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1.
Cell ; 186(18): 3862-3881.e28, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37572660

RESUMO

Male sexual behavior is innate and rewarding. Despite its centrality to reproduction, a molecularly specified neural circuit governing innate male sexual behavior and reward remains to be characterized. We have discovered a developmentally wired neural circuit necessary and sufficient for male mating. This circuit connects chemosensory input to BNSTprTac1 neurons, which innervate POATacr1 neurons that project to centers regulating motor output and reward. Epistasis studies demonstrate that BNSTprTac1 neurons are upstream of POATacr1 neurons, and BNSTprTac1-released substance P following mate recognition potentiates activation of POATacr1 neurons through Tacr1 to initiate mating. Experimental activation of POATacr1 neurons triggers mating, even in sexually satiated males, and it is rewarding, eliciting dopamine release and self-stimulation of these cells. Together, we have uncovered a neural circuit that governs the key aspects of innate male sexual behavior: motor displays, drive, and reward.


Assuntos
Vias Neurais , Comportamento Sexual Animal , Animais , Masculino , Neurônios/fisiologia , Recompensa , Comportamento Sexual Animal/fisiologia , Camundongos
2.
Cell ; 185(23): 4298-4316.e21, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36323317

RESUMO

After ingestion of toxin-contaminated food, the brain initiates a series of defensive responses (e.g., nausea, retching, and vomiting). How the brain detects ingested toxin and coordinates diverse defensive responses remains poorly understood. Here, we developed a mouse-based paradigm to study defensive responses induced by bacterial toxins. Using this paradigm, we identified a set of molecularly defined gut-to-brain and brain circuits that jointly mediate toxin-induced defensive responses. The gut-to-brain circuit consists of a subset of Htr3a+ vagal sensory neurons that transmit toxin-related signals from intestinal enterochromaffin cells to Tac1+ neurons in the dorsal vagal complex (DVC). Tac1+ DVC neurons drive retching-like behavior and conditioned flavor avoidance via divergent projections to the rostral ventral respiratory group and lateral parabrachial nucleus, respectively. Manipulating these circuits also interferes with defensive responses induced by the chemotherapeutic drug doxorubicin. These results suggest that food poisoning and chemotherapy recruit similar circuit modules to initiate defensive responses.


Assuntos
Eixo Encéfalo-Intestino , Núcleos Parabraquiais , Nervo Vago , Animais , Camundongos , Neurônios/fisiologia , Neurônios Aferentes/fisiologia , Nervo Vago/fisiologia
3.
Infect Immun ; 92(7): e0007224, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38899880

RESUMO

Invasive fungal infections impose an enormous clinical, social, and economic burden on humankind. One of the most common species responsible for invasive fungal infections is Candida albicans. More than 30% of patients with disseminated candidiasis fail therapy with existing antifungal drugs, including the widely used azole class. We previously identified a collection of 13 medications that antagonize the activity of the azoles on C. albicans. Although gain-of-function mutations responsible for antifungal resistance are often associated with reduced fitness and virulence, it is currently unknown how exposure to azole antagonistic drugs impacts C. albicans physiology, fitness, or virulence. In this study, we examined how exposure to seven azole antagonists affects C. albicans phenotype and capacity to cause disease. Most of the azole antagonists appear to have little impact on fungal growth, morphology, stress tolerance, or gene transcription. However, aripiprazole had a modest impact on C. albicans hyphal growth and increased cell wall chitin content. It also aggravated the disseminated C. albicans infections in mice. This effect was abrogated in immunosuppressed mice, indicating that it is at least in part dependent upon host immune responses. Collectively, these data provide proof of principle that unanticipated drug-fungus interactions have the potential to influence the incidence and outcomes of invasive fungal disease.


Assuntos
Antifúngicos , Aripiprazol , Candida albicans , Candidíase , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Animais , Camundongos , Antifúngicos/farmacologia , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Aripiprazol/farmacologia , Aripiprazol/uso terapêutico , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Virulência , Feminino , Azóis/farmacologia , Modelos Animais de Doenças
4.
Antimicrob Agents Chemother ; : e0002224, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38624217

RESUMO

Candida parapsilosis has recently emerged as a major threat due to the worldwide emergence of fluconazole-resistant strains causing clonal outbreaks in hospitals and poses a therapeutic challenge due to the limited antifungal armamentarium. Here, we used precise genome editing using CRISPR-Cas9 to gain further insights into the contribution of mutations in ERG11, ERG3, MRR1, and TAC1 genes and the influence of allelic dosage to antifungal resistance in C. parapsilosis. Seven of the most common amino acid substitutions previously reported in fluconazole-resistant clinical isolates (including Y132F in ERG11) were engineered in two fluconazole-susceptible C. parapsilosis lineages (ATCC 22019 and STZ5). Each mutant was then challenged in vitro against a large array of antifungals, with a focus on azoles. Any possible change in virulence was also assessed in a Galleria mellonella model. We successfully generated a total of 19 different mutants, using CRISPR-Cas9. Except for R398I (ERG11), all remaining amino acid substitutions conferred reduced susceptibility to fluconazole. However, the impact on fluconazole in vitro susceptibility varied greatly according to the engineered mutation, the stronger impact being noted for G583R acting as a gain-of-function mutation in MRR1. Cross-resistance with newer azoles, non-medical azoles, but also non-azole antifungals such as flucytosine, was occasionally noted. Posaconazole and isavuconazole remained the most active in vitro. Except for G583R, no fitness cost was associated with the acquisition of fluconazole resistance. We highlight the distinct contributions of amino acid substitutions in ERG11, ERG3, MRR1, and TAC1 genes to antifungal resistance in C. parapsilosis.

5.
Mol Pain ; 18: 17448069221119614, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-36000342

RESUMO

Projection neurons belonging to the anterolateral system (ALS) underlie the perception of pain, skin temperature and itch. Many ALS cells are located in laminae III-V of the dorsal horn and the adjacent lateral white matter. However, relatively little is known about the excitatory synaptic input to these deep ALS cells, and therefore about their engagement with the neuronal circuitry of the region. We have used a recently developed mouse line, Phox2a::Cre, to investigate a population of deep dorsal horn ALS neurons known as "antenna cells", which are characterised by dense innervation from peptidergic nociceptors, and to compare these with other ALS cells in the deep dorsal horn and lateral white matter. We show that these two classes differ, both in the density of excitatory synapses, and in the source of input at these synapses. Peptidergic nociceptors account for around two-thirds of the excitatory synapses on the antenna cells, but for only a small proportion of the input to the non-antenna cells. Conversely, boutons with high levels of VGLUT2, which are likely to originate mainly from glutamatergic spinal neurons, account for only ∼5% of the excitatory synapses on antenna cells, but for a much larger proportion of the input to the non-antenna cells. VGLUT1 is expressed by myelinated low-threshold mechanoreceptors and corticospinal axons, and these innervate both antenna and non-antenna cells. However, the density of VGLUT1 input to the non-antenna cells is highly variable, consistent with the view that these neurons are functionally heterogeneous.


Assuntos
Esclerose Lateral Amiotrófica , Animais , Proteínas de Homeodomínio/genética , Integrases , Camundongos , Neurônios/fisiologia , Células do Corno Posterior/fisiologia , Medula Espinal , Corno Dorsal da Medula Espinal
6.
Fungal Genet Biol ; 163: 103743, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36152775

RESUMO

Feline-transmitted sporotrichosis has garnered attention due to the recent high incidence and the lack of efficient control in the epicenter of the epidemic, Rio de Janeiro, Brazil. Sporothrix brasiliensis is the major pathogen involved in feline-to-human sporotrichosis in Brazil and displays more virulent genotypes than the closely related species S. schenckii. Over the last two decades, several reports of antifungal-resistant strains have emerged. Sequencing and comparison analysis of the outbreak strains allowed us to observe that the azole non-wild-type S. brasiliensis strain CFP 1054 had significant chromosomal variations compared to wild-type strains. One of these variants includes a region of 231 Kb containing 75 duplicated genes, which were overrepresented for lipid and isoprenoid metabolism. We also identified an additional strain (CFP 1055) that was resistant to itraconazole and amphotericin B, which had a single nucleotide polymorphism in the tac1 gene. The patients infected with these two strains showed protracted clinical course and sequelae. Even though our sample size is modest, these results suggest the possibility of identifying specific point mutations and large chromosomal duplications potentially associated with antifungal resistance and clinical outcomes of sporotrichosis.


Assuntos
Sporothrix , Esporotricose , Animais , Gatos , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Brasil/epidemiologia , Variações do Número de Cópias de DNA , Polimorfismo de Nucleotídeo Único , Sporothrix/genética , Esporotricose/epidemiologia , Esporotricose/microbiologia , Farmacorresistência Fúngica/genética
7.
New Phytol ; 233(6): 2354-2379, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34890051

RESUMO

Shoot morphogenetic plasticity is crucial to the adaptation of plants to their fluctuating environments. Major insights into shoot morphogenesis have been compiled studying meristems, especially the shoot apical meristem (SAM), through a methodological effort in multiscale systems biology and biophysics. However, morphogenesis at the SAM is robust to environmental changes. Plasticity emerges later on during post-SAM development. The purpose of this review is to show that multiscale systems biology and biophysics is insightful for the shaping of the whole plant as well. More specifically, we review the shaping of axes and crowns through tropisms and elasticity, combining the recent advances in morphogenetic control using physical cues and by genes. We focus mostly on land angiosperms, but with growth habits ranging from small herbs to big trees. We show that generic (universal) morphogenetic processes have been identified, revealing feedforward and feedback effects of global shape on the local morphogenetic process. In parallel, major advances have been made in the analysis of the major genes involved in shaping axes and crowns, revealing conserved genic networks among angiosperms. Then, we show that these two approaches are now starting to converge, revealing exciting perspectives.


Assuntos
Meristema , Tropismo , Elasticidade , Meristema/genética , Morfogênese , Brotos de Planta
8.
Mol Biol Rep ; 49(12): 11625-11633, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36169896

RESUMO

BACKGROUND: Candida albicans (C. albicans) is an opportunistic fungus and the most common cause of vulvovaginal candidiasis (VVC). In recent years, the use of antifungal drugs has led to the incidence of drug-resistant C. albicans strains. The purpose of this study is twofold: to determine the pattern of drug susceptibility and the relationship between demographic factors and the incidence of drug resistance among C. albicans isolates and to investigate the expression pattern of drug-resistance genes ERG11 and TAC1 in C. albicans isolates. METHODS AND RESULTS: This descriptive cross-sectional study was conducted on 50 C. albicans isolates from women with VVC. Antifungal susceptibility of the isolates was tested by M27-A3/S4 broth micro dilution method following the Clinical and Laboratory Standards Institute (CLSI) guidelines. High susceptibility rates were recorded for itraconazole and voriconazole (68%), followed by ketoconazole (46%). Fluconazole had the lowest susceptibility to C. albicans with susceptibility of 36%. The change in ERG11 and TAC1 genes expression was determined by qPCR. The mean ∆Ct values of ERG11 and TAC1genes were significantly different between fluconazole-resistant and susceptible groups (p < 0.001). Interestingly, we found that 77% of fluconazole-susceptible isolates had significantly upregulated ERG11 gene (2.9-99.0 fold). In addition, the expression of TAC1 was upregulated in 44% of fluconazole-susceptible isolates (3.86-89.8 fold). CONCLUSION: Our finding revealed that incidence of drug resistance in C. albicans is not simply controlled by genes but is a multi-factorial phenomenon, where several factors and mechanisms are involved in the process of drug resistance.


Assuntos
Candida albicans , Fluconazol , Feminino , Humanos , Fluconazol/farmacologia , Antifúngicos/farmacologia , Farmacorresistência Fúngica/genética , Estudos Transversais , Testes de Sensibilidade Microbiana
9.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563391

RESUMO

Plant architecture is dynamic as plants develop. Although many genes associated with specific plant architecture components have been identified in rice, genes related to underlying dynamic changes in plant architecture remain largely unknown. Here, we identified two highly similar recombinant inbred lines (RILs) with different plant architecture: RIL-Dynamic (D) and RIL-Compact (C). The dynamic plant architecture of RIL-D is characterized by 'loosetiller angle (tillering stage)-compact (heading stage)-loosecurved stem (maturing stage)' under natural long-day (NLD) conditions, and 'loosetiller angle (tillering and heading stages)-loosetiller angle and curved stem (maturing stage)' under natural short-day (NSD) conditions, while RIL-C exhibits a compact plant architecture both under NLD and NSD conditions throughout growth. The candidate locus was mapped to the chromosome 9 tail via the rice 8K chip assay and map-based cloning. Sequencing, complementary tests, and gene knockout tests demonstrated that Tiller Angle Control 1 (TAC1) is responsible for dynamic plant architecture in RIL-D. Moreover, TAC1 positively regulates loose plant architecture, and high TAC1 expression cannot influence the expression of tested tiller-angle-related genes. Our results reveal that TAC1 is necessary for the dynamic changes in plant architecture, which can guide improvements in plant architecture during the modern super rice breeding.


Assuntos
Oryza , Oryza/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
10.
Med Mycol ; 58(6): 766-773, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31828316

RESUMO

Candida tropicalis is one of the major candidaemia agents, associated with the highest mortality rates among Candida species, and developing resistance to azoles. Little is known about the molecular mechanisms of azole resistance, genotypic diversity, and the clinical background of C. tropicalis infections. Consequently, this study was designed to address those questions. Sixty-four C. tropicalis bloodstream isolates from 62 patients from three cities in Iran (2014-2019) were analyzed. Strain identification, antifungal susceptibility testing, and genotypic diversity analysis were performed by MALDI-TOF MS, CLSI-M27 A3/S4 protocol, and amplified fragment length polymorphism (AFLP) fingerprinting, respectively. Genes related to drug resistance (ERG11, MRR1, TAC1, UPC2, and FKS1 hotspot9s) were sequenced. The overall mortality rate was 59.6% (37/62). Strains were resistant to micafungin [minimum inhibitory concentration (MIC) ≥1 µg/ml, 2/64], itraconazole (MIC > 0.5 µg/ml, 2/64), fluconazole (FLZ; MIC ≥ 8 µg/ml, 4/64), and voriconazole (MIC ≥ 1 µg/ml, 7/64). Pan-azole and FLZ + VRZ resistance were observed in one and two isolates, respectively, while none of the patients were exposed to azoles. MRR1 (T255P, 647S), TAC1 (N164I, R47Q), and UPC2 (T241A, Q340H, T381S) mutations were exclusively identified in FLZ-resistant isolates. AFLP fingerprinting revealed five major and seven minor genotypes; genotype G4 was predominant in all centers. The increasing number of FLZ-R C. tropicalis blood isolates and acquiring FLZ-R in FLZ-naive patients limit the efficiency of FLZ, especially in developing countries. The high mortality rate warrants reaching a consensus regarding the nosocomial mode of C. tropicalis transmission.


Assuntos
Antifúngicos/farmacologia , Candida tropicalis/efeitos dos fármacos , Candida tropicalis/genética , Farmacorresistência Fúngica/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Candidemia/microbiologia , Candidemia/mortalidade , Criança , Pré-Escolar , Feminino , Variação Genética , Genótipo , Técnicas de Genotipagem , Humanos , Lactente , Irã (Geográfico)/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , Adulto Jovem
11.
Artigo em Inglês | MEDLINE | ID: mdl-30858206

RESUMO

The increasing incidence of and high mortality rates associated with invasive fungal infections (IFIs) impose an enormous clinical, social, and economic burden on humankind. In addition to microbiological resistance to existing antifungal drugs, the large number of unexplained treatment failures is a serious concern. Due to the extremely limited therapeutic options available, it is critical to identify and understand the various causes of treatment failure if patient outcomes are to improve. In this study, we examined one potential source of treatment failure: antagonistic drug interactions. Using a simple screen, we systematically identified currently approved medications that undermine the antifungal activity of three major antifungal drugs-fluconazole, caspofungin, and amphotericin B-on four prevalent human fungal pathogens-Candida albicans, Candida glabrata, Candida parapsilosis, and Candida tropicalis This revealed that a diverse collection of structurally distinct drugs exhibit antagonistic interactions with fluconazole. Several antagonistic agents selected for follow-up studies induce azole resistance through a mechanism that depends on Tac1p/Pdr1p zinc-cluster transcription factors, which activate the expression of drug efflux pumps belonging to the ABC-type transporter family. Few antagonistic interactions were identified with caspofungin or amphotericin B, possibly reflecting their cell surface mode of action that should not be affected by drug efflux mechanisms. Given that patients at greatest risk of IFIs usually receive a multitude of drugs to treat various underlying conditions, these studies suggest that chemically inducible azole resistance may be much more common and important than previously realized.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Azóis/farmacologia , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Haloperidol/farmacologia , Humanos , Morfolinas/farmacologia
12.
Plant J ; 89(6): 1093-1105, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28029738

RESUMO

Roots provide essential uptake of water and nutrients from the soil, as well as anchorage and stability for the whole plant. Root orientation, or angle, is an important component of the overall architecture and depth of the root system; however, little is known about the genetic control of this trait. Recent reports in Oryza sativa (rice) identified a role for DEEPER ROOTING 1 (DRO1) in influencing the orientation of the root system, leading to positive changes in grain yields under water-limited conditions. Here we found that DRO1 and DRO1-related genes are present across diverse plant phyla, and fall within the IGT gene family. The IGT family also includes TAC1 and LAZY1, which are known to affect the orientation of lateral shoots. Consistent with a potential role in root development, DRO1 homologs in Arabidopsis and peach showed root-specific expression. Promoter-reporter constructs revealed that AtDRO1 is predominantly expressed in both the root vasculature and root tips, in a distinct developmental pattern. Mutation of AtDRO1 led to more horizontal lateral root angles. Overexpression of AtDRO1 under a constitutive promoter resulted in steeper lateral root angles, as well as shoot phenotypes including upward leaf curling, shortened siliques and narrow lateral branch angles. A conserved C-terminal EAR-like motif found in IGT genes was required for these ectopic phenotypes. Overexpression of PpeDRO1 in Prunus domestica (plum) led to deeper-rooting phenotypes. Collectively, these data indicate a potential application for DRO1-related genes to alter root architecture for drought avoidance and improved resource use.


Assuntos
Arabidopsis/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Prunus/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Gravitropismo/genética , Gravitropismo/fisiologia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Prunus/genética , Prunus/fisiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-28807920

RESUMO

The human fungal pathogen Candida albicans develops drug resistance after long-term exposure to azole drugs in the treatment of chronic candidiasis. Gain-of-function (GOF) mutations in the transcription factor Tac1 and the consequent expression of its targets, drug efflux pumps Cdr1 and Cdr2, are a common mechanism by which C. albicans acquires fluconazole resistance. The mechanism by which GOF mutations hyperactivate Tac1 is currently unknown. Here, we define a transcriptional activation domain (TAD) at the C terminus of Tac1. GOF mutations within the Tac1 TAD, outside the context of full-length Tac1, generally do not enhance its absolute potential as a transcriptional activator. Negative regulation of the Tac1 TAD by the Tac1 middle region is necessary for the activating effect of GOF mutations or fluphenazine to be realized. We have found that full-length Tac1, when hyperactivated by xenobiotics or GOF mutations, facilitates the recruitment of the Mediator coactivator complex to the CDR1 promoter. Azole resistance and the activation of Tac1 target genes, such as CDR1, are dependent on the Tac1 TAD and subunits of the Mediator tail module. The dependence of different Tac1 target promoters on the Mediator tail module, however, varies widely. Lastly, we show that hyperactivation of Tac1 is correlated with its Mediator-dependent phosphorylation, a potentially useful biomarker for Tac1 hyperactivation. The role of Mediator in events downstream of Tac1 hyperactivation in fluconazole-resistant clinical isolates is complex and provides opportunities and challenges for therapeutic intervention.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida albicans/efeitos dos fármacos , Farmacorresistência Fúngica/fisiologia , Proteínas Fúngicas/metabolismo , Candida albicans/patogenicidade , Eletroforese em Gel de Poliacrilamida , Fluconazol/farmacologia , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Mutação , Regiões Promotoras Genéticas , Domínios Proteicos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Xenobióticos/farmacologia
14.
Microb Drug Resist ; 30(7): 288-296, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38770776

RESUMO

Candidiasis is a common fungal infection caused by Candida species, with Candida albicans being the most prevalent. Resistance to azole drugs, commonly used to treat Candida infections, poses a significant challenge. Transcriptional activator candidate 1 (TAC1) gene has emerged as a key player in regulating drug resistance in C. albicans. This review explores the structure and function of the TAC1 gene and its role in azole resistance. This gene encodes a transcription factor that controls the expression of genes involved in drug resistance, such as efflux pump genes (CDR1, CDR2, and MDR1) and ERG11. Mutations in TAC1 can increase these genes' expression and confer resistance to azoles. Various TAC1 gene mutations, mostly gain-of-function mutations, have been identified, which upregulate CDR1 and CDR2 expression, resulting in azole resistance. Understanding the mechanisms of azole resistance mediated by the TAC1 gene is crucial for the strategies in the effective antifungal development pipeline.


Assuntos
Antifúngicos , Azóis , Candida albicans , Farmacorresistência Fúngica , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Antifúngicos/farmacologia , Azóis/farmacologia , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Humanos , Mutação , Testes de Sensibilidade Microbiana , Fatores de Transcrição/genética , Candidíase/tratamento farmacológico , Candidíase/microbiologia
15.
mSphere ; 9(7): e0027024, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38860767

RESUMO

Zinc cluster transcription factors (ZCFs) are a family of transcription regulators that are almost exclusively found in the fungal kingdom. Activating mutations in the ZCFs Mrr1, Tac1, and Upc2 frequently cause acquired resistance to the widely used antifungal drug fluconazole in the pathogenic yeast Candida albicans. Similar to a hyperactive Tac1, a constitutively active form of the ZCF Znc1 causes increased fluconazole resistance by upregulating the multidrug efflux pump-encoding gene CDR1. Hyperactive forms of both Tac1 and Znc1 also cause overexpression of RTA3, which encodes a seven-transmembrane receptor protein involved in the regulation of asymmetric lipid distribution in the plasma membrane. RTA3 expression is also upregulated by miltefosine, an antiparasitic drug that is active against fungal pathogens and considered for treatment of invasive candidiasis, and rta3Δ mutants are hypersensitive to miltefosine. We found that activated forms of both Tac1 and Znc1 confer increased miltefosine resistance, which was dependent on RTA3 whereas CDR1 was dispensable. Intriguingly, the induction of RTA3 expression by miltefosine depended on Znc1, but not Tac1, in contrast to the known Tac1-dependent RTA3 upregulation by fluphenazine. In line with this observation, znc1Δ mutants were hypersensitive to miltefosine, whereas tac1Δ mutants showed wild-type tolerance. Forced expression of RTA3 reverted the hypersensitivity of znc1Δ mutants, demonstrating that the hypersensitivity was caused by the inability of the mutants to upregulate RTA3 in response to the drug. These findings establish Znc1 as a key regulator of miltefosine-induced RTA3 expression that is important for wild-type miltefosine tolerance. IMPORTANCE: Transcription factors are central regulators of gene expression, and knowledge about which transcription factor regulates specific genes in response to a certain signal is important to understand the behavior of organisms. In the pathogenic yeast Candida albicans, the RTA3 gene is required for wild-type tolerance of miltefosine, an antiparasitic drug that is considered for treatment of invasive candidiasis. Activated forms of the transcription factors Tac1 and Znc1 cause constitutive overexpression of RTA3 and thereby increased miltefosine resistance, but only Tac1 mediates upregulation of RTA3 in response to the known inducer fluphenazine. RTA3 expression is also induced by miltefosine, and we found that this response depends on Znc1, whereas Tac1 is dispensable. Consequently, znc1Δ mutants were hypersensitive to miltefosine, whereas tac1Δ mutants showed wild-type tolerance. These findings demonstrate that Znc1 is the key regulator of RTA3 expression in response to miltefosine that is important for wild-type miltefosine tolerance.


Assuntos
Antifúngicos , Candida albicans , Farmacorresistência Fúngica , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Fosforilcolina , Fatores de Transcrição , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Farmacorresistência Fúngica/genética , Antifúngicos/farmacologia , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-39411944

RESUMO

OBJECTIVE: In this study, we aimed to identify novel biomarkers related to Peripheral Neural Invasion (PNI) in head and neck squamous cell carcinoma (HNSCC). METHODS: The PNI-related differentially expressed mRNAs (DE-mRNAs) in HNSCC were identified to construct a PNI-related risk score model. The expression level and ROC curve for Tachykinin Precursor 1 (TAC1) were calculated. Additionally, two kinds of in vitro models of PNI were established for investigation, including the Matrigel-PNI model and the Transwell-PNI model. Furthermore, the transcription factor of the TAC1 was predicted and verified by qRTPCR. RESULTS: A total of 139 DE-mRNAs were identified in PNI positive and negative groups of HNSCC patients. The risk-score marker model incorporating 20 PNI-related DE-mRNAs was established. The TAC1 was identified as a potential highly expressed PNI marker, which exhibited good performance in predicting PNI events. Patients with higher TAC1 expressions demonstrated significantly shorter survival rates compared to those with lower TAC1 expressions in HNSCC. Besides, the knockdown of TAC1 significantly repressed neural invasion in HNSCC cells in vitro, according to the Matrigel-PNI model and Transwell-PNI model. Furthermore, KLF15 was predicted and verified as a transcription activator of TAC1 in HNSCC. CONCLUSION: This study highlights that the activation of KLF15 transcription of TAC1 promotes PNI in HNSCC cells, which provides guidance regarding the molecular diagnosis of PNI in HNSCC cells.

17.
Elife ; 122023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37458576

RESUMO

Rhythmic breathing is generated by neural circuits located in the brainstem. At its core is the preBötzinger Complex (preBötC), a region of the medulla, necessary for the generation of rhythmic breathing in mammals. The preBötC is comprised of various neuronal populations expressing neurokinin-1 receptors, the cognate G-protein-coupled receptor of the neuropeptide substance P (encoded by the tachykinin precursor 1 or Tac1). Neurokinin-1 receptors are highly expressed in the preBötC and destruction or deletion of neurokinin-1 receptor-expressing preBötC neurons severely impair rhythmic breathing. Although, the application of substance P to the preBötC stimulates breathing in rodents, substance P is also involved in nociception and locomotion in various brain regions, suggesting that Tac1 neurons found in the preBötC may have diverse functional roles. Here, we characterized the role of Tac1-expressing preBötC neurons in the generation of rhythmic breathing in vivo, as well as motor behaviors. Using a cre-lox recombination approach, we injected adeno-associated virus containing the excitatory channelrhodopsin-2 ChETA in the preBötC region of Tac1-cre mice. Employing a combination of histological, optogenetics, respiratory, and behavioral assays, we showed that stimulation of glutamatergic or Tac1 preBötC neurons promoted rhythmic breathing in both anesthetized and freely moving animals, but also triggered locomotion and overcame respiratory depression by opioid drugs. Overall, our study identified a population of excitatory preBötC with major roles in rhythmic breathing and behaviors.


Assuntos
Receptores da Neurocinina-1 , Substância P , Camundongos , Animais , Receptores da Neurocinina-1/genética , Neurônios/fisiologia , Bulbo/fisiologia , Respiração , Centro Respiratório/fisiologia , Mamíferos
18.
Clin Microbiol Infect ; 29(12): 1602.e1-1602.e7, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37666448

RESUMO

OBJECTIVES: The aim of this study was to determine how mutations in CpERG11 and CpTAC1 contribute to fluconazole resistance in a collection of clinical isolates. METHODS: Sequences of CpERG11 and CpTAC1 were determined for 35 resistant Candida parapsilosis clinical isolates. A plasmid-based CRISPR-Cas9 system was used to introduce mutations leading to amino acid substitution in CpTac1 and CpErg11. Triazole susceptibility was determined by broth microdilution and E-test. Differential expression of genes mediated by CpTAC1 mutation was determined by RNA sequencing, and relative expression of individual transporter genes was assessed with RT-qPCR. RESULTS: Six isolates carried a mutation in CpTAC1 in combination with the CpERG11 mutation, leading to the CpErg11Y132F substitution. When introduced into susceptible isolates, this CpERG11 mutation led to a 4- to 8-fold increase in fluconazole minimum inhibitory concentrations (MIC; 0.125 µg/mL vs. 0.5 µg/mL, 0.125 µg/mL vs. 0.5 µg/mL, and 0.5 µg/mL vs. 4 µg/mL). When introduced into a susceptible isolate, the CpTAC1 mutation leading to the G650E substitution resulted in an 8-fold increase in fluconazole MIC (0.25 µg/mL vs. 2 µg/mL), whereas correction of this mutation in resistant isolates led to a 16-fold reduction in MIC (32 µg/mL vs. 2 µg/mL). CpCDR1, CpCDR1B, and CpCDR1C were overexpressed in the presence CpTac1G650E. Disruption of these genes in combination resulted in a 4-fold reduction in fluconazole MIC (32 µg/mL vs. 8 µg/mL). DISCUSSION: These results define the specific contribution made by the Y132F substitution in CpERG11 and demonstrate a role for activating mutations in CpTAC1 in triazole resistance in C. parapsilosis.


Assuntos
Antifúngicos , Fluconazol , Humanos , Antifúngicos/farmacologia , Fluconazol/farmacologia , Candida parapsilosis/genética , Triazóis/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mutação , Farmacorresistência Fúngica/genética , Testes de Sensibilidade Microbiana
19.
Front Immunol ; 14: 1099017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122730

RESUMO

Periodontitis is one of the most common oral diseases in humans, affecting over 40% of adult Americans. Pain-sensing nerves, or nociceptors, sense local environmental changes and often contain neuropeptides. Recent studies have suggested that nociceptors magnify host response and regulate bone loss in the periodontium. A subset of nociceptors projected to periodontium contains neuropeptides, such as calcitonin gene-related peptide (CGRP) or substance P (SP). However, the specific roles of neuropeptides from nociceptive neural terminals in periodontitis remain to be determined. In this study, we investigated the roles of neuropeptides on host responses and bone loss in ligature-induced periodontitis. Deletion of tachykinin precursor 1 (Tac1), a gene that encodes SP, or treatment of gingiva with SP antagonist significantly reduced bone loss in ligature-induced periodontitis, whereas deletion of calcitonin related polypeptide alpha (Calca), a gene that encodes CGRP, showed a marginal role on bone loss. Ligature-induced recruitment of leukocytes, including neutrophils, and increase in cytokines leading to bone loss in periodontium was significantly less in Tac1 knockout mice. Furthermore, intra-gingival injection of SP, but not neurokinin A, induced a vigorous inflammatory response and osteoclast activation in alveolar bone and facilitated bone loss in ligature-induced periodontitis. Altogether, our data suggest that SP plays significant roles in regulating host responses and bone resorption in ligature-induced periodontitis.


Assuntos
Perda do Osso Alveolar , Periodontite , Substância P , Animais , Humanos , Camundongos , Perda do Osso Alveolar/etiologia , Peptídeo Relacionado com Gene de Calcitonina , Osteoclastos
20.
Front Plant Sci ; 14: 1320638, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38356867

RESUMO

Introduction: Plants can adapt their growth to optimize light capture in competitive environments, with branch angle being a crucial factor influencing plant phenotype and physiology. Decreased branch angles in cereal crops have been shown to enhance productivity in high-density plantings. The Tiller Angle Control (TAC1) gene, known for regulating tiller inclination in rice and corn, has been found to control branch angle in eudicots. Manipulating TAC1 in field crops like cotton offers the potential for improving crop productivity. Methods: Using a homolog-based methodology, we examined the distribution of TAC1-related genes in cotton compared to other angiosperms. Furthermore, tissue-specific qPCR analysis unveiled distinct expression patterns of TAC1 genes in various cotton tissues. To silence highly expressed specific TAC1 homeologs in the stem, we applied CRISPR-Cas9 gene editing and Agrobacterium-mediated transformation, followed by genotyping and subsequent phenotypic validation of the mutants. Results: Gene duplication events of TAC1 specific to the Gossypium lineage were identified, with 3 copies in diploid progenitors and 6 copies in allotetraploid cottons. Sequence analysis of the TAC1 homeologs in Gossypium hirsutum revealed divergence from other angiosperms with 1-2 copies, suggesting possible neo- or sub-functionalization for the duplicated copies. These TAC1 homeologs exhibited distinct gene expression patterns in various tissues over developmental time, with elevated expression of A11G109300 and D11G112200, specifically in flowers and stems, respectively. CRISPR-mediated loss of these TAC1 homeologous genes resulted in a reduction in branch angle and altered petiole angles, and a 5 to 10-fold reduction in TAC1 expression in the mutants, confirming their role in controlling branch and petiole angles. This research provides a promising strategy for genetically engineering branch and petiole angles in commercial cotton varieties, potentially leading to increased productivity.

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