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1.
Cell ; 186(17): 3726-3743.e24, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37442136

RESUMEN

Elucidating the cellular organization of the cerebral cortex is critical for understanding brain structure and function. Using large-scale single-nucleus RNA sequencing and spatial transcriptomic analysis of 143 macaque cortical regions, we obtained a comprehensive atlas of 264 transcriptome-defined cortical cell types and mapped their spatial distribution across the entire cortex. We characterized the cortical layer and region preferences of glutamatergic, GABAergic, and non-neuronal cell types, as well as regional differences in cell-type composition and neighborhood complexity. Notably, we discovered a relationship between the regional distribution of various cell types and the region's hierarchical level in the visual and somatosensory systems. Cross-species comparison of transcriptomic data from human, macaque, and mouse cortices further revealed primate-specific cell types that are enriched in layer 4, with their marker genes expressed in a region-dependent manner. Our data provide a cellular and molecular basis for understanding the evolution, development, aging, and pathogenesis of the primate brain.


Asunto(s)
Corteza Cerebral , Macaca , Análisis de la Célula Individual , Transcriptoma , Animales , Humanos , Ratones , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Macaca/metabolismo , Transcriptoma/genética
2.
Cell ; 185(10): 1777-1792.e21, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35512705

RESUMEN

Spatially resolved transcriptomic technologies are promising tools to study complex biological processes such as mammalian embryogenesis. However, the imbalance between resolution, gene capture, and field of view of current methodologies precludes their systematic application to analyze relatively large and three-dimensional mid- and late-gestation embryos. Here, we combined DNA nanoball (DNB)-patterned arrays and in situ RNA capture to create spatial enhanced resolution omics-sequencing (Stereo-seq). We applied Stereo-seq to generate the mouse organogenesis spatiotemporal transcriptomic atlas (MOSTA), which maps with single-cell resolution and high sensitivity the kinetics and directionality of transcriptional variation during mouse organogenesis. We used this information to gain insight into the molecular basis of spatial cell heterogeneity and cell fate specification in developing tissues such as the dorsal midbrain. Our panoramic atlas will facilitate in-depth investigation of longstanding questions concerning normal and abnormal mammalian development.


Asunto(s)
Organogénesis , Transcriptoma , Animales , ADN/genética , Embrión de Mamíferos , Femenino , Perfilación de la Expresión Génica/métodos , Mamíferos/genética , Ratones , Organogénesis/genética , Embarazo , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Transcriptoma/genética
3.
Immunity ; 57(5): 987-1004.e5, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38614090

RESUMEN

The development and function of the immune system are controlled by temporospatial gene expression programs, which are regulated by cis-regulatory elements, chromatin structure, and trans-acting factors. In this study, we cataloged the dynamic histone modifications and chromatin interactions at regulatory regions during T helper (Th) cell differentiation. Our data revealed that the H3K4me1 landscape established by MLL4 in naive CD4+ T cells is critical for restructuring the regulatory interaction network and orchestrating gene expression during the early phase of Th differentiation. GATA3 plays a crucial role in further configuring H3K4me1 modification and the chromatin interaction network during Th2 differentiation. Furthermore, we demonstrated that HSS3-anchored chromatin loops function to restrict the activity of the Th2 locus control region (LCR), thus coordinating the expression of Th2 cytokines. Our results provide insights into the mechanisms of how the interplay between histone modifications, chromatin looping, and trans-acting factors contributes to the differentiation of Th cells.


Asunto(s)
Diferenciación Celular , Cromatina , Código de Histonas , Histonas , Células Th2 , Diferenciación Celular/inmunología , Animales , Cromatina/metabolismo , Ratones , Células Th2/inmunología , Histonas/metabolismo , Factor de Transcripción GATA3/metabolismo , Regulación de la Expresión Génica , Ratones Endogámicos C57BL , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Región de Control de Posición , Citocinas/metabolismo
4.
Immunity ; 56(5): 944-958.e6, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37040761

RESUMEN

Interferon-γ (IFN-γ) is a key cytokine in response to viral or intracellular bacterial infection in mammals. While a number of enhancers are described to promote IFN-γ responses, to the best of our knowledge, no silencers for the Ifng gene have been identified. By examining H3K4me1 histone modification in naive CD4+ T cells within Ifng locus, we identified a silencer (CNS-28) that restrains Ifng expression. Mechanistically, CNS-28 maintains Ifng silence by diminishing enhancer-promoter interactions within Ifng locus in a GATA3-dependent but T-bet-independent manner. Functionally, CNS-28 restrains Ifng transcription in NK cells, CD4+ cells, and CD8+ T cells during both innate and adaptive immune responses. Moreover, CNS-28 deficiency resulted in repressed type 2 responses due to elevated IFN-γ expression, shifting Th1 and Th2 paradigm. Thus, CNS-28 activity ensures immune cell quiescence by cooperating with other regulatory cis elements within the Ifng gene locus to minimize autoimmunity.


Asunto(s)
Linfocitos T CD8-positivos , Interferón gamma , Animales , Interferón gamma/genética , Interferón gamma/metabolismo , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular , Secuencias Reguladoras de Ácidos Nucleicos , Homeostasis , Células TH1 , Mamíferos
5.
Nat Immunol ; 24(10): 1602-1603, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37709987
6.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38377343

RESUMEN

Cis-regulatory elements have an important role in human adaptation to the living environment. However, the lag in population genomic cohort studies and epigenomic studies, hinders the research in the adaptive analysis of cis-regulatory elements in human populations. In this study, we collected 4,013 unrelated individuals and performed a comprehensive analysis of adaptive selection of genome-wide cis-regulatory elements in the Han Chinese. In total, 12.34% of genomic regions are under the influence of adaptive selection, where 1.00% of enhancers and 2.06% of promoters are under positive selection, and 0.06% of enhancers and 0.02% of promoters are under balancing selection. Gene ontology enrichment analysis of these cis-regulatory elements under adaptive selection reveals that many positive selections in the Han Chinese occur in pathways involved in cell-cell adhesion processes, and many balancing selections are related to immune processes. Two classes of adaptive cis-regulatory elements related to cell adhesion were in-depth analyzed, one is the adaptive enhancers derived from neanderthal introgression, leads to lower hyaluronidase level in skin, and brings better performance on UV-radiation resistance to the Han Chinese. Another one is the cis-regulatory elements regulating wound healing, and the results suggest the positive selection inhibits coagulation and promotes angiogenesis and wound healing in the Han Chinese. Finally, we found that many pathogenic alleles, such as risky alleles of type 2 diabetes or schizophrenia, remain in the population due to the hitchhiking effect of positive selections. Our findings will help deepen our understanding of the adaptive evolution of genome regulation in the Han Chinese.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hombre de Neandertal , Humanos , Animales , Diabetes Mellitus Tipo 2/genética , Selección Genética , Secuencias Reguladoras de Ácidos Nucleicos , Regiones Promotoras Genéticas , Hombre de Neandertal/genética , China , Elementos de Facilitación Genéticos
7.
Hum Mol Genet ; 32(22): 3181-3193, 2023 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-37622920

RESUMEN

Prostate cancer (PCa) brings huge public health burden in men. A growing number of conventional observational studies report associations of multiple circulating proteins with PCa risk. However, the existing findings may be subject to incoherent biases of conventional epidemiologic studies. To better characterize their associations, herein, we evaluated associations of genetically predicted concentrations of plasma proteins with PCa risk. We developed comprehensive genetic prediction models for protein levels in plasma. After testing 1308 proteins in 79 194 cases and 61 112 controls of European ancestry included in the consortia of BPC3, CAPS, CRUK, PEGASUS, and PRACTICAL, 24 proteins showed significant associations with PCa risk, including 16 previously reported proteins and eight novel proteins. Of them, 14 proteins showed negative associations and 10 showed positive associations with PCa risk. For 18 of the identified proteins, potential functional somatic changes of encoding genes were detected in PCa patients in The Cancer Genome Atlas (TCGA). Genes encoding these proteins were significantly involved in cancer-related pathways. We further identified drugs targeting the identified proteins, which may serve as candidates for drug repurposing for treating PCa. In conclusion, this study identifies novel protein biomarker candidates for PCa risk, which may provide new perspectives on the etiology of PCa and improve its therapeutic strategies.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/genética , Proteínas Sanguíneas/genética , Biomarcadores de Tumor/genética
8.
Mol Psychiatry ; 29(4): 1153-1162, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38216726

RESUMEN

Specific metabolites have been reported to be potentially associated with Alzheimer's disease (AD) risk. However, the comprehensive understanding of roles of metabolite biomarkers in AD etiology remains elusive. We performed a large AD metabolome-wide association study (MWAS) by developing blood metabolite genetic prediction models. We evaluated associations between genetically predicted levels of metabolites and AD risk in 39,106 clinically diagnosed AD cases, 46,828 proxy AD and related dementia (proxy-ADD) cases, and 401,577 controls. We further conducted analyses to determine microbiome features associated with the detected metabolites and characterize associations between predicted microbiome feature levels and AD risk. We identified fourteen metabolites showing an association with AD risk. Five microbiome features were further identified to be potentially related to associations of five of the metabolites. Our study provides new insights into the etiology of AD that involves blood metabolites and gut microbiome, which warrants further investigation.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Genómica , Metabolómica , Humanos , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Metabolómica/métodos , Biomarcadores/sangre , Femenino , Masculino , Genómica/métodos , Anciano , Metaboloma , Estudio de Asociación del Genoma Completo/métodos , Microbioma Gastrointestinal/fisiología , Microbioma Gastrointestinal/genética , Factores de Riesgo , Persona de Mediana Edad , Estudios de Casos y Controles
9.
Nucleic Acids Res ; 51(12): 6172-6189, 2023 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-37177993

RESUMEN

The spatial folding of eukaryotic genome plays a key role in genome function. We report here that our recently developed method, Hi-TrAC, which specializes in detecting chromatin loops among accessible genomic regions, can detect active sub-TADs with a median size of 100 kb, most of which harbor one or two cell specifically expressed genes and regulatory elements such as super-enhancers organized into nested interaction domains. These active sub-TADs are characterized by highly enriched histone mark H3K4me1 and chromatin-binding proteins, including Cohesin complex. Deletion of selected sub-TAD boundaries have different impacts, such as decreased chromatin interaction and gene expression within the sub-TADs or compromised insulation between the sub-TADs, depending on the specific chromatin environment. We show that knocking down core subunit of the Cohesin complex using shRNAs in human cells or decreasing the H3K4me1 modification by deleting the H3K4 methyltransferase Mll4 gene in mouse Th17 cells disrupted the sub-TADs structure. Our data also suggest that super-enhancers exist as an equilibrium globule structure, while inaccessible chromatin regions exist as a fractal globule structure. In summary, Hi-TrAC serves as a highly sensitive and inexpensive approach to study dynamic changes of active sub-TADs, providing more explicit insights into delicate genome structures and functions.


Asunto(s)
Cromatina , Elementos de Facilitación Genéticos , Técnicas Genéticas , Secuencias Reguladoras de Ácidos Nucleicos , Animales , Humanos , Ratones , Ensamble y Desensamble de Cromatina , Genoma
10.
Nano Lett ; 24(30): 9368-9376, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39013032

RESUMEN

Development of mRNA therapeutics necessitates targeted delivery technology, while the clinically advanced lipid nanoparticles face difficulty for extrahepatic delivery. Herein, we design highly branched poly(ß-amino ester)s (HPAEs) for efficacious organ-selective mRNA delivery through tailoring their chemical compositions and topological structures. Using an "A2+B3+C2" Michael addition platform, a combinatorial library of 219 HPAEs with varied backbone structures, terminal groups, and branching degrees are synthesized. The branched topological structures of HPAEs provide enhanced serum resistance and significantly higher mRNA expression in vivo. The terminal amine structures of HPAEs determine the organ-selectivity of mRNA delivery following systemic administration: morpholine facilitates liver targeting, ethylenediamine favors spleen delivery, while methylpentane enables mRNA delivery to the liver, spleen, and lungs simultaneously. This study represents a comprehensive exploration of the structure-activity relationship governing both the efficiency and organ-selectivity of mRNA delivery by HPAEs, suggesting promising candidates for treating various organ-related diseases.


Asunto(s)
Polímeros , ARN Mensajero , ARN Mensajero/genética , Animales , Humanos , Polímeros/química , Ratones , Nanopartículas/química , Hígado/metabolismo , Bazo/metabolismo , Técnicas de Transferencia de Gen , Pulmón/metabolismo
11.
Nano Lett ; 24(2): 741-747, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38166145

RESUMEN

The emergence of one-dimensional van der Waals heterostructures (1D vdWHs) opens up potential fields with unique properties, but precise synthesis remains a challenge. The utilization of mixed conductive types of carbon nanotubes as templates has imposed restrictions on the investigation of the electrical behavior and interlayer interaction of 1D vdWHs. In this study, we efficiently encapsulated silver iodide in high-purity semiconducting single-walled carbon nanotubes (sSWCNTs), forming 1D AgI@sSWCNT vdWHs. We characterized the semiconductor-metal transition and increased the carrier concentration of individual AgI@sSWCNTs via sensitive dielectric force microscopy and confirmed the results through electrical device tests. The electrical behavior transition was attributed to an interlayer charge transfer, as demonstrated by Kelvin probe force microscopy. Furthermore, we showed that this method of synthesizing 1D heterostructures can be extended to other metal halides. This work opens the door for the further exploration of the electrical properties of 1D vdWHs.

12.
Nano Lett ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39132906

RESUMEN

Probabilistic bits (p-bits) with thermal- and spin torque-induced nondeterministic magnetization switching are promising candidates for performing probabilistic computing. Previously reported spin torque p-bits include volatile low-energy barrier nanomagnets (LBNMs) with spontaneously fluctuating magnetizations and initialization-necessary nonvolatile magnets. However, initialization-free nonvolatile spin torque p-bits are still lacking. Here, we demonstrate moderately thermal stable spin-orbit torque (SOT) p-bits with non-consecutively deposited Pt//Pt/Co/Pt stacks. Backhopping-like (BH) magnetization switching with a wide range current-tunable probability of final up and down magnetization states from 0% to 100% was achieved, regardless of the initial magnetization state, which was attributed to the interplay of SOT and thermal contributions. Integer factorization using such BH-SOT p-bits in zero magnetic field was demonstrated at times that are significantly shorter than those of existing nonvolatile STT or volatile LBNMs p-bits. Our realization of initialization-free and magnetic field-free moderately thermally stable BH-SOT p-bits opens up a new perspective for probabilistic spintronic applications.

13.
Med Res Rev ; 44(5): 1971-2014, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-38515232

RESUMEN

Atropisomerism, an expression of axial chirality caused by limited bond rotation, is a prominent aspect within the field of medicinal chemistry. It has been shown that atropisomers of a wide range of compounds, including established FDA-approved drugs and experimental molecules, display markedly different biological activities. The time-dependent reversal of chirality in atropisomers poses complexity and obstacles in the process of drug discovery and development. Nonetheless, recent progress in understanding atropisomerism and enhanced characterization methods have greatly assisted medicinal chemists in the effective development of atropisomeric drug molecules. This article provides a comprehensive review of their special design thoughts, synthetic routes, and biological activities, serving as a reference for the synthesis and biological evaluation of bioactive atropisomers in the future.


Asunto(s)
Diseño de Fármacos , Descubrimiento de Drogas , Estereoisomerismo , Humanos , Animales
14.
J Am Chem Soc ; 146(12): 8464-8471, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38483268

RESUMEN

One-dimensional (1D) high-entropy compounds (HECs) with subnano diameters are highly attractive because long-range electron delocalization may occur along the high-entropy atomic chain, which results in extraordinary properties. Nevertheless, synthesizing such 1D HECs presents a substantial challenge, and the physicochemical attributes of these novel structures remain ambiguous. Herein, we developed a comelting-filling-freezing-modification (co-MFFM) method for synthesizing 1D high-entropy metal phosphide (HEP) by simultaneously encapsulating various metal cations within single-walled carbon nanotubes (SWCNTs) followed with a phosphorization process. The resulting 1D HEP nanowires confined within SWCNTs exhibit crucial features, including an ultrafine, high-entropy, and amorphous structure, along with a core-shell arrangement. The SWCNT as a shell could donate π electrons to 1D HEP for enhanced electron delocalization and protect 1D HEP as an atomically single-layered protective covering, thus boosting high electrocatalytic activity and stability. Moreover, the co-MFFM method demonstrates scalability for mass production and displays universal applicability to the synthesis of various 1D HECs.

15.
J Neurochem ; 168(2): 83-99, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38183677

RESUMEN

In central nervous system (CNS), demyelination is a pathological process featured with a loss of myelin sheaths around axons, which is responsible for the diseases of multiple sclerosis, neuromyelitis optica, and so on. Transforming growth factor-beta1 (TGF-ß1) is a multifunctional cytokine participating in abundant physiological and pathological processes in CNS. However, the effects of TGF-ß1 on CNS demyelinating disease and its underlying mechanisms are controversial and not well understood. Herein, we evaluated the protective potential of TGF-ß1 in a rodent demyelinating model established by lysophosphatidylcholine (LPC) injection. It was identified that supplement of TGF-ß1 evidently rescued the cognitive deficit and motor dysfunction in LPC modeling mice assessed by novel object recognition and balance beam behavioral tests. Besides, quantified by luxol fast blue staining, immunofluorescence, and western blot, administration of TGF-ß1 was found to significantly ameliorate the demyelinating lesion and reactive astrogliosis by suppressing p38 MAPK pathway. Mechanistically, the results of in vitro experiments indicated that treatment of TGF-ß1 could directly promote the differentiation and migration of cultured oligodendrocytes. Our study revealed that modulating TGF-ß1 activity might serve as a promising and innovative therapeutic strategy in CNS demyelinating diseases.


Asunto(s)
Lesiones Encefálicas , Sustancia Blanca , Animales , Ratones , Gliosis/prevención & control , Inflamación , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Roedores , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Sustancia Blanca/metabolismo
16.
Int J Cancer ; 154(4): 670-678, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37850323

RESUMEN

Genome-wide association studies (GWAS) have identified two dozen genetic variants that are associated with the risk of pancreatic ductal adenocarcinoma (PDAC), a deadly malignancy. However, a majority of these variants are located in noncoding regions of the genome, which limits the translation of GWAS findings into clinical applications. The regulome-wide association study (RWAS) is a recently developed method for identifying TF binding-induced accessibility regions for diseases. However, their potential connection to PDAC has yet to be fully explored. We evaluated the associations between genetically predicted levels of chromatin accessibility and risk of PDAC by using pan-cancer chromatin accessibility genetic prediction models. Our analysis included 8275 cases and 6723 controls from the PanScan (I, II, and III) and PanC4 consortia. To further refine our results, we also integrated genes associated to allele-specific accessibility quantitative trait loci (as-aQTL) and TF motifs located in the as-aQTL. We found that 50 chromatin accessibility features were associated with PDAC risk at a false discovery rate (FDR) of less than 0.05. A total of 28 RWAS peaks were identified as conditionally significant. By integrating the results from as-aQTL, motif analysis, and RWAS, we identified candidate causal regulatory elements for two potential chromatin accessibility regions (THCA_89956 and ESCA_89167) that are associated with PDAC risk. Our study identified chromatin accessibility features in noncoding genomic regions that are associated with PDAC risk. We also predicted the associated genes and disrupt motifs. Our findings provide new insights into the regulatory mechanisms of noncoding regions for pancreatic tumorigenesis.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/métodos , Páncreas , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , Cromatina/genética , Polimorfismo de Nucleótido Simple
17.
Int J Cancer ; 154(5): 852-862, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37860916

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is an uncommon but highly fatal malignancy. Identifying causal metabolite biomarkers offers an opportunity to facilitate effective risk assessment strategies for PDAC. In this study, we performed a two-sample Mendelian randomization (MR) study to characterize the potential causal effects of metabolites in plasma on PDAC risk. Genetic instruments were determined for a total of 506 metabolites from one set of comprehensive genome-wide association studies (GWAS) involving 913 individuals of European ancestry from the INTERVAL/EPIC-Norfolk cohorts. Another set of genetic instruments was developed for 483 metabolites from an independent GWAS conducted with 8299 individuals of European ancestry from the Canadian Longitudinal Study on Aging (CLSA) cohort. We analyzed GWAS data of the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4), comprising 8275 PDAC cases and 6723 controls of European ancestry. The association of metabolites with PDAC risk was assessed using the inverse-variance weighted (IVW) method, and complemented with sensitivity analyses of MR-Egger and MR-PRESSO tests. Potential side effects of targeting the identified metabolites for PDAC intervention were further evaluated by a phenome-wide MR (Phe-MR) analysis. Forty-four unique metabolites were identified to be significantly associated with PDAC risk, of which four top-ranking metabolites (X: 12798, X: 11787, X: 11308 and X: 19141) showed replication evidence when using instruments developed from both two cohorts. Our results highlight novel blood metabolites related to PDAC risk, which may help prioritize metabolic features for PDAC mechanistic research and further evaluation of their potential role in PDAC risk assessment.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Análisis de la Aleatorización Mendeliana , Estudio de Asociación del Genoma Completo , Estudios Longitudinales , Canadá/epidemiología , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética
18.
Mol Microbiol ; 120(6): 830-844, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37800624

RESUMEN

The exopolysaccharide galactosaminogalactan (GAG) contributes to biofilm formation and virulence in the pathogenic fungus Aspergillus fumigatus. Increasing evidence indicates that GAG production is inversely linked with asexual development. However, the mechanisms underlying this regulatory relationship are unclear. In this study, we found that the dysfunction of CreA, a conserved transcription factor involved in carbon catabolite repression in many fungal species, causes abnormal asexual development (conidiation) under liquid-submerged culture conditions specifically in the presence of glucose. The loss of creA decreased GAG production independent of carbon sources. Furthermore, CreA contributed to asexual development and GAG production via distinct pathways. CreA promoted A. fumigatus GAG production by positively regulating GAG biosynthetic genes (uge3 and agd3). CreA suppressed asexual development in glucose liquid-submerged culture conditions via central conidiation genes (brlA, abaA, and wetA) and their upstream activators (flbC and flbD). Restoration of brlA expression to the wild-type level by flbC or flbD deletion abolished the abnormal submerged conidiation in the creA null mutant but did not restore GAG production. The C-terminal region of CreA was crucial for the suppression of asexual development, and the repressive domain contributed to GAG production. Overall, CreA is involved in GAG production and asexual development in an inverse manner.


Asunto(s)
Aspergillus fumigatus , Factores de Transcripción , Aspergillus fumigatus/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Esporas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Biopelículas , Glucosa
19.
BMC Plant Biol ; 24(1): 456, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38789931

RESUMEN

BACKGROUND: Baolia H.W.Kung & G.L.Chu is a monotypic genus only known in Diebu County, Gansu Province, China. Its systematic position is contradictory, and its morphoanatomical characters deviate from all other Chenopodiaceae. Recent study has regarded Baolia as a sister group to Corispermoideae. We therefore sequenced and compared the chloroplast genomes of this species, and resolved its phylogenetic position based on both chloroplast genomes and marker sequences. RESULTS: We sequenced 18 chloroplast genomes of 16 samples from two populations of Baolia bracteata and two Corispermum species. These genomes of Baolia ranged in size from 152,499 to 152,508 bp. Simple sequence repeats (SSRs) were primarily located in the LSC region of Baolia chloroplast genomes, and most of them consisted of single nucleotide A/T repeat sequences. Notably, there were differences in the types and numbers of SSRs between the two populations of B. bracteata. Our phylogenetic analysis, based on both complete chloroplast genomes from 33 species and a combination of three markers (ITS, rbcL, and matK) from 91 species, revealed that Baolia and Corispermoideae (Agriophyllum, Anthochlamys, and Corispermum) form a well-supported clade and sister to Acroglochin. According to our molecular dating results, a major divergence event between Acroglochin, Baolia, and Corispermeae occurred during the Middle Eocene, approximately 44.49 mya. Ancestral state reconstruction analysis showed that Baolia exhibited symplesiomorphies with those found in core Corispermoideae characteristics including pericarp and seed coat. CONCLUSIONS: Comparing the chloroplast genomes of B. bracteata with those of eleven typical Chenopodioideae and Corispermoideae species, we observed a high overall similarity and a one notable noteworthy case of inversion of approximately 3,100 bp. of DNA segments only in two Atriplex and four Chenopodium species. We suggest that Corispermoideae should be considered in a broader sense, it includes Corispermeae (core Corispermoideae: Agriophyllum, Anthochlamys, and Corispermum), as well as two new monotypic tribes, Acroglochineae (Acroglochin) and Baolieae (Baolia).


Asunto(s)
Amaranthaceae , Genoma del Cloroplasto , Filogenia , Amaranthaceae/genética , Amaranthaceae/anatomía & histología , Amaranthaceae/clasificación , Repeticiones de Microsatélite , China , ADN de Cloroplastos/genética , Análisis de Secuencia de ADN , Marcadores Genéticos
20.
Adv Funct Mater ; 34(19)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-39022395

RESUMEN

High-quality-factor microring resonators are highly desirable in many applications. Fabricating a microring resonator typically requires delicate instruments to ensure a smooth side wall of waveguides and 100-nm critical feature size in the coupling region. In this work, we demonstrate a new method "damascene soft nanoimprinting lithography" that can create high-fidelity waveguide by simply backfill an imprinted cladding template with a high refractive index polymer core. This method can easily realize high Q-factor polymer microring resonators (e.g., ~5 x 105 around 770 nm wavelength) without the use of any expensive instruments and can be conducted in a normal lab environment. The high Q-factors can be attributed to the residual layer-free feature and controllable meniscus cross-section profile of the filled polymer core. Furthermore, the new method is compatible with different polymers, yields low fabrication defects, enables new functionalities, and allows flexible substrate. These benefits can broaden the applicability of the fabricated microring resonator.

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