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1.
iScience ; 27(6): 110006, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38868202

RESUMO

Apolipoprotein E (apoE) plays a crucial role in the pathogenesis of Alzheimer's disease (AD). Microglia exhibit a substantial upregulation of apoE in AD-associated circumstances, despite astrocytes being the primary source of apoE expression and secretion in the brain. Although the role of astrocytic apoE in the brain has been extensively investigated, it remains unclear that whether and how apoE particles generated from astrocytes and microglia differ in biological characteristic and function. Here, we demonstrate the differences in size between apoE particles generated from microglia and astrocytes. Microglial apoE particles impair neurite growth and synapses, and promote neuronal senescence, whereas depletion of GPNMB (glycoprotein non-metastatic melanoma protein B) in microglial apoE particles mitigated these deleterious effects. In addition, human APOE4-expressing microglia are more neurotoxic than APOE3-bearing microglia. For the first time, these results offer concrete evidence that apoE particles produced by microglia are involved in neuronal senescence and toxicity.

2.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900038

RESUMO

A new cladosporol derivative xylophilum A (1), together with 10 known compounds (2-11), were isolated from the rice fermentation of the fungus Cladosporium xylophilum. Their structures were established by extensive spectroscopic methods and comparison of their NMR data with literatures. The antimicrobial activity of compound 1 against 11 kinds of pathogenic microbial was evaluated, but no significant activity was found (MIC >100 µg/ml).

3.
Sci Rep ; 14(1): 13898, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886449

RESUMO

A method has been developed to increase computational efficiency in Monte Carlo simulations of electron transport and interactions in matter. The method serves as the computational engine for the open-source code AMCSET (Aggie Monte Carlo Simulations of Electron and Ion Transport). The key is to combine n consecutive neighboring free flying distances into groups. Within each group, both flying distance and Mott scattering angles are obtained using Monte Carlo sampling under an equal energy approximation. This reduces the number of integrations of the tabulated differential Mott scattering cross-section in scattering angle selection, i.e., from 1000 to 1 if n = 1000. The method increases efficiency by more than 100 times. At the same time, the calculation still guarantees accuracy in calculating electron trajectory, excitation/ionization energy deposition, elastic scattering energy deposition, and displacement creation. For demonstration, 10 MeV electron bombardments of pure Fe with n up to 1000 are used as examples. The method, due to the availability of tabulated scattering cross-sections, is applicable for targets of the entire elemental table up to Z = 118, and for electron energies up to 900 MeV.

4.
Quant Imaging Med Surg ; 14(6): 3789-3802, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38846281

RESUMO

Background: The noninvasive prediction of sentinel lymph node (SLN) metastasis using quantitative magnetic resonance imaging (MRI), particularly with synthetic MRI (syMRI), is an emerging field. This study aimed to explore the potential added benefits of syMRI over conventional MRI and diffusion-weighted imaging (DWI) in predicting metastases in SLNs. Methods: This retrospective study consecutively enrolled 101 patients who were diagnosed with breast cancer (BC) and underwent SLN biopsy from December 2022 to October 2023 at the Affiliated Hospital of Jiangnan University. These patients underwent preoperative MRI including conventional MRI, DWI, and syMRI and were categorized into two groups according to the postoperative pathological results: those with and without metastatic SLNs. MRI morphological features, DWI, and syMRI-derived quantitative parameters of breast tumors were statistically compared between these two groups. Binary logistic regression was used to separately develop predictive models for determining the presence of SLN involvement, with variables that exhibited significant differences being incorporated. The performance of each model was evaluated through receiver operating characteristic (ROC) curve analysis, including the area under the curve (AUC), sensitivity, and specificity. Results: Compared to the group of 54 patients with BC but no metastatic SLNs, the group of 47 patients with BC and metastatic SLNs had a significantly larger maximum axis diameter [metastatic SLNs: median 2.40 cm, interquartile range (IQR) 1.50-3.00 cm; no metastatic SLNs: median 1.80 cm, IQR 1.37-2.50 cm; P=0.03], a higher proton density (PD) (78.44±11.92 vs. 69.20±10.63 pu; P<0.001), and a lower apparent diffusion coefficient (ADC) (metastatic SLNs: median 0.91×10-3 mm2/s, IQR 0.79-1.01 mm2/s; no metastatic SLNs: median 1.02×10-3 mm2/s, IQR 0.92-1.12 mm2/s; P=0.001). Moreover, the prediction model with maximum axis diameter and ADC yielded an AUC of 0.71 [95% confidence interval (CI): 0.618-0.802], with a sensitivity of 78.72% and a specificity of 51.85%; After addition of syMRI-derived PD to the prediction model, the AUC increased significantly to 0.86 (AUC: 0.86 vs. 0.71; 95% CI: 0.778-0.922; P=0.002), with a sensitivity of 80.85% and a specificity of 81.50%. Conclusions: Combined with conventional MRI and DWI, syMRI can offer additional value in enhancing the predictive performance of determining SLN status before surgery in patients with BC.

5.
Eur J Med Chem ; 275: 116610, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38896992

RESUMO

Mutations in IDH1 are commonly observed across various cancers, causing the conversion of α-KG to 2-HG. Elevated levels of 2-HG disrupt histone and DNA demethylation processes, promoting tumor development. Consequently, there is substantial interest in developing small molecule inhibitors targeting the mutant enzymes. Herein, we report a structure-based high-throughput virtual screening strategy using a natural products library, followed by hit-to-lead optimization. Through this process, we discover a potent compound, named 11s, which exhibited significant inhibition to IDH1 R132H and IDH1 R132C with IC50 values of 124.4 and 95.7 nM, respectively. Furthermore, 11s effectively reduced 2-HG formation, with EC50 values of 182 nM in U87 R132H cell, and 84 nM in HT-1080 cell. In addition, 11s significantly reduced U87 R132H and HT-1080 cell proliferation with GC50 values of 3.48 and 1.38 µM, respectively. PK-PD experiments further confirmed that compound 11s significantly decreased 2-HG formation in an HT-1080 xenograft mouse model, resulting in notable suppression of tumor growth without apparent loss in body weight.

6.
BMC Genomics ; 25(1): 525, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807041

RESUMO

BACKGROUND: The Rh blood group system is characterized by its complexity and polymorphism, encompassing 56 different antigens. Accurately predicting the presence of the C antigen using genotyping methods has been challenging. The objective of this study was to evaluate the accuracy of various genotyping methods for predicting the Rh C and to identify a suitable method for the Chinese Han population. METHODS: In total, 317 donors, consisting 223 D+ (including 20 with the Del phenotype) and 94 D- were randomly selected. For RHC genotyping, 48C and 109bp insertion were detected on the Real-time PCR platform and -292 substitution was analyzed via restriction fragment length polymorphism (RFLP). Moreover, the promoter region of the RHCE gene was sequenced to search for other nucleotide substitutions between RHC and RHc. Agreement between prediction methods was evaluated using the Kappa statistic, and comparisons between methods were conducted via the χ2 test. RESULTS: The analysis revealed that the 48C allele, 109bp insertion, a specific pattern observed in RFLP results, and wild-type alleles of seven single nucleotide polymorphisms (SNPs) were in strong agreement with the Rh C, with Kappa coefficients exceeding 0.8. However, there were instances of false positives or false negatives (0.6% false negative rate for 109bp insertion and 5.4-8.2% false positive rates for other methods). The 109bp insertion method exhibited the highest accuracy in predicting the Rh C, at 99.4%, compared to other methods (P values≤0.001). Although no statistical differences were found among other methods for predicting Rh C (P values>0.05), the accuracies in descending order were 48C (94.6%) > rs586178 (92.7%) > rs4649082, rs2375313, rs2281179, rs2072933, rs2072932, and RFLP (92.4%) > rs2072931 (91.8%). CONCLUSIONS: None of the methods examined can independently and accurately predict the Rh C. However, the 109bp insertion test demonstrated the highest accuracy for predicting the Rh C in the Chinese Han population. Utilizing the 109bp insertion test in combination with other methods may enhance the accuracy of Rh C prediction.


Assuntos
Povo Asiático , Técnicas de Genotipagem , Polimorfismo de Nucleotídeo Único , Sistema do Grupo Sanguíneo Rh-Hr , Humanos , Sistema do Grupo Sanguíneo Rh-Hr/genética , Povo Asiático/genética , Técnicas de Genotipagem/métodos , China , Genótipo , Alelos , Polimorfismo de Fragmento de Restrição , Frequência do Gene , Regiões Promotoras Genéticas , População do Leste Asiático
7.
Sci Total Environ ; 935: 173343, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777069

RESUMO

Niche convergence or conservatism have been proposed as essential mechanisms underlying elevational plant community assembly in tropical mountain ecosystems. Subtropical mountains, compared to tropical mountains, are likely to be shaped by a mixing of different geographic affinities of species and remain somehow unclear. Here, we used 31 0.1-ha permanent plots distributed in subtropical forests on the eastern and western aspects of the Gaoligong Mountains, southwest China between 1498 m and 3204 m a.sl. to evaluate how niche-based and biogeographic processes shape tree community assembly along elevational gradients. We analyzed the elevational patterns of taxonomic, phylogenetic and functional diversity, as well as of individual traits, and assessed the relative importance of environmental effects on these diversity measures. We then classified tree species as being either tropical affiliated or temperate affiliated and estimated their contribution to the composition of biogeographic affinities. Species richness decreased with elevation, and species composition showed apparent turnover across the aspects and elevations. Most traits exhibited convergent patterns across the entire elevational gradient. Phylogenetic and functional diversity showed opposing patterns, with phylogenetic diversity increasing and functional diversity decreasing with elevation. Soil nutrients, especially phosphorus and nitrogen, appeared to be the main abiotic variables driving the elevational diversity patterns. Communities at lower elevations were occupied by tropical genera, while highlands contained species of tropical and temperate biogeographic affinities. Moreover, the high phylogenetic diversity at high elevations were likely due to differences in evolutionary history between temperate and tropical species. Our results highlight the importance of niche convergence of tropical species and the legacy of biogeographic history on the composition and structure of subtropical mountain forests. Furthermore, limited soil phosphorus caused traits divergence and the partitioning for different forms of phosphorus may explain the high biodiversity found in phosphorus-limited subtropical forests.


Assuntos
Altitude , Biodiversidade , Florestas , Árvores , China , Filogenia , Ecossistema , Clima Tropical
8.
Front Endocrinol (Lausanne) ; 15: 1368944, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756997

RESUMO

Background: The 2022 World Health Organization (WHO) classification of pituitary neuroendocrine tumour (PitNET) supersedes the previous one in 2017 and further consolidates the role of transcription factors (TF) in the diagnosis of PitNET. Here, we investigated the clinical utility of the 2022 WHO classification, as compared to that of 2017, in a cohort of patients with non-functioning PitNET (NF-PitNET). Methods: A total of 113 NF-PitNET patients who underwent resection between 2010 and 2021, and had follow-up at Queen Mary Hospital, Hong Kong, were recruited. Surgical specimens were re-stained for the three TF: steroidogenic factor (SF-1), T-box family member TBX19 (TPIT) and POU class 1 homeobox 1 (Pit-1). The associations of different NF-PitNET subtypes with tumour-related outcomes were evaluated by logistic and Cox regression analyses. Results: Based on the 2022 WHO classification, the majority of NF-PitNET was SF-1-lineage tumours (58.4%), followed by TPIT-lineage tumours (18.6%), tumours with no distinct lineage (16.8%) and Pit-1-lineage tumours (6.2%). Despite fewer entities than the 2017 classification, significant differences in disease-free survival were present amongst these four subtypes (Log-rank test p=0.003), specifically between SF-1-lineage PitNET and PitNET without distinct lineage (Log-rank test p<0.001). In multivariable Cox regression analysis, the subtype of PitNET without distinct lineage (HR 3.02, 95% CI 1.28-7.16, p=0.012), together with tumour volume (HR 1.04, 95% CI 1.01-1.07, p=0.017), were independent predictors of a composite of residual or recurrent disease. Conclusion: The 2022 WHO classification of PitNET is a clinically useful TF and lineage-based system for subtyping NF-PitNET with different tumour behaviour and prognosis.


Assuntos
Tumores Neuroendócrinos , Neoplasias Hipofisárias , Organização Mundial da Saúde , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/classificação , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/metabolismo , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/classificação , Tumores Neuroendócrinos/metabolismo , Adulto , Idoso , Prognóstico , Adulto Jovem , Seguimentos , Proteínas com Domínio T/metabolismo
9.
J Med Chem ; 67(11): 9028-9053, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38787534

RESUMO

This work identified a class of cyanomethylquinolones (CQs) and their carboxyl analogues as potential multitargeting antibacterial candidates. Most of the prepared compounds showed high antibacterial activities against most of the tested bacteria, exhibiting lower MIC values (0.125-2 µg/mL) than those of clinical norfloxacin, ciprofloxacin, and clinafloxacin. The low hemolysis, drug resistance, and cytotoxicity, as well as good predictive pharmacokinetics of active CQs and carboxyl analogues revealed their development potential. Furthermore, they could eradicate the established biofilm, facilitating bacterial exposure to these antibacterial candidates. These active compounds could induce bacterial death through multitargeting effects, including intercalating into DNA, up-regulating reactive oxygen species, damaging membranes directly, and impeding metabolism. Moreover, the highly active cyclopropyl CQ 15 exhibited more effective in vivo anti-MRSA potency than ciprofloxacin. These findings highlight the potential of CQs and their carboxyl analogues as multitargeting broad-spectrum antibacterial candidates for treating intractable bacterial infections.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Quinolonas , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Animais , Quinolonas/farmacologia , Quinolonas/química , Quinolonas/síntese química , Humanos , Relação Estrutura-Atividade , Biofilmes/efeitos dos fármacos , Camundongos , Hemólise/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Ciprofloxacina/análogos & derivados , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
10.
Int J Mol Sci ; 25(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38791239

RESUMO

Bacillus velezensis FZB42 is a plant growth-promoting rhizobacterium (PGPR) and a model microorganism for biofilm studies. Biofilms are required for the colonization and promotion of plant growth in the rhizosphere. However, little is known about how the final stage of the biofilm life cycle is regulated, when cells regain their motility and escape the mature biofilm to spread and colonize new niches. In this study, the non-annotated gene ccdC was found to be involved in the process of biofilm dispersion. We found that the ccdC-deficient strain maintained a wrinkled state at the late stage of biofilm formation in the liquid-gas interface culture, and the bottom solution showed a clear state, indicating that no bacterial cells actively escaped, which was further evidenced by the formation of a cellular ring (biofilm pellicle) located on top of the preformed biofilm. It can be concluded that dispersal, a biofilm property that relies on motility proficiency, is also positively affected by the unannotated gene ccdC. Furthermore, we found that the level of cyclic diguanylate (c-di-GMP) in the ccdC-deficient strain was significantly greater than that in the wild-type strain, suggesting that B. velezensis exhibits a similar mechanism by regulating the level of c-di-GMP, the master regulator of biofilm formation, dispersal, and cell motility, which controls the fitness of biofilms in Pseudomonas aeruginosain. In this study, we investigated the mechanism regulating biofilm dispersion in PGPR.


Assuntos
Bacillus , Proteínas de Bactérias , Biofilmes , Biofilmes/crescimento & desenvolvimento , Bacillus/fisiologia , Bacillus/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , GMP Cíclico/metabolismo , GMP Cíclico/análogos & derivados , Regulação Bacteriana da Expressão Gênica , Rizosfera
13.
Front Public Health ; 12: 1252244, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450136

RESUMO

Introduction: The understanding of health-related information is essential for making informed decisions. However, providing health information in an understandable format for everyone is challenging due to differences in consumers' health status, disease knowledge, skills, and preferences. Tailoring health information to individual needs can improve comprehension and increase health literacy. Objective: The aim of our research was to analyze the extent to which consumers can customize consumer health information materials (CHIMs) for type-2 diabetes mellitus through various media types. Methods: We conducted a comprehensive search for various CHIMs across various media types, such as websites, apps, videos, and printed or printable forms. A representative sample of CHIMs was obtained for analysis through blocked randomization across the various media types. We conducted a quantitative content analysis to determine the frequency of user-centered customization options. Cross-comparisons were made to identify trends and variations in modifiable features among the media. Results: In our representative sample of 114 CHIMs, we identified a total of 24 modifiable features, which we grouped into five main categories: (i) language, (ii) text, (iii) audiovisual, (iv) presentation, and (v) medical content. Videos offered the most customization opportunities (95%), while 47% of websites and 26% of apps did not allow users to tailor health information. None of the printed or printable materials provided the option to customize the information. Overall, 65% of analyzed CHIMs did not allow users to tailor health information according to their needs. Conclusion: Our results show that CHIMs for type-2 diabetes mellitus could be significantly improved by providing more customization options for users. Further research is needed to investigate the effectiveness and usability of these options to enhance the development and appropriate provision of modifiable features in health information.


Assuntos
Informação de Saúde ao Consumidor , Diabetes Mellitus Tipo 2 , Letramento em Saúde , Humanos , Tomada de Decisões , Nível de Saúde
15.
Luminescence ; 39(4): e4729, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38548706

RESUMO

To further explore the relationship between aryl substituents and mechanofluorochromic (MFC) behaviors, four salicylaldimine-based difluoroboron complexes (ts-Ph BF2, ts-Ph-NA BF2, ts-2NA BF2, and ts-triphenylamine [TPA] BF2), including aromatic substituents with different steric hindrance effects, were designed and successfully synthesized. Four complexes with twisted molecular conformation displayed intramolecular charge transfer and aggregation-induced emission properties. Under external mechanical stimuli, the as-synthesized powders of ts-Ph BF2, ts-Ph-NA BF2, and ts-TPA BF2 exhibited redshift fluorescence emission behaviors, and ts-Ph BF2 and ts-TPA BF2 could be recovered to original shifts by fuming, but ts-Ph-NA BF2 displayed irreversible switching. ts-2NA BF2 had no change during the grinding and fuming processes. The results indicated that the MFC behaviors could be attributed to the phase transformation between the well-defined crystalline and disordered amorphous states by X-ray diffraction measurement. Further research illustrated that ts-TPA BF2 with the most significant MFC phenomenon could be applied in data security protection in ink-free rewritable paper.


Assuntos
Segurança Computacional , Difração de Raios X
16.
Neuron ; 112(10): 1676-1693.e12, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38513667

RESUMO

Neuronal loss is the central issue in Alzheimer's disease (AD), yet no treatment developed so far can halt AD-associated neurodegeneration. Here, we developed a monoclonal antibody (mAb2A7) against 217 site-phosphorylated human tau (p-tau217) and observed that p-tau217 levels positively correlated with brain atrophy and cognitive impairment in AD patients. Intranasal administration efficiently delivered mAb2A7 into male PS19 tauopathic mouse brain with target engagement and reduced tau pathology/aggregation with little effect on total soluble tau. Further, mAb2A7 treatment blocked apoptosis-associated neuronal loss and brain atrophy, reversed cognitive deficits, and improved motor function in male tauopathic mice. Proteomic analysis revealed that mAb2A7 treatment reversed alterations mainly in proteins associated with synaptic functions observed in murine tauopathy and AD brain. An antibody (13G4) targeting total tau also attenuated tau-associated pathology and neurodegeneration but impaired the motor function of male tauopathic mice. These results implicate p-tau217 as a potential therapeutic target for AD-associated neurodegeneration.


Assuntos
Doença de Alzheimer , Anticorpos Monoclonais , Tauopatias , Proteínas tau , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Camundongos , Doença de Alzheimer/patologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Doença de Alzheimer/tratamento farmacológico , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/administração & dosagem , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Imunoterapia/métodos , Camundongos Transgênicos , Degeneração Neural/patologia , Degeneração Neural/tratamento farmacológico , Fosforilação , Proteínas tau/metabolismo , Tauopatias/tratamento farmacológico
18.
Zhongguo Gu Shang ; 37(2): 135-41, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38425063

RESUMO

OBJECTIVE: To evaluate the feasibility and accuracy of virtual preoperative planning and 3D-printed templates for pre-contoured plates for the treatment of posterior wall fractures of the acetabulum. METHODS: A retrospective analysis of 29 patients with posterior acetabular wall fractures treated between August 2017 and March 2021 were divided into 2 groups based on whether to use preoperative virtual planning and 3D printed template. In 3D-printing group, there were 14 patients, including 10 males and 4 females; aged from 21 to 53 years old;CT-based virtual surgical planning was done using Mimics and 3-Matic software and 3D-printed templates for pre-contoured plates were adopted. In conventional group, there were 15 patients, including 10 males and 5 females;aged from 19 to 55 years old;conventional method of intra-operative contouring to adapt the plate to the fracture region was adopted. Blood loss, surgical time, radiographic quality of reduction, and hip function were compared between groups. RESULTS: The difference in operation time and intraoperative blood loss was significant(P<0.05). Twenty-three patients were followed up from 12 to 30 months, and the fractures in both groups healed with a healing time of 3 to 6 months. At the last follow-up, the Merle d'Aubign-Postel score of the 3D printed group was lower than that of the conventional group(P<0.05), with no significant differences in walking ability, hip mobility and total score(P>0.05). In 3D printing group, 6 cases were excellent, 5 cases were good, 3 cases were fair;in conventional group, 5 cases were excellent, 5 cases were good, 4 cases were fair, 1 case was worse;no significant difference between two groups(P>0.05). CONCLUSION: Virtual preoperative planning and 3D-printed templates for pre-contoured plates can reduce operative time and the blood loss of surgery, improve the quality of reduction. This method is efficient, accurate and reliable to treat acetabular posterior wall fractures.


Assuntos
Fraturas Ósseas , Fraturas do Quadril , Fraturas da Coluna Vertebral , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Fixação Interna de Fraturas/métodos , Estudos Retrospectivos , Fraturas do Quadril/cirurgia , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Acetábulo/lesões , Impressão Tridimensional , Placas Ósseas , Resultado do Tratamento
19.
Plant Biotechnol J ; 22(6): 1652-1668, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38345936

RESUMO

Rhizomes are modified stems that grow underground and produce new individuals genetically identical to the mother plant. Recently, a breakthrough has been made in efforts to convert annual grains into perennial ones by utilizing wild rhizomatous species as donors, yet the developmental biology of this organ is rarely studied. Oryza longistaminata, a wild rice species featuring strong rhizomes, provides a valuable model for exploration of rhizome development. Here, we first assembled a double-haplotype genome of O. longistaminata, which displays a 48-fold improvement in contiguity compared to the previously published assembly. Furthermore, spatiotemporal transcriptomics was performed to obtain the expression profiles of different tissues in O. longistaminata rhizomes and tillers. Two spatially reciprocal cell clusters, the vascular bundle 2 cluster and the parenchyma 2 cluster, were determined to be the primary distinctions between the rhizomes and tillers. We also captured meristem initiation cells in the sunken area of parenchyma located at the base of internodes, which is the starting point for rhizome initiation. Trajectory analysis further indicated that the rhizome is regenerated through de novo generation. Collectively, these analyses revealed a spatiotemporal transcriptional transition underlying the rhizome initiation, providing a valuable resource for future perennial crop breeding.


Assuntos
Oryza , Rizoma , Transcriptoma , Rizoma/genética , Rizoma/crescimento & desenvolvimento , Rizoma/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Transcriptoma/genética , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica , Genoma de Planta/genética
20.
bioRxiv ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38405892

RESUMO

Autophagic mechanisms that maintain nuclear envelope homeostasis are bulwarks to aging and disease. By leveraging 4D lattice light sheet microscopy and correlative light and electron tomography, we define a quantitative and ultrastructural timeline of a nuclear macroautophagy (nucleophagy) pathway in yeast. Nucleophagy initiates with a rapid local accumulation of the nuclear cargo adaptor Atg39 at the nuclear envelope adjacent to the nucleus-vacuole junction and is delivered to the vacuole in ~300 seconds through an autophagosome intermediate. Mechanistically, nucleophagy incorporates two consecutive and genetically defined membrane fission steps: inner nuclear membrane (INM) fission generates a lumenal vesicle in the perinuclear space followed by outer nuclear membrane (ONM) fission to liberate a double membraned vesicle to the cytosol. ONM fission occurs independently of phagophore engagement and instead relies surprisingly on dynamin-like protein1 (Dnm1), which is recruited to sites of Atg39 accumulation at the nuclear envelope. Loss of Dnm1 compromises nucleophagic flux by stalling nucleophagy after INM fission. Our findings reveal how nuclear and INM cargo are removed from an intact nucleus without compromising its integrity, achieved in part by a non-canonical role for Dnm1 in nuclear envelope remodeling.

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