriched in proteins that showed a complex set of previously established functional and structural relationships by STRING analysis. An increase in mean precursor intensity of peptides was observed for QSER1 as well as SLC35B1, IQCJ-SCHIP1, MREG, BHMT2, LGALS7, THOC1, ANXA4, DHDDS, SAT2, PTMA and FYCO1 among others. In contrast, the QSER1 peptide QPKVKAEPPPK was apparently specific to ovarian cancer. CONCLUSION: There was striking agreement between the breast cancer plasma peptides and proteins discovered by LC-ESI-MS/MS with previous biomarkers from tumors, cells lines or body fluids by genetic or biochemical methods. The results indicate that variation in plasma peptides from breast cancer versus ovarian cancer may be directly discovered by LC-ESI-MS/MS that will be a powerful tool for clinical research. It may be possible to use a battery of sensitive and robust linear quadrupole ion traps for random and independent sampling of plasma from a multisite clinical trial.

16.
Adv Exp Med Biol ; 1175: 335-353, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31583594

RESUMEN

Microglia are the most abundant immune cells in the central nervous system (CNS), where they interact with neurons and exhibit a wide array of functions in physiological and pathological conditions. Physiologically, microglia mediate synaptic pruning and remodeling crucial for neural circuits and brain connectivity. In pathological conditions such as neurodegeneration in the Parkinson's disease (PD), microglia are activated, migrated to the injury site, and prone to engulf debris, sense pathology, and secrete possible pro- and anti-inflammatory factors. Microglia mediate responses such as inflammation and phagocytosis associated with neurodegeneration and are pivotal players in exacerbating or relieving disease progression. This chapter provides an overview on microglial function in the neurodegenerative disease-Parkinson's disease (PD). An overview on the pathology of PD will first be given, followed by discussion on receptors and signaling pathways involved in microglia-mediated inflammation and phagocytosis. Mechanism of how microglia contribute to PD by inflammation, phagocytosis of α-Synuclein (α-Syn), and interaction with PD genes will also be discussed.


Asunto(s)
Microglía/citología , Enfermedad de Parkinson/fisiopatología , Humanos , Inflamación/fisiopatología , Fagocitosis , Transducción de Señal , alfa-Sinucleína
17.
Adv Exp Med Biol ; 1175: 15-44, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31583583

RESUMEN

As the nervous system evolved from the diffused to centralised form, the neurones were joined by the appearance of the supportive cells, the neuroglia. Arguably, these non-neuronal cells evolve into a more diversified cell family than the neurones are. The first ancestral neuroglia appeared in flatworms being mesenchymal in origin. In the nematode C. elegans proto-astrocytes/supportive glia of ectodermal origin emerged, albeit the ensheathment of axons by glial cells occurred later in prawns. The multilayered myelin occurred by convergent evolution of oligodendrocytes and Schwann cells in vertebrates above the jawless fishes. Nutritive partitioning of the brain from the rest of the body appeared in insects when the hemolymph-brain barrier, a predecessor of the blood-brain barrier was formed. The defensive cellular mechanism required specialisation of bona fide immune cells, microglia, a process that occurred in the nervous system of leeches, bivalves, snails, insects and above. In ascending phylogeny, new type of glial cells, such as scaffolding radial glia, appeared and as the bran sizes enlarged, the glia to neurone ratio increased. Humans possess some unique glial cells not seen in other animals.


Asunto(s)
Evolución Biológica , Neuroglía/citología , Animales , Caenorhabditis elegans , Humanos , Vaina de Mielina , Neuronas/citología , Oligodendroglía/citología
18.
Adv Exp Med Biol ; 1175: 1-13, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31583582

RESUMEN

Neuroglia represent a diverse population of non-neuronal cells in the nervous systems, be that peripheral, central, enteric or autonomic nervous system. Arguably, these cells represent about half of the volume of the human brain. This volumetric ratio, and by extension glia to neurone ratio, not only widely differ depending on the size of the animal species brain and its positioning on the phylogenetic tree, but also vary between the regions of an individual brain. Neuroglia derived from a dual origin (ectoderm and mesodermal) and in an assorted morphology, yet their functional traits can be mainly classified into being keepers of homeostasis (water, ions, neurotransmitters, metabolites, fuels, etc.) and defenders (e.g., against microbial organisms, etc.) of the nervous system. As these capabilities go awry, neuroglia ultimately define their fundamental role in most, if not, all neuropathologies. This concept presented in this chapter serves as a general introduction into the world of neuroglia and subsequent topics covered by this book.


Asunto(s)
Neuroglía/fisiología , Animales , Homeostasis , Humanos , Neuronas , Neurotransmisores , Filogenia
19.
Adv Exp Med Biol ; 1175: 149-179, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31583588

RESUMEN

Astroglial cells are involved in most if not in all pathologies of the brain. These cells can change the morpho-functional properties in response to pathology or innate changes of these cells can lead to pathologies. Overall pathological changes in astroglia are complex and diverse and often vary with different disease stages. We classify astrogliopathologies into reactive astrogliosis, astrodegeneration with astroglial atrophy and loss of function, and pathological remodelling of astrocytes. Such changes can occur in neurological, neurodevelopmental, metabolic and psychiatric disorders as well as in infection and toxic insults. Mutation in astrocyte-specific genes leads to specific pathologies, such as Alexander disease, which is a leukodystrophy. We discuss changes in astroglia in the pathological context and identify some molecular entities underlying pathology. These entities within astroglia may repent targets for novel therapeutic intervention in the management of brain pathologies.


Asunto(s)
Astrocitos/patología , Encéfalo/fisiopatología , Enfermedad de Alexander/fisiopatología , Atrofia , Humanos , Trastornos Mentales/fisiopatología
20.
Clin Proteomics ; 15: 41, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30598658

RESUMEN

BACKGROUND: It may be possible to discover new diagnostic or therapeutic peptides or proteins from blood plasma by using liquid chromatography and tandem mass spectrometry to identify, quantify and compare the peptides cleaved ex vivo from different clinical populations. The endogenous tryptic peptides of ovarian cancer plasma were compared to breast cancer and female cancer normal controls, other diseases with their matched or normal controls, plus ice cold plasma to control for pre-analytical variation. METHODS: The endogenous tryptic peptides or tryptic phospho peptides (i.e. without exogenous digestion) were analyzed from 200 µl of EDTA plasma. The plasma peptides were extracted by a step gradient of organic/water with differential centrifugation, dried, and collected over C18 for analytical HPLC nano electrospray ionization and tandem mass spectrometry (LC-ESI-MS/MS) with a linear quadrupole ion trap. The endogenous peptides of ovarian cancer were compared to multiple disease and normal samples from different institutions alongside ice cold controls. Peptides were randomly and independently sampled by LC-ESI-MS/MS. Precursor ions from peptides > E4 counts were identified by the SEQUEST and X!TANDEM algorithms, filtered in SQL Server, before testing of frequency counts by Chi Square (χ2), for analysis with the STRING algorithm, and comparison of precursor intensity by ANOVA in the R statistical system with the Tukey-Kramer Honestly Significant Difference (HSD) test. RESULTS: Peptides and/or phosphopeptides of common plasma proteins such as HPR, HP, HPX, and SERPINA1 showed increased observation frequency and/or precursor intensity in ovarian cancer. Many cellular proteins showed large changes in frequency by Chi Square (χ2 > 60, p < 0.0001) in the ovarian cancer samples such as ZNF91, ZNF254, F13A1, LOC102723511, ZNF253, QSER1, P4HA1, GPC6, LMNB2, PYGB, NBR1, CCNI2, LOC101930455, TRPM5, IGSF1, ITGB1, CHD6, SIRT1, NEFM, SKOR2, SUPT20HL1, PLCE1, CCDC148, CPSF3, MORN3, NMI, XTP11, LOC101927572, SMC5, SEMA6B, LOXL3, SEZ6L2, and DHCR24. The protein gene symbols with large Chi Square values were significantly enriched in proteins that showed a complex set of previously established functional and structural relationships by STRING analysis. Analysis of the frequently observed proteins by ANOVA confirmed increases in mean precursor intensity in ZFN91, TRPM5, SIRT1, CHD6, RIMS1, LOC101930455 (XP_005275896), CCDC37 and GIMAP4 between ovarian cancer versus normal female and other diseases or controls by the Tukey-Kramer HSD test. CONCLUSION: Here we show that separation of endogenous peptides with a step gradient of organic/water and differential centrifugation followed by random and independent sampling by LC-ESI-MS/MS with analysis of peptide frequency and intensity by SQL Server and R revealed significant difference in the ex vivo cleavage of peptides between ovarian cancer and other clinical treatments. There was striking agreement between the proteins discovered from cancer plasma versus previous biomarkers discovered in tumors by genetic or biochemical methods. The results indicate that variation in plasma proteins from ovarian cancer may be directly discovered by LC-ESI-MS/MS that will be a powerful tool for clinical research.

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