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1.
J Am Chem Soc ; 146(13): 9444-9454, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38513075

RESUMEN

The 3d transition metal-catalyzed enantioconvergent radical cross-coupling provides a powerful tool for chiral molecule synthesis. In the classic mechanism, the bond formation relies on the interaction between nucleophile-sequestered metal complexes and radicals, limiting the nucleophile scope to sterically uncongested ones. The coupling of sterically congested nucleophiles poses a significant challenge due to difficulties in transmetalation, restricting the reaction generality. Here, we describe a probable outer-sphere nucleophilic attack mechanism that circumvents the challenging transmetalation associated with sterically congested nucleophiles. This strategy enables a general copper-catalyzed enantioconvergent radical N-alkylation of aromatic amines with secondary/tertiary alkyl halides and exhibits catalyst-controlled stereoselectivity. It accommodates diverse aromatic amines, especially bulky secondary and primary ones to deliver value-added chiral amines (>110 examples). It is expected to inspire the coupling of more nucleophiles, particularly challenging sterically congested ones, and accelerate reaction generality.

2.
Genet Med ; 26(6): 101124, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38522067

RESUMEN

PURPOSE: Germline variant interpretation often depends on population-matched control cohorts. This is not feasible for population groups that are underrepresented in current population reference databases. METHODS: We classify germline variants with population-matched controls for 2 ancestrally diverse cohorts of patients: 132 early-onset or familial colorectal carcinoma patients from Singapore and 100 early-onset colorectal carcinoma patients from the United States. The effects of using a population-mismatched control cohort are simulated by swapping the control cohorts used for each patient cohort, with or without the popmax computational strategy. RESULTS: Population-matched classifications revealed a combined 62 pathogenic or likely pathogenic (P/LP) variants in 34 genes across both cohorts. Using a population-mismatched control cohort resulted in misclassification of non-P/LP variants as P/LP, driven by the absence of ancestry-specific rare variants in the control cohort. Popmax was more effective in alleviating misclassifications for the Singapore cohort than the US cohort. CONCLUSION: Underrepresented population groups can suffer from higher rates of false-positive P/LP results. Popmax can partially alleviate these misclassifications, but its efficacy still depends on the degree with which the population groups are represented in the control cohort.


Asunto(s)
Neoplasias Colorrectales , Mutación de Línea Germinal , Humanos , Mutación de Línea Germinal/genética , Singapur , Neoplasias Colorrectales/genética , Estados Unidos , Estudios de Cohortes , Masculino , Femenino , Predisposición Genética a la Enfermedad , Genética de Población/métodos , Estudios de Casos y Controles , Grupos Minoritarios , Bases de Datos Genéticas
3.
Hum Genomics ; 17(1): 66, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37461096

RESUMEN

BACKGROUND: Cancer predisposition is most often studied in the context of single cancers. However, inherited cancer predispositions can also give rise to multiple primary cancers. Yet, there is a paucity of studies on genetic predisposition in multiple primary cancers, especially those outside of well-defined cancer predisposition syndromes. This study aimed to identify germline variants associated with dual primary cancers of the breast and lung. METHODS: Exome sequencing was performed on germline DNA from 55 Singapore patients (52 [95%] never-smokers) with dual primaries in the breast and lung, confirmed by histopathology. Using two large control cohorts: the local SG10K_Health (n = 9770) and gnomAD non-cancer East Asians (n = 9626); and two additional local case cohorts of early-onset or familial breast cancer (n = 290), and lung cancer (n = 209), variants were assessed for pathogenicity in accordance with ACMG/AMP guidelines. In particular, comparisons were made with known pathogenic or likely pathogenic variants in the ClinVar database, pathogenicity predictions were obtained from in silico prediction software, and case-control association analyses were performed. RESULTS: Altogether, we identified 19 pathogenic or likely pathogenic variants from 16 genes, detected in 17 of 55 (31%) patients. Six of the 19 variants were identified using ClinVar, while 13 variants were classified pathogenic or likely pathogenic using ACMG/AMP guidelines. The 16 genes include well-known cancer predisposition genes such as BRCA2, TP53, and RAD51D; but also lesser known cancer genes EXT2, WWOX, GATA2, and GPC3. Most of these genes are involved in DNA damage repair, reaffirming the role of impaired DNA repair mechanisms in the development of multiple malignancies. These variants warrant further investigations in additional populations. CONCLUSIONS: We have identified both known and novel variants significantly enriched in patients with primary breast and lung malignancies, expanding the body of known cancer predisposition variants for both breast and lung cancer. These variants are mostly from genes involved in DNA repair, affirming the role of impaired DNA repair in the predisposition and development of multiple cancers.


Asunto(s)
Neoplasias de la Mama , Neoplasias Pulmonares , Neoplasias Primarias Múltiples , Humanos , Femenino , Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal/genética , Neoplasias Primarias Múltiples/genética , Neoplasias Pulmonares/genética , Células Germinativas , Glipicanos/genética
4.
Nanotechnology ; 35(36)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38865988

RESUMEN

Reactive oxygen species (ROS) play important roles in regulating various physiological functions in the human body, however, excessive ROS can cause serious damage to the human body, considering the various limitations of natural enzymes as scavengers of ROS in the body, the development of better materials for the scavenging of ROS is of great significance to the biomedical field, and nanozymes, as a kind of nanomaterials which can show the activity of natural enzymes. Have a good potential for the development in the area of ROS scavenging. Metal-organic frameworks (MOFs), which are porous crystalline materials with a periodic network structure composed of metal nodes and organic ligands, have been developed with a variety of active nanozymes including catalase-like, superoxide dismutase-like, and glutathione peroxidase-like enzymes due to the adjustability of active sites, structural diversity, excellent biocompatibility, and they have shown a wide range of applications and prospects. In the present review, we first introduce three representative natural enzymes for ROS scavenging in the human body, methods for the detection of relevant enzyme-like activities and mechanisms of enzyme-like clearance are discussed, meanwhile, we systematically summarize the progress of the research on MOF-based nanozymes, including the design strategy, mechanism of action, and medical application, etc. Finally, the current challenges of MOF-based nanozymes are summarized, and the future development direction is anticipated. We hope that this review can contribute to the research of MOF-based nanozymes in the medical field related to the scavenging of ROS.


Asunto(s)
Estructuras Metalorgánicas , Especies Reactivas de Oxígeno , Estructuras Metalorgánicas/química , Especies Reactivas de Oxígeno/metabolismo , Humanos , Depuradores de Radicales Libres/química , Nanoestructuras/química , Catalasa/química , Catalasa/metabolismo , Animales , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/química
5.
Appl Microbiol Biotechnol ; 108(1): 16, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38170318

RESUMEN

Penicillium fungi, including Penicillium oxalicum, can secrete a range of efficient plant-polysaccharide-degrading enzymes (PPDEs) that is very useful for sustainable bioproduction, using renewable plant biomass as feedstock. However, the low efficiency and high cost of PPDE production seriously hamper the industrialization of processes based on PPDEs. In Penicillium, the expression of PPDE genes is strictly regulated by a complex regulatory system and molecular breeding to modify this system is a promising way to improve fungal PPDE yields. In this mini-review, we present an update on recent research progress concerning PPDE distribution and function, the regulatory mechanism of PPDE biosynthesis, and molecular breeding to produce PPDE-hyperproducing Penicillium strains. This review will facilitate future development of fungal PPDE production through metabolic engineering and synthetic biology, thereby promoting PPDE industrial biorefinery applications. KEY POINTS: • This mini review summarizes PPDE distribution and function in Penicillium. • It updates progress on the regulatory mechanism of PPDE biosynthesis in Penicillium. • It updates progress on breeding of PPDE-hyperproducing Penicillium strains.


Asunto(s)
Penicillium , Polisacáridos/metabolismo
6.
Appl Environ Microbiol ; 89(6): e0036023, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37191516

RESUMEN

Penicillium oxalicum produces an integrated, extracellular cellulase and xylanase system, strictly regulated by several transcription factors. However, the understanding of the regulatory mechanism of cellulase and xylanase biosynthesis in P. oxalicum is limited, particularly under solid-state fermentation (SSF) conditions. In our study, deletion of a novel gene, cxrD (cellulolytic and xylanolytic regulator D), resulted in 49.3 to 2,230% enhanced production of cellulase and xylanase, except for 75.0% less xylanase at 2 days, compared with the P. oxalicum parental strain, when cultured on solid medium containing wheat bran plus rice straw for 2 to 4 days after transfer from glucose. In addition, the deletion of cxrD delayed conidiospore formation, leading to 45.1 to 81.8% reduced asexual spore production and altered mycelial accumulation to various extents. Comparative transcriptomics and real-time quantitative reverse transcription-PCR found that CXRD dynamically regulated the expression of major cellulase and xylanase genes and conidiation-regulatory gene brlA under SSF. In vitro electrophoretic mobility shift assays demonstrated that CXRD bound to the promoter regions of these genes. The core DNA sequence 5'-CYGTSW-3' was identified to be specifically bound by CXRD. These findings will contribute to understanding the molecular mechanism of negative regulation of fungal cellulase and xylanase biosynthesis under SSF. IMPORTANCE Application of plant cell wall-degrading enzymes (CWDEs) as catalysts in biorefining of lignocellulosic biomass into bioproducts and biofuels reduces both chemical waste production and carbon footprint. The filamentous fungus Penicillium oxalicum can secrete integrated CWDEs, with potential for industrial application. Solid-state fermentation (SSF), simulating the natural habitat of soil fungi, such as P. oxalicum, is used for CWDE production, but a limited understanding of CWDE biosynthesis hampers the improvement of CWDE yields through synthetic biology. Here, we identified a novel transcription factor CXRD, which negatively regulates the biosynthesis of cellulase and xylanase in P. oxalicum under SSF, providing a potential target for genetic engineering to improve CWDE production.


Asunto(s)
Celulasa , Penicillium , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Fermentación , Celulasa/genética , Celulasa/metabolismo , Regulación Fúngica de la Expresión Génica , Penicillium/metabolismo
7.
Hum Genomics ; 16(1): 61, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36424660

RESUMEN

BACKGROUND: For the majority of individuals with early-onset or familial breast cancer referred for genetic testing, the genetic basis of their familial breast cancer remains unexplained. To identify novel germline variants associated with breast cancer predisposition, whole-exome sequencing (WES) was performed. METHODS: WES on 290 BRCA1/BRCA2-negative Singaporeans with early-onset breast cancer and/or a family history of breast cancer was done. Case-control analysis against the East-Asian subpopulation (EAS) from the Genome Aggregation Database (gnomAD) identified variants enriched in cases, which were further selected by occurrence in cancer gene databases. Variants were further evaluated in repeated case-control analyses using a second case cohort from the database of Genotypes and Phenotypes (dbGaP) comprising 466 early-onset breast cancer patients from the United States, and a Singapore SG10K_Health control cohort. RESULTS: Forty-nine breast cancer-associated germline pathogenic variants in 37 genes were identified in Singapore cases versus gnomAD (EAS). Compared against SG10K_Health controls, 13 of 49 variants remain significantly enriched (False Discovery Rate (FDR)-adjusted p < 0.05). Comparing these 49 variants in dbGaP cases against gnomAD (EAS) and SG10K_Health controls revealed 23 concordant variants that were significantly enriched (FDR-adjusted p < 0.05). Fourteen variants were consistently enriched in breast cancer cases across all comparisons (FDR-adjusted p < 0.05). Seven variants in GPRIN2, NRG1, MYO5A, CLIP1, CUX1, GNAS and MGA were confirmed by Sanger sequencing. CONCLUSIONS: In conclusion, we have identified pathogenic variants in genes associated with breast cancer predisposition. Importantly, many of these variants were significant in a second case cohort from dbGaP, suggesting that the strategy of using case-control analysis to select variants could potentially be utilized for identifying variants associated with cancer susceptibility.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Estados Unidos , Secuenciación del Exoma , Predisposición Genética a la Enfermedad , Genes BRCA2 , Estudios de Casos y Controles
8.
Appl Microbiol Biotechnol ; 107(11): 3605-3620, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37119203

RESUMEN

The filamentous fungus Penicillium oxalicum secretes integrative plant polysaccharide-degrading enzymes (PPDEs) applicable to biotechnology. Glycogen synthase kinase-3ß (GSK-3ß) mediates various cellular processes in eukaryotic cells, but the regulatory mechanisms of PPDE biosynthesis in filamentous fungi remain poorly understood. In this study, POGSK-3ß (POX_c04478), a homolog of GSK-3ß in P. oxalicum, was characterised using biochemical, microbiological and omics approaches. Knockdown of POGSK-3ß in P. oxalicum using a copper-responsive promoter replacement system led to 53.5 - 63.6%, 79.0 - 92.8% and 76.8 - 94.7% decreases in the production of filter paper cellulase, soluble starch-degrading enzyme and raw starch-degrading enzyme, respectively, compared with the parental strain ΔKu70. POGSK-3ß promoted mycelial growth and conidiation. Transcriptomic profiling and real-time quantitative reverse transcription PCR analyses revealed that POGSK-3ß dynamically regulated the expression of genes encoding major PPDEs, as well as fungal development-associated genes. The results broadened our understanding of the regulatory functions of GKS-3ß and provided a promising target for genetic engineering to improve PPDE production in filamentous fungi. KEY POINTS: • The roles of glycogen synthase kinase-3ß were investigated in P. oxalicum. • POGSK-3ß regulated PPDE production, mycelial growth and conidiation. • POGSK-3ß controlled the expression of major PPDE genes and regulatory genes.


Asunto(s)
Polisacáridos Fúngicos , Penicillium , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Polisacáridos Fúngicos/metabolismo , Penicillium/metabolismo , Hongos , Almidón/metabolismo
9.
Graefes Arch Clin Exp Ophthalmol ; 261(4): 1011-1017, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36378338

RESUMEN

BACKGROUND: This study aimed to observe the changes in the ocular surface after phacoemulsification in patients with age-related cataracts with respect to the addition of varying concentrations of hyaluronate. METHODS: Patients with dry eye syndrome were treated with 0.3% and 0.1% sodium hyaluronate eye drops to evaluate the clinical improvement in each treatment group. A total of 73 patients (91 eyes) with age-related cataracts suffering from dry eye syndrome after phacoemulsification were divided into treatment group A (30 eyes), undergoing conventional therapy and treatment with 0.3% sodium hyaluronate; treatment group B (31 eyes), undergoing conventional therapy and treatment with 0.1% sodium hyaluronate; and the control group (group C; 30 eyes), undergoing conventional therapy only. Two groups were given different concentrations of sodium hyaluronate eye drops four times a day (should be completed between 8 AM and 8 PM), one drop at a time. RESULTS: Seven days, 2 weeks, 1 month, and 2 months postoperatively, there were significant differences in the Schirmer I test (SIt), first noninvasive tear film break-up time (NIBUTf), average noninvasive tear film break-up time (NIBUTav), tear meniscus height (TMH), and irregularity (when the refractive force of different parts of different meridians on the same meridian is different. The main manifestation is that the two meridians on the anterior surface of the cornea do not show a 90-degree vertical distribution, which cannot be corrected by conventional astigmatism lenses) between the three groups (p < 0.05). When compared with group C, there were significant differences in the SIt, NIBUTf, NIBUTav, TMH, and irregularity of group A and group B (p < 0.05). When compared with group B, there were significant improvements in the SIt, NIBUTf, NIBUTav, and TMH in group A (p < 0.05). CONCLUSIONS: In the early stage after phacoemulsification, the stability of the tear film is reduced. Adding sodium hyaluronate eye drops can restore tear film structure and improve corneal surface regularity, and a 0.3% solution of sodium hyaluronate eye drops is more effective than a 0.1% solution.


Asunto(s)
Catarata , Síndromes de Ojo Seco , Humanos , Ácido Hialurónico , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/etiología , Lágrimas/química , Soluciones Oftálmicas
10.
Angew Chem Int Ed Engl ; 62(27): e202302983, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37154671

RESUMEN

Transition-metal catalyzed enantioconvergent cross-coupling of tertiary alkyl halides with ammonia offers a rapid avenue to chiral unnatural α,α-disubstituted amino acids. However, the construction of chiral C-N bonds between tertiary-carbon electrophiles and nitrogen nucleophiles presented a great challenge owing to steric congestion. We report a copper-catalyzed enantioconvergent radical C-N cross-coupling of alkyl halides with sulfoximines (as ammonia surrogates) under mild conditions by employing a chiral anionic N,N,N-ligand with a long spreading side arm. An array of α,α-disubstituted amino acid derivatives were obtained with good efficiency and enantioselectivity. The synthetic utility of the strategy has been showcased by the elaboration of the coupling products into different chiral α-fully substituted amine building blocks.

11.
EMBO J ; 37(20)2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30181118

RESUMEN

The osteogenic differentiation of mesenchymal stem cells (MSCs) is governed by multiple mechanisms. Growing evidence indicates that ubiquitin-dependent protein degradation is critical for the differentiation of MSCs and bone formation; however, the function of ubiquitin-specific proteases, the largest subfamily of deubiquitylases, remains unclear. Here, we identify USP34 as a previously unknown regulator of osteogenesis. The expression of USP34 in human MSCs increases after osteogenic induction while depletion of USP34 inhibits osteogenic differentiation. Conditional knockout of Usp34 from MSCs or pre-osteoblasts leads to low bone mass in mice. Deletion of Usp34 also blunts BMP2-induced responses and impairs bone regeneration. Mechanically, we demonstrate that USP34 stabilizes both Smad1 and RUNX2 and that depletion of Smurf1 restores the osteogenic potential of Usp34-deficient MSCs in vitro Taken together, our data indicate that USP34 is required for osteogenic differentiation and bone formation.


Asunto(s)
Proteína Morfogenética Ósea 2/metabolismo , Diferenciación Celular , Células Madre Mesenquimatosas/metabolismo , Osteogénesis , Transducción de Señal , Proteasas Ubiquitina-Específicas/metabolismo , Animales , Proteína Morfogenética Ósea 2/genética , Regeneración Ósea/genética , Técnicas de Silenciamiento del Gen , Humanos , Células Madre Mesenquimatosas/citología , Ratones , Ratones Noqueados , Osteoblastos/citología , Osteoblastos/metabolismo , Proteasas Ubiquitina-Específicas/genética
12.
Nutr Neurosci ; 25(3): 530-536, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32431234

RESUMEN

Objective: To investigate the effect of nutritional support on nutritional status and clinical outcomes of patients with traumatic brain injury (TBI).Methods: Sixty-one patients with TBI from the intensive care unit and neurosurgery of Xianyang Central Hospital from 2017 to 2019 were retrospectively included. General and clinical data of the study subjects were collected. The control group (n = 28) received parenteral nutrition alone, and the observation group (n = 33) received parenteral nutrition combined with enteral nutrition. The general conditions and biochemical indicators of both groups of patients were divided into two groups of ≤8 and ≥9 for stratified analysis to compare the nutritional support status and infection complications during hospitalization Occurrence, ICU length of stay, total length of stay, total cost of stay, and prognostic indicators of the patients were analyzed and compared.Results: There were no significant differences in biochemical indicators between both groups of patients when they were discharged. Among patients with GCS ≤8 points, the incidence of lung infection in the observer was significantly higher than that in the control group (P < 0.001), but the incidence of intracranial infection, stress ulcers, and diarrhea was not statistically different from that in the control group (P = 0.739). No significant differences were observed in hospitalization time and hospitalization costs between both groups (P = 0.306 and P = 0.079, respectively). The observation group was significantly better than the control group in GSC score and long-term quality of life score (P = 0.042 and P = 0.025, respectively). When GCS was ≥ 9 points, there was no statistical difference in the incidence of lung infections and intracranial infections between both groups of patients (P = 0.800 and P = 0.127, respectively). The observation group was significantly higher than the control group in terms of length of hospital stay, nasal feeding time and hospitalization costs (P < 0.001, P < 0.001 and P = 0.006, respectively). The observation group was significantly better than the control group in GSC score and long-term quality of life score (P = 0.001 and P = 0.015, respectively). There was no significant difference in the incidence of pulmonary infection and intracranial infection between both groups of patients (P = 0.800 and P = 0.127, respectively).Conclusion: Enteral nutrition combined with parenteral nutrition intervention has a positive effect on the clinical prognosis of TBI patients.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Calidad de Vida , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/terapia , Nutrición Enteral , Humanos , Nutrición Parenteral , Estudios Retrospectivos
13.
J Am Chem Soc ; 143(37): 15413-15419, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34505516

RESUMEN

α-Chiral alkyl primary amines are virtually universal synthetic precursors for all other α-chiral N-containing compounds ubiquitous in biological, pharmaceutical, and material sciences. The enantioselective amination of common alkyl halides with ammonia is appealing for potential rapid access to α-chiral primary amines, but has hitherto remained rare due to the multifaceted difficulties in using ammonia and the underdeveloped C(sp3)-N coupling. Here we demonstrate sulfoximines as excellent ammonia surrogates for enantioconvergent radical C-N coupling with diverse racemic secondary alkyl halides (>60 examples) by copper catalysis under mild thermal conditions. The reaction efficiently provides highly enantioenriched N-alkyl sulfoximines (up to 99% yield and >99% ee) featuring secondary benzyl, propargyl, α-carbonyl alkyl, and α-cyano alkyl stereocenters. In addition, we have converted the masked α-chiral primary amines thus obtained to various synthetic building blocks, ligands, and drugs possessing α-chiral N-functionalities, such as carbamate, carboxylamide, secondary and tertiary amine, and oxazoline, with commonly seen α-substitution patterns. These results shine light on the potential of enantioconvergent radical cross-coupling as a general chiral carbon-heteroatom formation strategy.

14.
Analyst ; 146(18): 5650-5657, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34378558

RESUMEN

This paper investigates the mechanism of a new acoustic micro-ejector using a Lamb wave transducer array, which can stably generate picoliter (pL) droplet jetting without nozzles. With eight transducers arranged as an octagon array, droplets are ejected based on the mechanism of combined acoustic pressure waves and acoustic streaming. The acoustic focusing area is designed as a line at the liquid center, which is the key factor for a large working range of liquid height. The experimental results show that the ejector can produce uniform water droplets of 22 µm diameter (5.6 pL in volume) continuously at a rate of 0.33 kHz with high ejection stability, owing to a large liquid height window and high acoustic wave frequency. By delivering precise ∼pL droplets without clogging issues, the acoustic ejector has great potential for demanding biochemical applications.


Asunto(s)
Acústica , Sonido , Diseño de Equipo , Transductores , Agua
15.
Appl Microbiol Biotechnol ; 105(2): 661-678, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33409610

RESUMEN

Mitogen-activated protein kinase (MAPK) cascades are broadly conserved and play essential roles in multiple cellular processes, including fungal development, pathogenicity, and secondary metabolism. Their function, however, also exhibits species and strain specificity. Penicillium oxalicum secretes plant-biomass-degrading enzymes (PBDEs) that contribute to the carbon cycle in the natural environment and to utilization of lignocellulose in industrial processes. However, knowledge of the MAPK pathway in P. oxalicum has been relatively limited. In this study, comparative transcriptomic analysis of P. oxalicum, cultured on different carbon sources, found ten putative kinase genes with significantly modified transcriptional levels. Six of these putative kinase genes were knocked out in the parental strain ∆PoxKu70, and deletion of the gene, Fus3/Kss1-like PoxMK1 (POX00158), resulted in the largest reduction (91.1%) in filter paper cellulase production. Further tests revealed that the mutant ∆PoxMK1 lost 37.1 to 92.2% of PBDE production, under both submerged- and solid-state fermentation conditions, compared with ∆PoxKu70. In addition, the mutant ∆PoxMK1 had reduced vegetative growth and increased pigment biosynthesis. Comparative transcriptomic analysis showed that PoxMK1 deletion from P. oxalicum downregulated the expression of major PBDE genes and known regulatory genes such as PoxClrB and PoxCxrB, whereas the transcription of pigment biosynthesis-related genes was upregulated. Comparative phosphoproteomic analysis revealed that PoxMK1 deletion considerably modified phosphorylation of key transcription- and signal transduction-associated proteins, including transcription factors Mcm1 and Atf1, RNA polymerase II subunits Rpb1 and Rpb9, MAPK-associated Hog1 and Ste7, and cyclin-dependent kinase Kin28. These findings provide novel insights into understanding signal transduction and regulation of PBDE gene expression in fungi.Key points• PoxMK1 is involved in expression of PBDE- and pigment synthesis-related genes.• PoxMK1 is required for vegetative growth of P. oxalicum.• PoxMK1 is involved in phosphorylation of key TFs, kinases, and RNA polymerase II.


Asunto(s)
Penicillium , Biomasa , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Proteínas Quinasas Activadas por Mitógenos , Penicillium/genética , Penicillium/metabolismo
16.
Appl Opt ; 60(27): 8466-8471, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34612947

RESUMEN

To simplify the design of a beam scanning device, we present a simple and compact structure to realize the frequency scanning characteristic based on a hybrid waveguide consisting of a spoof surface plasmon polariton (SSPP) transmission line and half-mode substrate integrated waveguide (HMSIW). Additionally, the radiation characteristic is implemented using periodically modulated slots. The scanning angle range covers backward to forward directions without an open stop band at the broadside. The results from both simulations and measurements show that the total scanning angle reaches 117° for a frequency range of 9-11.4 GHz. Owing to the inherent features of the HMSIW and the unique design of the SSPP transmission line, the entire structure is only 139.2mm×15mm in size. Moreover, the average gain is approximately 6.5 dBi. Overall, the compact size and good performance ensure that the proposed design is favorable for planar integrated communication systems.

17.
Appl Opt ; 60(12): 3374-3379, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33983242

RESUMEN

A direct conversion from spoof surface plasmon polaritons (SSPPs) to radiation mode is proposed. A modified parallel two-wire SSPP transmission line is the key to the conversion, which is composed of traditional unit cells with slots among them. Taking advantages of the slots, the phase velocity of electromagnetic waves is larger than that of light, leading to the radiation. Both simulated and measured results show that the radiation occurs from 7.6 to 11 GHz, and the radiation angle keeps nearly stable in the whole operating frequency band, which can be predicted by theoretical calculation. The average gain and efficiency is 6.41 dBi and around 90%, respectively. The simple structure with flexibly tunable operating frequency makes the proposed design promising in planar integrated communication systems.

18.
J Biol Chem ; 294(43): 15781-15794, 2019 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-31488543

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a chronic disease characterized by the pathological remodeling of air sacs as a result of excessive accumulation of extracellular matrix (ECM) proteins, but the mechanism governing the robust protein expression is poorly understood. Our recent findings demonstrate that alternative polyadenylation (APA) caused by NUDT21 reduction is important for the increased expression of fibrotic mediators and ECM proteins in lung fibroblasts by shortening the 3'-untranslated regions (3'-UTRs) of mRNAs and stabilizing their transcripts, therefore activating pathological signaling pathways. Despite the importance of NUDT21 reduction in the regulation of fibrosis, the underlying mechanisms for the depletion are unknown. We demonstrate here that NUDT21 is depleted by TGFß1. We found that miR203, which is increased in IPF, was induced by TGFß1 to target the NUDT21 3'-UTR, thus depleting NUDT21 in human and mouse lung fibroblasts. TGFß1-mediated NUDT21 reduction was attenuated by the miR203 inhibitor antagomiR203 in fibroblasts. TGFß1 transgenic mice revealed that TGFß1 down-regulates NUDT21 in fibroblasts in vivo Furthermore, TGFß1 promoted differential APA of fibrotic genes, including FGF14, RICTOR, TMOD2, and UCP5, in association with increased protein expression. This unique differential APA signature was also observed in IPF fibroblasts. Altogether, our results identified TGFß1 as an APA regulator through NUDT21 depletion amplifying pulmonary fibrosis.


Asunto(s)
Regiones no Traducidas 3'/genética , Pulmón/patología , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Células Cultivadas , Factor de Especificidad de Desdoblamiento y Poliadenilación/genética , Factor de Especificidad de Desdoblamiento y Poliadenilación/metabolismo , Regulación hacia Abajo/genética , Fibroblastos/metabolismo , Fibroblastos/patología , Fibrosis , Humanos , Ratones Endogámicos C57BL , Ratones Transgénicos , MicroARNs/genética , MicroARNs/metabolismo , Modelos Biológicos , Poliadenilación/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
19.
J Am Chem Soc ; 142(20): 9501-9509, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32338510

RESUMEN

A copper-catalyzed intermolecular three-component asymmetric radical 1,2-carboalkynylation of alkenes has been developed, providing straightforward access to diverse chiral alkynes from readily available alkyl halides and terminal alkynes. The utilization of a cinchona alkaloid-derived multidentate N,N,P-ligand is crucial for the efficient radical generation from mildly oxidative precursors by copper and the effective inhibition of the undesired Glaser coupling side reaction. The substrate scope is broad, covering (hetero)aryl-, alkynyl-, and aminocarbonyl-substituted alkenes, (hetero)aryl and alkyl as well as silyl alkynes, and tertiary to primary alkyl radical precursors with excellent functional group compatibility. Facile transformations of the obtained chiral alkynes have also been demonstrated, highlighting the excellent complementarity of this protocol to direct 1,2-dicarbofunctionalization reactions with C(sp2/sp3)-based reagents.

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