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1.
J Cell Sci ; 137(8)2024 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-38482739

RESUMEN

CSL proteins [named after the homologs CBF1 (RBP-Jκ in mice), Suppressor of Hairless and LAG-1] are conserved transcription factors found in animals and fungi. In the fission yeast Schizosaccharomyces pombe, they regulate various cellular processes, including cell cycle progression, lipid metabolism and cell adhesion. CSL proteins bind to DNA through their N-terminal Rel-like domain and central ß-trefoil domain. Here, we investigated the importance of DNA binding for CSL protein functions in fission yeast. We created CSL protein mutants with disrupted DNA binding and found that the vast majority of CSL protein functions depend on intact DNA binding. Specifically, DNA binding is crucial for the regulation of cell adhesion, lipid metabolism, cell cycle progression, long non-coding RNA expression and genome integrity maintenance. Interestingly, perturbed lipid metabolism leads to chromatin structure changes, potentially linking lipid metabolism to the diverse phenotypes associated with CSL protein functions. Our study highlights the critical role of DNA binding for CSL protein functions in fission yeast.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Factores de Transcripción , Schizosaccharomyces/metabolismo , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Unión Proteica , Metabolismo de los Lípidos/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Ciclo Celular/genética , Regulación Fúngica de la Expresión Génica , ADN de Hongos/metabolismo , ADN de Hongos/genética
2.
Development ; 150(11)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37294169

RESUMEN

Active Notch signalling is elicited through receptor-ligand interactions that result in release of the Notch intracellular domain (NICD), which translocates into the nucleus. NICD activates transcription at target genes, forming a complex with the DNA-binding transcription factor CSL [CBF1/Su(H)/LAG-1] and co-activator Mastermind. However, CSL lacks its own nuclear localisation sequence, and it remains unclear where the tripartite complex is formed. To probe the mechanisms involved, we designed an optogenetic approach to control NICD release (OptIC-Notch) and monitored the subsequent complex formation and target gene activation. Strikingly, we observed that, when uncleaved, OptIC-Notch sequestered CSL in the cytoplasm. Hypothesising that exposure of a juxta membrane ΦWΦP motif is key to sequestration, we masked this motif with a second light-sensitive domain (OptIC-Notch{ω}), which was sufficient to prevent CSL sequestration. Furthermore, NICD produced by light-induced cleavage of OptIC-Notch or OptIC-Notch{ω} chaperoned CSL into the nucleus and induced target gene expression, showing efficient light-controlled activation. Our results demonstrate that exposure of the ΦWΦP motif leads to CSL recruitment and suggest this can occur in the cytoplasm prior to nuclear entry.


Asunto(s)
Receptores Notch , Factores de Transcripción , Receptores Notch/metabolismo , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica , Activación Transcripcional , Transducción de Señal/fisiología
3.
J Biol Chem ; 300(7): 107451, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38844131

RESUMEN

Complement receptor 1 (CR1) is a membrane glycoprotein with a highly duplicated domain structure able to bind multiple ligands such as C3b and C4b, the activated fragments of complement components C3 and C4, respectively. We have previously used our knowledge of this domain structure to identify CSL040, a soluble extracellular fragment of CR1 containing the long homologous repeat (LHR) domains A, B, and C. CSL040 retains the ability to bind both C3b and C4b but is also a more potent complement inhibitor than other recombinant CR1-based therapeutics. To generate soluble CR1 variants with increased inhibitory potential across all three complement pathways, or variants with activity skewed to specific pathways, we exploited the domain structure of CR1 further by generating LHR domain duplications. We identified LHR-ABCC, a soluble CR1 variant containing a duplicated C3b-binding C-terminal LHR-C domain that exhibited significantly enhanced alternative pathway inhibitory activity in vitro compared to CSL040. Another variant, LHR-BBCC, containing duplications of both LHR-B and LHR-C with four C3b binding sites, was shown to have reduced classical/lectin pathway inhibitory activity compared to CSL040, but comparable alternative pathway activity. Interestingly, multiplication of the C4b-binding LHR-A domain resulted in only minor increases in classical/lectin pathway inhibitory activity. The CR1 duplication variants characterized in these in vitro potency assays, as well as in affinity in solution C3b and C4b binding assays, not only provides an opportunity to identify new therapeutic molecules but also additional mechanistic insights to the multiple interactions between CR1 and C3b/C4b.


Asunto(s)
Complemento C3b , Dominios Proteicos , Humanos , Complemento C3b/metabolismo , Complemento C3b/química , Complemento C3b/genética , Receptores de Complemento 3b/metabolismo , Receptores de Complemento 3b/genética , Receptores de Complemento 3b/química , Complemento C4b/metabolismo , Complemento C4b/genética , Complemento C4b/química , Unión Proteica
4.
J Cell Sci ; 136(11)2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37288768

RESUMEN

Mitotic fidelity is crucial for the faithful distribution of genetic information into the daughter cells. Many fungal species, including the fission yeast Schizosaccharomyces pombe, undergo a closed form of mitosis, during which the nuclear envelope does not break down. In S. pombe, numerous processes have been identified that contribute to successful completion of mitosis. Notably, perturbations of lipid metabolism can lead to catastrophic mitosis and the 'cut' phenotype. It has been suggested that these mitotic defects are caused by insufficient membrane phospholipid supply during the anaphase nuclear expansion. However, it is not clear whether additional factors are involved. In this study, we characterized in detail mitosis in an S. pombe mutant lacking the Cbf11 transcription factor, which regulates lipid metabolism genes. We show that in cbf11Δ cells mitotic defects have already appeared prior to anaphase, before the nuclear expansion begins. Moreover, we identify altered cohesin dynamics and centromeric chromatin structure as additional factors affecting mitotic fidelity in cells with disrupted lipid homeostasis, providing new insights into this fundamental biological process.


Asunto(s)
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Proteínas de Schizosaccharomyces pombe/metabolismo , Metabolismo de los Lípidos/genética , Schizosaccharomyces/metabolismo , Mitosis/genética , Cohesinas
5.
Eur Heart J ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39221651

RESUMEN

BACKGROUND AND AIMS: In the AEGIS-II trial (NCT03473223), CSL112, a human apolipoprotein A1 derived from plasma that increases cholesterol efflux capacity, did not significantly reduce the risk of the primary endpoint through 90 days versus placebo after acute myocardial infarction (MI). Nevertheless, given the well-established relationship between higher low-density lipoprotein cholesterol (LDL-C) and plaque burden, as well as greater risk reductions seen with PCSK9 inhibitors in patients with baseline LDL-C ≥100 mg/dL on statin therapy, the efficacy of CSL112 may be influenced by baseline LDL-C. METHODS: Overall, 18,219 patients with acute MI, multivessel coronary artery disease, and additional risk factors were randomized to either four weekly infusions of 6 g CSL112 or placebo. This exploratory post-hoc analysis evaluated cardiovascular outcomes by baseline LDL-C in patients prescribed guideline-directed statin therapy at the time of randomization (n=15,731). RESULTS: As baseline LDL-C increased, risk of the primary endpoint at 90 days lowered in those treated with CSL112 compared with placebo. In patients with LDL-C ≥100 mg/dL at randomization, there was a significant risk reduction of cardiovascular death, MI, or stroke in the CSL112 vs. placebo group at 90, 180, and 365 days (hazard ratio 0.69 [0.53-0.90], 0.71 [0.57-0.88], and 0.78 [0.65-0.93]). In contrast, there was no difference between treatment groups among those with LDL-C <100 mg/dL at baseline. CONCLUSIONS: In this population, treatment with CSL112 compared to placebo was associated with a significantly lower risk of recurrent cardiovascular events among patients with a baseline LDL-C ≥100 mg/dL. Further studies need to confirm that CSL112 efficacy is influenced by baseline LDL-C.

6.
J Allergy Clin Immunol ; 153(3): 672-683.e6, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37931708

RESUMEN

BACKGROUND: Patients with severe asthma can present with eosinophilic type 2 (T2), neutrophilic, or mixed inflammation that drives airway remodeling and exacerbations and represents a major treatment challenge. The common ß (ßc) receptor signals for 3 cytokines, GM-CSF, IL-5, and IL-3, which collectively mediate T2 and neutrophilic inflammation. OBJECTIVE: To determine the pathogenesis of ßc receptor-mediated inflammation and remodeling in severe asthma and to investigate ßc antagonism as a therapeutic strategy for mixed granulocytic airway disease. METHODS: ßc gene expression was analyzed in bronchial biopsy specimens from patients with mild-to-moderate and severe asthma. House dust mite extract and Aspergillus fumigatus extract (ASP) models were used to establish asthma-like pathology and airway remodeling in human ßc transgenic mice. Lung tissue gene expression was analyzed by RNA sequencing. The mAb CSL311 targeting the shared cytokine binding site of ßc was used to block ßc signaling. RESULTS: ßc gene expression was increased in patients with severe asthma. CSL311 potently reduced lung neutrophils, eosinophils, and interstitial macrophages and improved airway pathology and lung function in the acute steroid-resistant house dust mite extract model. Chronic intranasal ASP exposure induced airway inflammation and fibrosis and impaired lung function that was inhibited by CSL311. CSL311 normalized the ASP-induced fibrosis-associated extracellular matrix gene expression network and strongly reduced signatures of cellular inflammation in the lung. CONCLUSIONS: ßc cytokines drive steroid-resistant mixed myeloid cell airway inflammation and fibrosis. The anti-ßc antibody CSL311 effectively inhibits mixed T2/neutrophilic inflammation and severe asthma-like pathology and reverses fibrosis gene signatures induced by exposure to commonly encountered environmental allergens.


Asunto(s)
Asma , Receptores de Citocinas , Ratones , Animales , Humanos , Receptores de Citocinas/metabolismo , Remodelación de las Vías Aéreas (Respiratorias) , Pulmón , Citocinas/metabolismo , Ratones Transgénicos , Inflamación , Alérgenos , Esteroides/uso terapéutico , Fibrosis , Pyroglyphidae
7.
J Psycholinguist Res ; 53(1): 14, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38353875

RESUMEN

The aim of this study is to discuss the need for improved intercultural communicative competence (ICC) training for pre-service Chinese as a Second Language (CSL) teachers who travel abroad to teach. Previous studies have shown that pre-service CSL teachers often struggle with intercultural communication, and this study investigates the reasons behind their difficulties and suggests ways to address them. The researchers used the Intercultural Sensitivity Scale (ISS) and the Intercultural Effectiveness Scale (IES) to measure the ICC of 217 pre-service CSL teachers. The study found that while pre-service CSL teachers have strong intercultural communicative emotional ability, their behavioral ability in intercultural communication is weak. In particular, they lacked skills in interactive control, interactive relaxation, identity management, information skills, and behavioral flexibility. The study proposes several strategies to improve ICC training for pre-service CSL teachers. One potential approach is the use of Computer Assisted Language Learning to provide teacher-trainee students with opportunities to practice intercultural communication skills in simulated contexts, receive personalized feedback, and engage with authentic materials and cultural information relevant to their host country. CALL could also facilitate communication between pre-service CSL teachers and former CSL teachers, providing a platform for information exchange and additional psychological support. The study also suggests that pre-service training should distinguish between foreign language learning and intercultural communication skills training. Specifically, it recommends that foreign language proficiency should be improved, while training should focus on educational culture and work culture in the host country, rather than providing a general introduction to the national conditions of the country. Finally, the study proposes that pre-service training should establish contact between pre-service CSL teachers and former CSL teachers as early as possible so that trainees can learn specific relevant information in advance, which can help them get ready, avoid intercultural communication mistakes, and obtain additional psychological support. By incorporating CALL and addressing the areas of weakness identified in the study, pre-service CSL teachers can be better prepared to navigate the challenges of intercultural communication and provide effective and culturally sensitive instruction abroad.


Asunto(s)
Comunicación , Lenguaje , Humanos , Desarrollo del Lenguaje , Aprendizaje , Personal Docente
8.
Development ; 147(18)2020 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-32839181

RESUMEN

During animal development, ligand binding releases the intracellular domain of LIN-12/Notch by proteolytic cleavage to translocate to the nucleus, where it associates with the DNA-binding protein LAG-1/CSL to activate target gene transcription. We investigated the spatiotemporal regulation of LAG-1/CSL expression in Caenorhabditis elegans and observed that an increase in endogenous LAG-1 levels correlates with LIN-12/Notch activation in different cell contexts during reproductive system development. We show that this increase is via transcriptional upregulation by creating a synthetic endogenous operon, and identified an enhancer region that contains multiple LAG-1 binding sites (LBSs) embedded in a more extensively conserved high occupancy target (HOT) region. We show that these LBSs are necessary for upregulation in response to LIN-12/Notch activity, indicating that lag-1 engages in direct positive autoregulation. Deletion of the HOT region from endogenous lag-1 reduced LAG-1 levels and abrogated positive autoregulation, but did not cause hallmark cell fate transformations associated with loss of lin-12/Notch or lag-1 activity. Instead, later somatic reproductive system defects suggest that proper transcriptional regulation of lag-1 confers robustness to somatic reproductive system development.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Proteínas de Unión al ADN/genética , Genitales/crecimiento & desarrollo , Homeostasis/genética , Receptores Notch/genética , Animales , Sitios de Unión/genética , Regulación de la Expresión Génica/genética , Transducción de Señal/genética , Transcripción Genética/genética , Regulación hacia Arriba/genética
9.
Skin Res Technol ; 29(9): e13454, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37753695

RESUMEN

BACKGROUND: Evidence suggests that sebum content is important in skin disorders such as acne. However, sebum levels change depending on the external environment, and quantifying skin sebum levels is challenging. Here, we propose an optimal method for quantifying the facial sebum level. MATERIALS AND METHODS: Four hundred and sixty participants (160 males and 300 females) aged 20-40 were enrolled in this study. A Sebumeter SM 810 was used to measure the sebum level at five facial locations: the forehead, the chin, the left cheek, the right cheek, and the nose. The participants were divided into two groups; one group underwent a one-time measurement (n = 390, male: female = 120: 270), and the other underwent three consecutive measurements (n = 70, male: female = 40: 30). The casual sebum level (CSL) was measured in all patients after a 30-min acclimatization; subsequently, the sebum removal process was conducted, followed by a resting period of 1 h to determine the sebum excretion rate (SER). Spearman's correlation analysis and the Wilcoxon signed-rank test were used to compare the sebum level consistency and differences between the groups. RESULTS: Although three consecutive measurements better reflected the sebum content, the one-time measurement also represented the relative sebum level. One hour after sebum removal, the sebum level recovered to 70%-90%; thus, this method was applicable for use in SER quantification. Of the five testing points, the sebum content was highest in the nose and lowest in the cheeks (both left and right). In addition, the cheeks were the most stable sites in terms of testing points, testing times, and CSL/SER values. A one-time measurement of the CSL could represent the SER 1 h after the sebum removal. In our cohort, the sebum level of males with oily skin was decreased at age 32-35, and that of males with non-oily skin increased at 28-35. The opposite trend was observed in female participants. CONCLUSION: Sebum measurement methods were assessed, including testing times, indices (interval of time) and sites in a conditioned external environment. A one-time measurement of the CSL 1 h after sebum removal was sufficient to determine the sebum level and SER, and the cheeks are recommended as the testing site. Sex and skin type differences were observed in sebum level changes with age.


Asunto(s)
Cara , Sebo , Humanos , Femenino , Masculino , Adulto , Mejilla , Nariz , Frente
10.
Biochem J ; 479(9): 1007-1030, 2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35470373

RESUMEN

Human Complement Receptor 1 (HuCR1) is a potent membrane-bound regulator of complement both in vitro and in vivo, acting via interaction with its ligands C3b and C4b. Soluble versions of HuCR1 have been described such as TP10, the recombinant full-length extracellular domain, and more recently CSL040, a truncated version lacking the C-terminal long homologous repeat domain D (LHR-D). However, the role of N-linked glycosylation in determining its pharmacokinetic (PK) and pharmacodynamic (PD) properties is only partly understood. We demonstrated a relationship between the asialo-N-glycan levels of CSL040 and its PK/PD properties in rats and non-human primates (NHPs), using recombinant CSL040 preparations with varying asialo-N-glycan levels. The clearance mechanism likely involves the asialoglycoprotein receptor (ASGR), as clearance of CSL040 with a high proportion of asialo-N-glycans was attenuated in vivo by co-administration of rats with asialofetuin, which saturates the ASGR. Biodistribution studies also showed CSL040 localization to the liver following systemic administration. Our studies uncovered differential PD effects by CSL040 on complement pathways, with extended inhibition in both rats and NHPs of the alternative pathway compared with the classical and lectin pathways that were not correlated with its PK profile. Further studies showed that this effect was dose dependent and observed with both CSL040 and the full-length extracellular domain of HuCR1. Taken together, our data suggests that sialylation optimization is an important consideration for developing HuCR1-based therapeutic candidates such as CSL040 with improved PK properties and shows that CSL040 has superior PK/PD responses compared with full-length soluble HuCR1.


Asunto(s)
Lectinas , Polisacáridos , Animales , Complemento C3b/metabolismo , Complemento C4b/metabolismo , Glicosilación , Lectinas/metabolismo , Ratas , Receptores de Complemento/metabolismo , Receptores de Complemento 3b/metabolismo , Distribución Tisular
11.
Entropy (Basel) ; 25(2)2023 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-36832661

RESUMEN

Models of dynamical wave function collapse consistently describe the breakdown of the quantum superposition with the growing mass of the system by introducing non-linear and stochastic modifications to the standard Schrödinger dynamics. Among them, Continuous Spontaneous Localization (CSL) was extensively investigated both theoretically and experimentally. Measurable consequences of the collapse phenomenon depend on different combinations of the phenomenological parameters of the model-the strength λ and the correlation length rC-and have led, so far, to the exclusion of regions of the admissible (λ-rC) parameters space. We developed a novel approach to disentangle the λ and rC probability density functions, which discloses a more profound statistical insight.

12.
J Biol Chem ; 296: 100200, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33334893

RESUMEN

Human complement receptor 1 (HuCR1) is a pivotal regulator of complement activity, acting on all three complement pathways as a membrane-bound receptor of C3b/C4b, C3/C5 convertase decay accelerator, and cofactor for factor I-mediated cleavage of C3b and C4b. In this study, we sought to identify a minimal soluble fragment of HuCR1, which retains the complement regulatory activity of the wildtype protein. To this end, we generated recombinant, soluble, and truncated versions of HuCR1 and compared their ability to inhibit complement activation in vitro using multiple assays. A soluble form of HuCR1, truncated at amino acid 1392 and designated CSL040, was found to be a more potent inhibitor than all other truncation variants tested. CSL040 retained its affinity to both C3b and C4b as well as its cleavage and decay acceleration activity and was found to be stable under a range of buffer conditions. Pharmacokinetic studies in mice demonstrated that the level of sialylation is a major determinant of CSL040 clearance in vivo. CSL040 also showed an improved pharmacokinetic profile compared with the full extracellular domain of HuCR1. The in vivo effects of CSL040 on acute complement-mediated kidney damage were tested in an attenuated passive antiglomerular basement membrane antibody-induced glomerulonephritis model. In this model, CSL040 at 20 and 60 mg/kg significantly attenuated kidney damage at 24 h, with significant reductions in cellular infiltrates and urine albumin, consistent with protection from kidney damage. CSL040 thus represents a potential therapeutic candidate for the treatment of complement-mediated disorders.


Asunto(s)
Activación de Complemento , Receptores de Complemento 3b/inmunología , Animales , Línea Celular , Complemento C3b/inmunología , Complemento C4b/inmunología , Femenino , Glomerulonefritis/inmunología , Glomerulonefritis/terapia , Humanos , Ratones , Ratones Endogámicos C57BL , Receptores de Complemento 3b/química , Receptores de Complemento 3b/uso terapéutico , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/uso terapéutico
13.
Biochem Biophys Res Commun ; 627: 39-44, 2022 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-36007333

RESUMEN

NaV1.5 channel is an integral membrane protein involved in the initiation and conduction of action potentials. IQ motif is located in the C-terminal domain of NaV1.5 sodium channel, which is highly conserved in human sodium channel subtypes. IQ motif is involved in the Ca2+-dependent regulation through interaction with the regulatory proteins such as calpastatin domain L (CSL). Mutations in SCN5A, the gene encoding NaV1.5 channel, have been linked to many cardiac arrhythmias, such as Long QT syndrome type 3 (LQT3) and Brugada syndrome (BRS). LQT3-associated mutations in NaV1.5 IQ motif, IQQ1909R and IQR1913H, have been reported to affect the late INa. A BRS-associated mutation in NaV1.5 IQ motif, IQA1924T, has been reported to affect the peak INa. But the detailed pathogenic mechanisms of LQT3 and BRS remains unclear. To explore the binding properties of CSL to IQ motif and its muants associated with LQT3/BRS, molecular docking and GST pull down assay were performed in this study. As a result, S58 and E59 in CSL activating channel effect region L54-64 were involved in the conformation of the CSL/IQWT complex by protein-protein docking. IQ motif could bind to CSL in a [CSL]-dependent and [Ca2+]-dependent manner by pull down assay. However, the binding affinities of IQQ1909R and IQR1913H to CSL were decreased and its reaction rates with CSL were slower. The binding characteristics of IQA1924T to CSL was opposite in a [Ca2+]-dependent manner and its binding efficacy became smaller. The changes of the binding characteristics of IQmutants to CSL would affect the regulation of NaV1.5 channel, which may be related to LQT3 and BRS.


Asunto(s)
Síndrome de Brugada , Síndrome de QT Prolongado , Síndrome de Brugada/genética , Proteínas de Unión al Calcio/genética , Humanos , Síndrome de QT Prolongado/genética , Simulación del Acoplamiento Molecular , Mutación , Canal de Sodio Activado por Voltaje NAV1.5/metabolismo , Canales de Sodio/genética
14.
Sensors (Basel) ; 22(20)2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36298150

RESUMEN

The traditional pointer instrument recognition scheme is implemented in three steps, which is cumbersome and inefficient. So it is difficult to apply to the industrial production of real-time monitoring. Based on the improvement of the CSL coding method and the setting of the pre-cache mechanism, an intelligent reading recognition technology of the YOLOv5 pointer instrument is proposed in this paper, which realizes the rapid positioning and reading recognition of the pointer instrument. The problem of angle interaction in rotating target detection is eliminated, the complexity of image preprocessing is avoided, and the problems of poor adaptability of Hough detection are solved in this strategy. The experimental results show that compared with the traditional algorithm, the algorithm in this paper can effectively identify the angle of the pointer instrument, has high detection efficiency and strong adaptability, and has broad application prospects.

15.
Int J Mol Sci ; 23(20)2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36293193

RESUMEN

The primary role of Notch is to specify cellular identities, whereby the cells respond to amazingly small changes in Notch signalling activity. Hence, dosage of Notch components is crucial to regulation. Central to Notch signal transduction are CSL proteins: together with respective cofactors, they mediate the activation or the silencing of Notch target genes. CSL proteins are extremely similar amongst species regarding sequence and structure. We noticed that the fly homologue suppressor of hairless (Su(H)) is stabilised in transcription complexes. Using specific transgenic fly lines and HeLa RBPJKO cells we provide evidence that Su(H) is subjected to proteasomal degradation with a half-life of about two hours if not protected by binding to co-repressor hairless or co-activator Notch. Moreover, Su(H) stability is controlled by MAPK-dependent phosphorylation, matching earlier data for RBPJ in human cells. The homologous murine and human RBPJ proteins, however, are largely resistant to degradation in our system. Mutating presumptive protein contact sites, however, sensitised RBPJ for proteolysis. Overall, our data highlight the similarities in the regulation of CSL protein stability across species and imply that turnover of CSL proteins may be a conserved means of regulating Notch signalling output directly at the level of transcription.


Asunto(s)
Proteínas de Drosophila , Humanos , Animales , Ratones , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas Co-Represoras/metabolismo , Receptores Notch/metabolismo , Fosforilación , Proteínas Represoras/metabolismo , Unión Proteica
16.
Toxicol Appl Pharmacol ; 422: 115557, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33932462

RESUMEN

CSL112 (apolipoprotein A-I, apo AI [human]) is an investigational drug in Phase 3 development for risk reduction of early recurrent cardiovascular events following an acute myocardial infarction (AMI). Although CSL112 is known to be well tolerated with a regimen of four weekly 6 g intravenous infusions after AMI, high doses of reconstituted apo AI preparations can transiently elevate liver enzymes in rats, raising the possibility of additive liver toxicity and toxicokinetic (TK) effects upon co-administration with cholesterol-lowering drugs, i.e., HMG-CoA reductase and proprotein convertase subtilisin/kexin type 9 inhibitors. We performed a toxicity and TK study in CD rats assigned to eleven treatment groups, including two dose levels of intravenous (IV) CSL112 (140 mg/kg, low-dose; 600 mg/kg, high-dose) administered as a single dose, alone or with intravenous alirocumab 50 mg/kg/week and/or oral atorvastatin 10 mg/kg/day. In addition, control groups of atorvastatin and alirocumab alone and in combination were investigated. Results showed some liver enzyme elevations (remaining <2-fold of baseline) related to administration of CSL112 alone. There was limited evidence of an additive effect of CSL112 on liver enzymes when combined, at either dose level, with alirocumab and/or atorvastatin, and histology revealed no evidence of an increased incidence or severity of hepatocyte vacuolation compared to the control treatments. Co-administration of the study drugs had minimal effect on their respective exposure levels, and on levels of total cholesterol and high-density lipoprotein cholesterol. These data support concomitant use of CSL112 with alirocumab and/or atorvastatin with no anticipated negative impact on liver safety and TK.


Asunto(s)
Anticuerpos Monoclonales Humanizados/toxicidad , Anticolesterolemiantes/toxicidad , Atorvastatina/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Lipoproteínas HDL/toxicidad , Hígado/efectos de los fármacos , Animales , Anticuerpos Monoclonales Humanizados/farmacocinética , Anticolesterolemiantes/farmacocinética , Atorvastatina/farmacocinética , Biomarcadores/sangre , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Colesterol/sangre , Interacciones Farmacológicas , Femenino , Lipoproteínas HDL/farmacocinética , Hígado/metabolismo , Hígado/patología , Masculino , Ratas Sprague-Dawley , Medición de Riesgo , Pruebas de Toxicidad , Toxicocinética
17.
Glycoconj J ; 38(4): 509-516, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34146213

RESUMEN

Physiological role of a core fucose specific lectin from Cephalosporium curvulum isolated from mycotic keratitis patient in mediating pathogenesis was reported earlier. CSL has opposite effects on HCECs, at the initiation of infection when lectin concentration is low, CSL induces proinflammatory response and at higher concentration it inhibits growth as the infection progresses. Here we delineate detailed mechanism of opposing effects of CSL by confirming the binding of CSL and anti TLR 2 and 4 antibodies to TLRs 2 and 4 purified from HCECs using Galectin-3 Sepharose 4B column. Further, the expression of signaling proteins were monitored by Western blotting and apoptosis assay. At concentration of 0.3 µg/ml, CSL induced the activation of TLR-2,-4 and adapter protein MyD88. CSL also induced the expression of transcription factors NFkB, C-Jun and proinflammatory cytokines like interleukins -6 and -8 essential in maintaining cell proliferation. In contrast at higher concentrations i.e. 5 µg/ml CSL induces apoptotic effect as evidenced by increase in early and late apoptotic population as demonstrated by Annexin V-PI assay. Western blotting revealed that CSL treated HCECs at higher concentration lead to MyD88 dependent expression of apoptotic proteins like FADD, Caspase -8 and -3. All these results are in line with and substantiate our earlier results that indeed CSL is involved in mediating host pathogen interactions by interacting with cell surface TLRs, activating downstream signaling pathways leading to pathogenesis. Findings are of clinical significance in developing carbohydrate based therapeutic strategy to control infection and the disease.


Asunto(s)
Acremonium/metabolismo , Células Epiteliales/efectos de los fármacos , Epitelio Corneal/citología , Queratitis/microbiología , Lectinas/toxicidad , Apoptosis , Línea Celular , Proliferación Celular , Humanos , Queratitis/patología , Lectinas/inmunología , Factor 88 de Diferenciación Mieloide
18.
Hereditas ; 158(1): 11, 2021 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-33775255

RESUMEN

CSL transcription factors are central to signal transduction in the highly conserved Notch signaling pathway. CSL acts as a molecular switch: depending on the cofactors recruited, CSL induces either activation or repression of Notch target genes. Unexpectedly, CSL depends on its cofactors for nuclear entry, despite its role as gene regulator. In Drosophila, the CSL homologue Suppressor of Hairless (Su(H)), recruits Hairless (H) for repressor complex assembly, and eventually for nuclear import. We recently found that Su(H) is subjected to a dynamic nucleo-cytoplasmic shuttling, thereby strictly following H subcellular distribution. Hence, regulation of nuclear availability of Su(H) by H may represent a new layer of control of Notch signaling activity. Here we extended this work on the murine CSL homologue RBPJ. Using a 'murinized' fly model bearing RBPJwt in place of Su(H) at the endogenous locus we demonstrate that RBPJ protein likewise follows H subcellular distribution. For example, overexpression of a H*NLS3 protein variant defective of nuclear import resulted in a cytosolic localization of RBPJ protein, whereas the overexpression of a H*NES protein variant defective in the nuclear export signal caused the accumulation of RBPJ protein in the nucleus. Evidently, RBPJ is exported from the nucleus as well. Overall these data demonstrate that in our fly model, RBPJ is subjected to H-mediated nucleo-cytoplasmic shuttling as is Su(H). These data raise the possibility that nuclear availability of mammalian CSL proteins is likewise restricted by cofactors, and may hence present a more general mode of regulating Notch signaling activity.


Asunto(s)
Proteínas de Drosophila/genética , Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/genética , Proteínas Represoras/genética , Transporte Activo de Núcleo Celular , Animales , Animales Modificados Genéticamente , Citoplasma , Drosophila melanogaster/genética , Ratones , Receptores Notch/genética , Transducción de Señal
19.
Aesthetic Plast Surg ; 45(5): 2280-2286, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33876285

RESUMEN

BACKGROUND AND AIM: Surgical procedures involving the manipulation of the airway structure have the potential to affect the quality of voice by changing the resonance properties. Regarding this, the present study was conducted to investigate the effect of rhinoplasty on the voice of professional voice users. METHODS AND MATERIALS: This cohort study was conducted on 30 professional voice users. For the purpose of the study, the patients completed the Voice Handicap Index (VHI). In addition, they were subjected to voice analysis that included the measurement of nasality in speech production (i.e., nasalance), using the nasometer II. Computerized speech lab was also utilized to examine vowels /e/ and /a/, each of which was sustained for 5 sec by the participants. RESULTS: The mean VHI scores were 8.5 ± 1.98 and 7.36 ± 1.71 before and after the surgery, respectively, indicating no significant difference between the two investigated stages (Z = - 0.53, P = 0.59). However, there was a significant difference between the patients with and without preoperative obstruction in terms of the VHI score (χ2 = 11.06, P = 0.004). With regard to orality, it had the mean values of 16.86 ± 7.45 and 15.22 ± 7.37 before and after the surgery, respectively. Furthermore, the mean values of nasality at the pre- and post-operation stages were 59.42 ± 6.04 and 56.28 ± 10.07, respectively. The comparison between the pre- and post-surgical orality and nasality revealed no significant difference (t = 1.226, P = 0.23 and t = 0.93, P = 0.36, respectively). CONCLUSION: Although rhinoplasty is supposed to affect voice and vocal resonation, the induced changes are not problematic for the professional voice users. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Rinoplastia , Estudios de Cohortes , Humanos , Nariz , Rinoplastia/efectos adversos
20.
Molecules ; 26(14)2021 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-34299608

RESUMEN

The wall is the last frontier of a plant cell involved in modulating growth, development and defense against biotic stresses. Cellulose and additional polysaccharides of plant cell walls are the most abundant biopolymers on earth, having increased in economic value and thereby attracted significant interest in biotechnology. Cellulose biosynthesis constitutes a highly complicated process relying on the formation of cellulose synthase complexes. Cellulose synthase (CesA) and Cellulose synthase-like (Csl) genes encode enzymes that synthesize cellulose and most hemicellulosic polysaccharides. Arabidopsis and rice are invaluable genetic models and reliable representatives of land plants to comprehend cell wall synthesis. During the past two decades, enormous research progress has been made to understand the mechanisms of cellulose synthesis and construction of the plant cell wall. A plethora of cesa and csl mutants have been characterized, providing functional insights into individual protein isoforms. Recent structural studies have uncovered the mode of CesA assembly and the dynamics of cellulose production. Genetics and structural biology have generated new knowledge and have accelerated the pace of discovery in this field, ultimately opening perspectives towards cellulose synthesis manipulation. This review provides an overview of the major breakthroughs gathering previous and recent genetic and structural advancements, focusing on the function of CesA and Csl catalytic domain in plants.


Asunto(s)
Glucosiltransferasas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Dominio Catalítico , Glucosiltransferasas/química , Glucosiltransferasas/genética , Modelos Moleculares , Mutación , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas/química , Plantas/genética
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