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1.
Article in English | MEDLINE | ID: mdl-38824095

ABSTRACT

BACKGROUND: In patients with hilar cholangiocarcinoma (HCCA), radical resection can be achieved by resection and reconstruction of the vasculature. However, whether vascular reconstruction (VR) improves long-term and short-term prognosis has not been demonstrated comprehensively. METHODS: This was a retrospective multicenter study of patients who received surgery for HCCA with or without VR. Variables associated with overall survival (OS) and recurrence-free survival (RFS) were identified based on Cox regression. Kaplan-Meier curves were used to explore the impact of VR. Restricted mean survival time (RMST) was used for comparisons of short-term survival between the groups. Patients' intraoperative and postoperative characteristics were compared. RESULTS: Totally 447 patients were enrolled. We divided these patients into 3 groups: VR with radical resections (n = 84); non-VR radical resections (n = 309) and non-radical resection (we pooled VR-nonradical and non-VR nonradical together, n = 54). Cox regression revealed that carbohydrate antigen 242 (CA242), vascular invasion, lymph node metastasis and poor differentiation were independent risk factors for OS and RFS. There was no significant difference of RMST between the VR and non-VR radical groups within 12 months after surgery (10.18 vs. 10.76 mon, P = 0.179), although the 5-year OS (P < 0.001) and RFS (P < 0.001) were worse in the VR radical group. The incidences of most complications were not significantly different, but those of bile leakage (P < 0.001) and postoperative infection (P = 0.009) were higher in the VR radical group than in the non-VR radical group. Additionally, the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) up to 7 days after surgery tended to decrease in all groups. There was no significant difference in the incidence of postoperative liver failure between the VR and non-VR radical groups. CONCLUSIONS: Radical resection can be achieved with VR to improve the survival rate without worsening short-term survival compared with resection with non-VR. After adequate assessment of the patient's general condition, VR can be considered in the resection.

2.
BMC Ecol Evol ; 24(1): 74, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38831426

ABSTRACT

BACKGROUND: The geographic patterns of plant diversity in the Qinghai-Tibet Plateau (QTP) have been widely studied, but few studies have focused on wetland plants. This study quantified the geographic patterns of wetland plant diversity in the QTP through a comprehensive analysis of taxonomic, phylogenetic and functional indices. METHODS: Based on a large number of floras, monographs, specimens and field survey data, we constructed a comprehensive dataset of 1,958 wetland plant species in the QTP. Species richness (SR), phylogenetic diversity (PD), functional diversity (FD), net relatedness index (NRI) and net functional relatedness index (NFRI) were used to assess the taxonomic, phylogenetic and functional diversity of wetland plants. We explored the relationships between the diversity indices and four categories of environmental variables (i.e. energy-water, climate seasonality, topography and human activities). We used four diversity indices, namely endemic species richness, weighted endemism, phylogenetic endemism and functional endemism, together with the categorical analysis of neo- and paleo-endemism (CANAPE), to identify the endemic centers of wetland plants in the QTP. RESULTS: SR, PD and FD were highly consistent and showed a decreasing trend from southeast to northwest, decreasing with increasing elevation. The phylogenetic structure of wetland plant assemblages in most parts of the plateau is mainly clustered. The functional structure of wetland plant assemblages in the southeast of the plateau is overdispersed, while the functional structure of wetland plant assemblages in other areas is clustered. Energy-water and climate seasonality were the two most important categories of variables affecting wetland plant diversity. Environmental variables had a greater effect on the functional structure of wetland plants than on the phylogenetic structure. This study identified seven endemic centres, mainly in the Himalayas and Hengduan Mountains. CONCLUSIONS: Climate and topography are the main factors determining the geographic distribution of wetland plant diversity at large scales. The majority of grid cells in the QTP with significant phylogenetic endemism were mixed and super-endemism. At large scales, compared to climate and topography, human activities may not have a negative impact on wetland plant diversity in the QTP.


Subject(s)
Biodiversity , Plants , Wetlands , Plants/classification , Tibet , Phylogeny , China
3.
J Mol Cell Biol ; 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38830800

ABSTRACT

Zeste white 10 (ZW10) was first identified as a centromere/kinetochore protein encoded by the ZW10 gene in Drosophila. ZW10 guides the spindle assembly checkpoint signaling during mitotic chromosome segregation in metazoans. Recent studies have shown that ZW10 is also involved in membranous organelle interactions during interphase and plays a vital role in membrane transport between the endoplasmic reticulum and Golgi apparatus. Despite these findings, the precise molecular mechanisms by which ZW10 regulates interactions between membranous organelles in interphase and the assembly of membraneless organelle kinetochore in mitosis remain elusive. Here, we highlight how ZW10 forms context-dependent protein complexes during the cell cycle. These complexes are essential for mediating membrane trafficking in interphase and ensuring the accurate segregation of chromosomes in mitosis.

4.
Front Genet ; 15: 1242974, 2024.
Article in English | MEDLINE | ID: mdl-38699230

ABSTRACT

Background: Allergic rhinitis (AR) is a widespread allergic airway disease that results from a complex interplay between genetic and environmental factors and affects approximately 10%-40% of the global population. Pollen is a common allergen, and exposure to pollen can cause epigenetic changes. However, the mechanism underlying pollen-induced DNA methylation changes and their potential effects on the allergic march are still unclear. The purpose of this study was to explore the methylation-driven mechanisms of AR during the pollen and non-pollen seasons using bioinformatics analysis and to investigate their relationship with asthma. Methods: We downloaded DNA methylation and gene expression data from the GEO database (GSE50387: GSE50222, GSE50101) and identified differentially methylated positions (DMPs) and differentially expressed genes (DEGs) during the pollen and non-pollen seasons using the CHAMP and limma packages. Through correlation analysis, we identified methylation-driven genes and performed pathway enrichment analysis to annotate their functions. We incorporated external data on AR combined with asthma (GSE101720) for analysis to identify key CpGs that promote the transformation of AR to asthma. We also utilized external data on olive pollen allergy (GSE54522) for analysis to validate the methylation-driven genes. Weighted correlation network analysis (WGCNA) was employed to identify gene modules significantly correlated with pollen allergy. We extracted genes related to the key methylation-driven gene ZNF667-AS1 from the significant module and performed pathway intelligent clustering using KOBAS-i. We also utilized gene set enrichment analysis to explore the potential function of ZNF667-AS1. Results: We identified 20 and 24 CpG-Gene pairings during the pollen and non-pollen seasons. After incorporating external data from GSE101720, we found that ZNF667-AS1 is a key gene that may facilitate the transformation of AR into asthma during the pollen season. This finding was further validated in another external dataset, GSE54522, which is associated with pollen allergy. WGCNA identified 17 modules, among which the blue module showed significant correlation with allergies. ZNF667-AS1 was located in the blue module. We performed pathway analysis on the genes correlated with ZNF667-AS1 extracted from the blue module and identified a prominent cluster of pathways in the KOBAS-i results, including Toll-like receptor (TLR) family, MyD88, MAPK, and oxidative stress. Gene set enrichment analysis around cg05508084 (paired with ZNF667-AS1) also indicated its potential involvement in initiating and modulating allergic inflammation from the perspective of TLR and MAPK signaling. Conclusion: We identified methylation-driven genes and their related pathways during the pollen and non-pollen seasons in patients with AR and identified key CpGs that promote the transformation of AR into asthma due to pollen exposure. This study provides new insights into the underlying molecular mechanisms of the transformation of AR to asthma.

5.
Sci Adv ; 10(19): eadl4449, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38718124

ABSTRACT

Metal-organic frameworks (MOFs) hold great promise for diverse applications when combined with polymers. However, a persistent challenge lies in the susceptibility of exposed MOF pores to molecule and polymer penetration, compromising the porosity and overall performance. Here, we design a molecular-caged MOF (MC-MOF) to achieve contracted window without sacrificing the MOF porosity by torsional conjugated ligands. These molecular cages effectively shield against the undesired molecule penetration during polymerization, thereby preserving the pristine porosity of MC-MOF and providing outstanding light and thermal management to the composites. The polymer containing 0.5 wt % MC-MOF achieves an 83% transmittance and an exceptional haze of 93% at 550 nanometers, coupled with remarkable thermal insulation. These MC-MOF/polymer composites offer the potential for more uniform daylighting and reduced energy consumption in sustainable buildings when compared to traditional glass materials. This work delivers a general method to uphold MOF porosity in polymers through molecular cage design, advancing MOF-polymer applications in energy and sustainability.

6.
J Clin Anesth ; 96: 111493, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38723416

ABSTRACT

STUDY OBJECTIVE: The use of hydroxyethyl starch 130/0.4 has been linked to renal injury in critically ill patients, but its impact on surgical patients remains uncertain. DESIGN: A retrospective cohort study. SETTING: This study was conducted at one tertiary care hospital in China. PATIENTS: We evaluated the records of 51,926 Chinese adults who underwent noncardiac surgery from 2013 to 2022. Patients given a combination of hydroxyethyl starch 130/0.4 and crystalloids were propensity-matched at a 1: 1 ratio of baseline characteristics to patients given only crystalloids (11,725 pairs). INTERVENTIONS: Eligible patients were divided into those given a combination of hydroxyethyl starch 130/0.4 and crystalloid during surgery and a reference crystalloid group consisting of patients who were not given any colloid. MEASUREMENTS: The primary outcome was the incidence of acute kidney injury. Secondarily, acute kidney injury stage, need for renal replacement therapy, intensive care unit transfer rate, and duration of postoperative hospitalization were considered. MAIN RESULTS: After matching, hydroxyethyl starch use [8.5 (IQR: 7.5-10.0) mL/kg] did not increase the incidence of acute kidney injury compared with that in the crystalloid group [2.0 vs. 2.2%, OR: 0.90 (0.74-1.08), P = 0.25]. Nor did hydroxyethyl starch use worsen acute kidney injury stage [OR 0.90 (0.75-1.08), P = 0.26]. No significant differences between the fluid groups were observed in renal replacement therapy [OR 0.60 (0.41-0.90), P = 0.02)] or intensive care unit transfers [OR 1.02 (0.95-1.09), P = 0.53] after Bonferroni correction. Even in a subset of patients at high risk of renal injury, hydroxyethyl starch use was not associated with worse outcomes. CONCLUSIONS: Hydroxyethyl starch 130/0.4 use was not significantly associated with a greater incidence of postoperative acute kidney injury compared to receiving crystalloid solutions only.

7.
Updates Surg ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38728004

ABSTRACT

The aim was to assess conditional survival for colon mucinous adenocarcinoma (MAC) patients, and to construct nomograms to predict conditional survival probability. Survival analysis was done using conditional survival, which was defined as the probability of surviving additional y years for patients who have survived for x years. The mathematical definition was express as: CS (y|x) = S (x + y)/S (x). Cox regression analyses were used to identify prognostic factors. A nomogram is constructed to predict conditional disease-free survival (DFS) and overall survival (OS) probability according to years that already survive. A total of 179 colon MAC patients were included. The 5-year DFS was 67% after surgery, and the 5-year survival probability of patients, who already survived 1, 2, 3, and 4 years were 75%, 87%, 95%, and 98%, respectively. The 5-year OS was 73% after surgery and increased to 76%, 82%, 88%, and 92% at 1, 2, 3, and 4 years, respectively. Subgroup analyses demonstrated the superiority of conditional survival was more pronounced in advanced stages than in stage I. And pT stage, pN stage, and lymphovascular invasion were significantly associated with DFS and OS. Conditional survival nomograms were constructed to predict the 5-year conditional DFS and OS probability given survival for 1, 2, 3, 4 years after surgery. Conditional survival can provide dynamic survival probability according to years that already survive, especially for patients with advanced stages. Taking into account the years already survived accounted for, novel nomograms contributed to effectively predicting conditional survival.

8.
Endocrine ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38730070

ABSTRACT

INTRODUCTION: The differential diagnosis of parathyroid carcinoma (PC)/parathyroid adenoma (PA) in parathyroid tumors is critical for their management and prognosis. Circulating tumor cells (CTCs) identification in the peripheral blood of parathyroid tumors remains unknown. In this study, we proposed to investigate the differences of CTCs in PC/PA and the relationship with clinicopathologic features to assess its relevance to PC and value in identifying PC/PA. METHODS AND MATERIALS: Peripheral blood was collected from 27 patients with PC and 37 patients with PA treated in our hospital, and the number of chromosome 8 aberrant CTCs was detected by negative magnetic bead sorting fluorescence in situ hybridization (NE-FISH). The differences of CTCs in PC/PA peripheral blood were compared and their diagnostic efficacy was evaluated, and the correlation between CTCs and clinicopathological features of PC was further explored. RESULTS: CTCs differed significantly in PC/PA (p = 0.0008) and were up-regulated in PC, with good diagnostic efficacy. CTCs combined with alkaline phosphatase (ALP) assay improved the diagnostic efficacy in identifying PC/PA (AUC = 0.7838, p = 0.0001). The number of CTCs was correlated with tumor dimensions, but not significantly correlated with clinical markers such as calcium and PTH and pathological features such as vascular invasion, lymph node metastasis and distant metastasis. CONCLUSION: As a non-invasive liquid biopsy method, CTCs test combined with ALP test can be used as an important reference basis for timely and accurate identification and treatment of PC. It is of great significance to improve the current situation of PC diagnosis, treatment and prognosis.

9.
J Mol Cell Biol ; 2024 May 06.
Article in English | MEDLINE | ID: mdl-38710586

ABSTRACT

Chromothripsis, a type of complex chromosomal rearrangement originally known as chromoanagenesis, has been a subject of extensive investigation due to its potential role in various diseases, particularly cancer. Chromothripsis involves the rapid acquisition of tens to hundreds of structural rearrangements within a short period, leading to complex alterations in one or a few chromosomes. This phenomenon is triggered by chromosome missegregation during mitosis. Errors in accurate chromosome segregation lead to formation of aberrant structural entities such as micronuclei or chromatin bridges. The association between chromothripsis and cancer has attracted significant interest, with potential implications for tumorigenesis and disease prognosis. This review aims to explore the intricate mechanisms and consequences of chromothripsis, with a specific focus on its association with mitotic perturbations. Herein, we discuss a comprehensive analysis of crucial molecular entities and pathways, exploring the intricate roles of the CIP2A-TOPBP1 complex, micronuclei formation, chromatin bridge processing, DNA damage repair, and mitotic checkpoints. Moreover, the review will highlight recent advancements in identifying potential therapeutic targets and the underlying molecular mechanisms associated with chromothripsis, paving the way for future therapeutic interventions in various diseases.

10.
Br J Ophthalmol ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38749530

ABSTRACT

BACKGROUND/AIMS: To distinguish the clinical feature of nanophthalmos (NNO) caused by mutations in protease serine 56 (PRSS56), membrane-type frizzled-related protein (MFRP), myelin regulatory factor (MYRF) and transmembrane protein 98 (TMEM98) and to evaluate the association between angle-closure glaucoma (ACG) and NNO. METHODS: Variants in those four genes were identified through exome sequencing/whole genome sequencing data, and bioinformatic analysis was conducted to identify pathogenic/likely pathogenic (P/LP) variants. This observational study comprehensively summarised ophthalmological data of 67 patients with NNO from 63 families. Ocular parameters from 68 eyes without surgical treatment were subjected to further analysis. RESULTS: Totally, 67 patients from 63 families harboured 57 P/LP variants in the four genes, including 30 in PRSS56 (47.6%), 23 in MFRP (36.5%), 5 in TMEM98 (7.9%) and 5 in MYRF (7.9%). ACG was present in 79.1% of patients. An analysis of ocular parameters from 68 eyes revealed that shorter axial length (AL), lower vitreous-to-AL ratios and severe foveal hypoplasia were associated with variants in PRSS56 and MFRP. Uveal effusion was more common in patients with PRSS56 variants, while retinitis pigmentosa was frequently observed in patients with MFRP variants. Patients with MYRF variants exhibited the thinnest retinal nerve fibre layer thickness. Patients with TMEM98 variants had an earlier average onset age of glaucoma. CONCLUSION: Variants in PRSS56 and MFRP are the most common genetic cause of NNO. ACG is a severe complication frequently observed in these patients. Earlier onset of ACG is observed in patients with dominant NNO, while foveal hypoplasia is more common in patients with recessive disease. Recognising these features is helpful in clinical care and genetic counselling.

11.
Heliyon ; 10(9): e30275, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38756568

ABSTRACT

Organizational resilience is a key concept in the study of sustainable corporate growth and indicates an organization's capacity to recover from adversity. It plays a crucial role in responding to uncertain crises. In recent years, academic interest in organizational resilience has increasingly gained prominence. This research uses CiteSpace and VOSviewer to provide a thorough visual analysis of pertinent international literature based on 342 pieces of closely linked literature about organizational resilience. The findings suggest that organizational resilience research is currently experiencing a development phase. Within this field, there is a substantial number of scholars involved, with the most prolific among them including Aleksic Aleksandar, Prayag Girish, and Griffiths Andrew. The networks of collaboration among these authors, nevertheless, are very scattered. Co-citation network research reveals the academics with the biggest sway in the field. Organizational resilience, conservation of resources theory, crisis management, corporate social responsibility, and emergency management are identified as research hotspots within the keyword co-citation network. Furthermore, to determine which countries and regions are the most influential, this study has created a cooperative network among them. China, the United States, and England are the top three nations with articles published. Not only are the highly cited journals respected in the management sector, but they also showcase noteworthy research accomplishments within the field. The purpose of this study is to investigate potential avenues for future research and offer helpful sources for choosing research subjects and developing theoretical frameworks in this area. The analysis is highly valuable as a reference for research on organizational resilience in different settings in the future.

12.
Discov Nano ; 19(1): 88, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38753219

ABSTRACT

With the popularity of smart terminals, wearable electronic devices have shown great market prospects, especially high-sensitivity pressure sensors, which can monitor micro-stimuli and high-precision dynamic external stimuli, and will have an important impact on future functional development. Compressible flexible sensors have attracted wide attention due to their simple sensing mechanism and the advantages of light weight and convenience. Sensors with high sensitivity are very sensitive to pressure and can detect resistance/current changes under pressure, which has been widely studied. On this basis, this review focuses on analyzing the performance impact of device structure design strategies on high sensitivity pressure sensors. The design of structures can be divided into interface microstructures and three-dimensional framework structures. The preparation methods of various structures are introduced in detail, and the current research status and future development challenges are summarized.

13.
ISME Commun ; 4(1): ycae058, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38770058

ABSTRACT

Extracellular electron transfer (EET) of microorganisms is a major driver of the microbial growth and metabolism, including reactions involved in the cycling of C, N, and Fe in anaerobic environments such as soils and sediments. Understanding the mechanisms of EET, as well as knowing which organisms are EET-capable (or can become so) is fundamental to electromicrobiology and geomicrobiology. In general, Gram-positive bacteria very seldomly perform EET due to their thick non-conductive cell wall. Here, we report that a Gram-positive Clostridium intestinale (C.i) attained EET-capability for ethanol metabolism only after forming chimera with electroactive Geobacter sulfurreducens (G.s). Mechanism analyses demonstrated that the EET was possible after the cell fusion of the two species was achieved. Under these conditions, the ethanol metabolism pathway of C.i was integrated by the EET pathway of G.s, by which achieved the oxidation of ethanol for the subsequent reduction of extracellular electron acceptors in the coculture. Our study displays a new approach to perform EET for Gram-positive bacteria via recruiting the EET pathway of an electroactive bacterium, which suggests a previously unanticipated prevalence of EET in the microbial world. These findings also provide new perspectives to understand the energetic coupling between bacterial species and the ecology of interspecies mutualisms.

14.
ISA Trans ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38772803

ABSTRACT

This paper addresses robust fault detection observer design for a class of discrete-time Takagi-Sugeno nonlinear systems. A novel design method is presented based on finite-frequency H-/H∞ indices and peak-to-peak analysis. The finite-frequency H- and H∞ indices are utilized to characterize fault sensitivity and disturbance robustness, respectively. The peak-to-peak analysis is used to derive a dynamic threshold. An iterative algorithm is further developed to reduce conservatism. Theoretical proof shows that the performance of the proposed method is not worse than some existing works. Simulation results demonstrate the validity and viability of the proposed method.

15.
BMC Urol ; 24(1): 111, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778291

ABSTRACT

BACKGROUND: Patients with spinal cord injury have a relatively high risk for bladder cancer and often complicated with bladder cancer in advanced stages, and the degree of aggressiveness of malignancy is high. Most of the literature is based on disease clinical features while, our study reviews the clinical characteristics and molecular mechanisms of spinal cord injury patients with bladder cancer, so that it might help clinicians better recognize and manage these patients. METHOD: We searched PubMed, Web of Science and Embase, using retrieval type like ("Neurogenic Lower Urinary Tract Dysfunction" OR "Spinal cord injury" OR "Spinal Cord Trauma") AND ("bladder cancer" OR "bladder neoplasm" OR "bladder carcinoma" OR "Urinary Bladder Neoplasms" OR "Bladder Tumor"). In Web of Science, the retrieval type was searched as "Topic", and in PubMed and Embase, as "All Field". The methodological quality of eligible studies and their risk of bias were assessed using the Newcastle-Ottawa scale. This article is registered in PROSPERO with the CBD number: CRD42024508514. RESULT: In WOS, we searched 219 related papers, in PubMed, 122 and in Embase, 363. Thus, a total of 254 articles were included after passing the screening, within a time range between 1960 and 2023. A comprehensive analysis of the data showed that the mortality and incidence rates of bladder cancer in spinal cord injury patients were higher than that of the general population, and the most frequent pathological type was squamous cell carcinoma. In parallel to long-term urinary tract infection and indwelling catheterization, the role of molecules such as NO, MiR 1949 and Rb 1. was found to be crucial pathogenetically. CONCLUSION: This review highlights the risk of bladder cancer in SCI patients, comprehensively addressing the clinical characteristics and related molecular mechanisms. However, given that there are few studies on the molecular mechanisms of bladder cancer in spinal cord injury, further research is needed to expand the understanding of the disease.


Subject(s)
Spinal Cord Injuries , Urinary Bladder Neoplasms , Spinal Cord Injuries/complications , Humans , Urinary Bladder Neoplasms/complications
16.
Jpn J Nurs Sci ; : e12603, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38766689

ABSTRACT

AIM: To investigate the current status of chewing ability and analyze the risk factors among Chinese community-dwelling older adults. METHODS: In this cross-sectional study, color-changeable gum and a color difference meter were used to assess chewing ability in the population. The statistical analysis employed multivariate logistic regression models to identify and quantify the factors influencing chewing ability. RESULTS: A total of 373 community-dwelling adults aged 65 and older in Chengdu, in the west of China, were included in this study; 64 individuals (17.2%) exhibited signs of poor chewing ability. Female (odds ratio [OR]: 0.124, 95% CI: 0.057-0.268, p < .001), education level with college degree and above (OR: 0.114, 95% CI: 0.030-0.434, p = .001), number of teeth less than 20 (OR: 5.401, 95% CI: 2.509-11.626, p < .001), and decreased oral diadochokinesis (OR: 4.445, 95% CI: 1.775-11.132, p = .001) were significant factors in chewing ability in this study, after adjustment for potential variables. CONCLUSIONS: The prevalence of decreased chewing ability among Chinese community-dwelling older adults was 17.2% and decreased chewing ability was associated with men, lower education level, less than 20 teeth and decreased oral diadochokinesis.

17.
Cell Discov ; 10(1): 54, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38769343

ABSTRACT

A long-standing hypothesis proposes that certain RNA(s) must exhibit structural roles in microtubule assembly. Here, we identify a long noncoding RNA (TubAR) that is highly expressed in cerebellum and forms RNA-protein complex with TUBB4A and TUBA1A, two tubulins clinically linked to cerebellar and myelination defects. TubAR knockdown in mouse cerebellum causes loss of oligodendrocytes and Purkinje cells, demyelination, and decreased locomotor activity. Biochemically, we establish the roles of TubAR in promoting TUBB4A-TUBA1A heterodimer formation and microtubule assembly. Intriguingly, different from the hypomyelination-causing mutations, the non-hypomyelination-causing mutation TUBB4A-R2G confers gain-of-function for an RNA-independent interaction with TUBA1A. Experimental use of R2G/A mutations restores TUBB4A-TUBA1A heterodimer formation, and rescues the neuronal cell death phenotype caused by TubAR knockdown. Together, we uncover TubAR as the long-elusive structural RNA for microtubule assembly and demonstrate how TubAR mediates microtubule assembly specifically from αß-tubulin heterodimers, which is crucial for maintenance of cerebellar myelination and activity.

18.
Redox Biol ; 73: 103174, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38701646

ABSTRACT

Ribosomes mediate protein synthesis, which is one of the most energy-demanding activities within the cell, and mitochondria are one of the main sources generating energy. How mitochondrial morphology and functions are adjusted to cope with ribosomal defects, which can impair protein synthesis and affect cell viability, is poorly understood. Here, we used the fission yeast Schizosaccharomyces Pombe as a model organism to investigate the interplay between ribosome and mitochondria. We found that a ribosomal insult, caused by the absence of Rpl2702, activates a signaling pathway involving Sty1/MAPK and mTOR to modulate mitochondrial morphology and functions. Specifically, we demonstrated that Sty1/MAPK induces mitochondrial fragmentation in a mTOR-independent manner while both Sty1/MAPK and mTOR increases the levels of mitochondrial membrane potential and mitochondrial reactive oxygen species (mROS). Moreover, we demonstrated that Sty1/MAPK acts upstream of Tor1/TORC2 and Tor1/TORC2 and is required to activate Tor2/TORC1. The enhancements of mitochondrial membrane potential and mROS function to promote proliferation of cells bearing ribosomal defects. Hence, our study reveals a previously uncharacterized Sty1/MAPK-mTOR signaling axis that regulates mitochondrial morphology and functions in response to ribosomal insults and provides new insights into the molecular and physiological adaptations of cells to impaired protein synthesis.

19.
Angew Chem Int Ed Engl ; : e202404747, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38807563

ABSTRACT

Ethynylbenziodoxol(on)es (EB(X)xs) reagents have emerged as useful reagents for peptide/protein modification due to their versatile reactivity and high selectivity. Herein, we report the successful introduction of ethynylbenziodoxoles (EBxs) on different amino acid building blocks (Lys/Orn/Dap), and show their compatibility with both solid phase peptide synthesis (SPPS) and solution phase peptide synthesis (SPS). The selective incorporation of the EBx core into peptide sequences enable efficient macrocyclizations under mild conditions for the synthesis of topologically unique cyclic and bicyclic peptides.

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