Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 9.321
Filter
2.
Med Oncol ; 41(6): 137, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38705933

ABSTRACT

Metastasis poses a significant challenge in combating tumors. Even in papillary thyroid cancer (PTC), which typically exhibits a favorable prognosis, high recurrence rates are attributed to metastasis. Cytoplasmic linker protein 170 (CLIP170) functions as a classical microtubule plus-end tracking protein (+TIP) and has shown close association with cell migration. Nevertheless, the specific impact of CLIP170 on PTC cells remains to be elucidated. Our analysis of the GEO and TCGA databases unveiled an association between CLIP170 and the progression of PTC. To explore the impact of CLIP170 on PTC cells, we conducted various assays. We evaluated its effects through CCK-8, wound healing assay, and transwell assay after knocking down CLIP170. Additionally, the influence of CLIP170 on the cellular actin structure was examined via immunofluorescence; we further investigated the molecular expressions of epithelial-mesenchymal transition (EMT) and the transforming growth factor-ß (TGF-ß) signaling pathways through Western blotting and RT-qPCR. These findings were substantiated through an in vivo nude mouse model of lung metastasis. We observed a decreased expression of CLIP170 in PTC in contrast to normal thyroid tissue. Functionally, the knockdown of CLIP170 (CLIP170KD) notably enhanced the metastatic potential and EMT of PTC cells, both in vitro and in vivo. Mechanistically, CLIP170KD triggered the activation of the TGF-ß pathway, subsequently promoting tumor cell migration, invasion, and EMT. Remarkably, the TGF-ß inhibitor LY2157299 effectively countered TGF-ß activity and significantly reversed tumor metastasis and EMT induced by CLIP170 knockdown. In summary, these findings collectively propose CLIP170 as a promising therapeutic target to mitigate metastatic tendencies in PTC.


Subject(s)
Epithelial-Mesenchymal Transition , Microtubule-Associated Proteins , Neoplasm Proteins , Signal Transduction , Thyroid Cancer, Papillary , Thyroid Neoplasms , Transforming Growth Factor beta , Animals , Female , Humans , Male , Mice , Cell Line, Tumor , Cell Movement , Lung Neoplasms/pathology , Lung Neoplasms/metabolism , Lung Neoplasms/secondary , Lung Neoplasms/genetics , Mice, Nude , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Neoplasm Metastasis , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Thyroid Cancer, Papillary/pathology , Thyroid Cancer, Papillary/metabolism , Thyroid Cancer, Papillary/genetics , Thyroid Neoplasms/pathology , Thyroid Neoplasms/metabolism , Thyroid Neoplasms/genetics , Transforming Growth Factor beta/metabolism
3.
PeerJ ; 12: e17032, 2024.
Article in English | MEDLINE | ID: mdl-38770093

ABSTRACT

Purpose: This study seeks to identify potential clinical biomarkers for osteoarthritis (OA) using bioinformatics and investigate OA mechanisms through cellular assays. Methods: Differentially Expressed Genes (DEGs) from GSE52042 (four OA samples, four control samples) were screened and analyzed with protein-protein interaction (PPI) analysis. Overlapping genes in GSE52042 and GSE206848 (seven OA samples, and seven control samples) were identified and evaluated using Gene Set Enrichment Analysis (GSEA) and clinical diagnostic value analysis to determine the hub gene. Finally, whether and how the hub gene impacts LPS-induced OA progression was explored by in vitro experiments, including Western blotting (WB), co-immunoprecipitation (Co-IP), flow cytometry, etc. Result: Bioinformatics analysis of DEGs (142 up-regulated and 171 down-regulated) in GSE52042 identified two overlapping genes (U2AF2, TPX2) that exhibit significant clinical diagnostic value. These genes are up-regulated in OA samples from both GSE52042 and GSE206848 datasets. Notably, TPX2, which AUC = 0.873 was identified as the hub gene. In vitro experiments have demonstrated that silencing TPX2 can alleviate damage to chondrocytes induced by lipopolysaccharide (LPS). Furthermore, there is a protein interaction between TPX2 and MMP13 in OA. Excessive MMP13 can attenuate the effects of TPX2 knockdown on LPS-induced changes in OA protein expression, cell growth, and apoptosis. Conclusion: In conclusion, our findings shed light on the molecular mechanisms of OA and suggested TPX2 as a potential therapeutic target. TPX2 could promote the progression of LPS-induced OA by up-regulating the expression of MMP13, which provides some implications for clinical research.


Subject(s)
Cell Cycle Proteins , Chondrocytes , Disease Progression , Lipopolysaccharides , Matrix Metalloproteinase 13 , Microtubule-Associated Proteins , Osteoarthritis , Up-Regulation , Lipopolysaccharides/pharmacology , Osteoarthritis/genetics , Osteoarthritis/metabolism , Osteoarthritis/pathology , Osteoarthritis/chemically induced , Humans , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Matrix Metalloproteinase 13/metabolism , Matrix Metalloproteinase 13/genetics , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Chondrocytes/metabolism , Chondrocytes/pathology , Chondrocytes/drug effects , Computational Biology , Protein Interaction Maps
4.
J Exp Clin Cancer Res ; 43(1): 150, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38807192

ABSTRACT

BACKGROUND: Ovarian cancer has a high mortality rate mainly due to its resistance to currently used therapies. This resistance has been associated with the presence of cancer stem cells (CSCs), interactions with the microenvironment, and intratumoral heterogeneity. Therefore, the search for new therapeutic targets, particularly those targeting CSCs, is important for improving patient prognosis. HOOK1 has been found to be transcriptionally altered in a substantial percentage of ovarian tumors, but its role in tumor initiation and development is still not fully understood. METHODS: The downregulation of HOOK1 was performed in ovarian cancer cell lines using CRISPR/Cas9 technology, followed by growth in vitro and in vivo assays. Subsequently, migration (Boyden chamber), cell death (Western-Blot and flow cytometry) and stemness properties (clonal heterogeneity analysis, tumorspheres assay and flow cytometry) of the downregulated cell lines were analysed. To gain insights into the specific mechanisms of action of HOOK1 in ovarian cancer, a proteomic analysis was performed, followed by Western-blot and cytotoxicity assays to confirm the results found within the mass spectrometry. Immunofluorescence staining, Western-blotting and flow cytometry were also employed to finish uncovering the role of HOOK1 in ovarian cancer. RESULTS: In this study, we observed that reducing the levels of HOOK1 in ovarian cancer cells reduced in vitro growth and migration and prevented tumor formation in vivo. Furthermore, HOOK1 reduction led to a decrease in stem-like capabilities in these cells, which, however, did not seem related to the expression of genes traditionally associated with this phenotype. A proteome study, along with other analysis, showed that the downregulation of HOOK1 also induced an increase in endoplasmic reticulum stress levels in these cells. Finally, the decrease in stem-like properties observed in cells with downregulated HOOK1 could be explained by an increase in cell death in the CSC population within the culture due to endoplasmic reticulum stress by the unfolded protein response. CONCLUSION: HOOK1 contributes to maintaining the tumorigenic and stemness properties of ovarian cancer cells by preserving protein homeostasis and could be considered an alternative therapeutic target, especially in combination with inducers of endoplasmic reticulum or proteotoxic stress such as proteasome inhibitors.


Subject(s)
Autophagy , Endoplasmic Reticulum Stress , Neoplastic Stem Cells , Ovarian Neoplasms , Female , Humans , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/pathology , Ovarian Neoplasms/genetics , Mice , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Animals , Cell Line, Tumor , Proteostasis , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Cell Proliferation , Cell Movement
5.
Front Immunol ; 15: 1416914, 2024.
Article in English | MEDLINE | ID: mdl-38817605

ABSTRACT

Background: Angiogenesis, the process of forming new blood vessels from pre-existing ones, plays a crucial role in the development and advancement of cancer. Although blocking angiogenesis has shown success in treating different types of solid tumors, its relevance in prostate adenocarcinoma (PRAD) has not been thoroughly investigated. Method: This study utilized the WGCNA method to identify angiogenesis-related genes and assessed their diagnostic and prognostic value in patients with PRAD through cluster analysis. A diagnostic model was constructed using multiple machine learning techniques, while a prognostic model was developed employing the LASSO algorithm, underscoring the relevance of angiogenesis-related genes in PRAD. Further analysis identified MAP7D3 as the most significant prognostic gene among angiogenesis-related genes using multivariate Cox regression analysis and various machine learning algorithms. The study also investigated the correlation between MAP7D3 and immune infiltration as well as drug sensitivity in PRAD. Molecular docking analysis was conducted to assess the binding affinity of MAP7D3 to angiogenic drugs. Immunohistochemistry analysis of 60 PRAD tissue samples confirmed the expression and prognostic value of MAP7D3. Result: Overall, the study identified 10 key angiogenesis-related genes through WGCNA and demonstrated their potential prognostic and immune-related implications in PRAD patients. MAP7D3 is found to be closely associated with the prognosis of PRAD and its response to immunotherapy. Through molecular docking studies, it was revealed that MAP7D3 exhibits a high binding affinity to angiogenic drugs. Furthermore, experimental data confirmed the upregulation of MAP7D3 in PRAD, correlating with a poorer prognosis. Conclusion: Our study confirmed the important role of angiogenesis-related genes in PRAD and identified a new angiogenesis-related target MAP7D3.


Subject(s)
Adenocarcinoma , Immunotherapy , Machine Learning , Neovascularization, Pathologic , Prostatic Neoplasms , Humans , Male , Prostatic Neoplasms/genetics , Prostatic Neoplasms/immunology , Prostatic Neoplasms/therapy , Prognosis , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/immunology , Immunotherapy/methods , Adenocarcinoma/genetics , Adenocarcinoma/immunology , Adenocarcinoma/therapy , Biomarkers, Tumor/genetics , Gene Expression Regulation, Neoplastic , Microtubule-Associated Proteins/genetics , Molecular Docking Simulation , Gene Expression Profiling , Angiogenesis
6.
Neoplasia ; 53: 101003, 2024 07.
Article in English | MEDLINE | ID: mdl-38759377

ABSTRACT

Dynamic changes in the endoplasmic reticulum (ER) morphology are central to maintaining cellular homeostasis. Microtubules (MT) facilitate the continuous remodeling of the ER network into sheets and tubules by coordinating with many ER-shaping protein complexes, although how this process is controlled by extracellular signals remains unknown. Here we report that TAK1, a kinase responsive to various growth factors and cytokines including TGF-ß and TNF-α, triggers ER tubulation by activating αTAT1, an MT-acetylating enzyme that enhances ER-sliding. We show that this TAK1/αTAT1-dependent ER remodeling promotes cell survival by actively downregulating BOK, an ER membrane-associated proapoptotic effector. While BOK is normally protected from degradation when complexed with IP3R, it is rapidly degraded upon their dissociation during the ER sheets-to-tubules conversion. These findings demonstrate a distinct mechanism of ligand-induced ER remodeling and suggest that the TAK1/αTAT1 pathway may be a key target in ER stress and dysfunction.


Subject(s)
Endoplasmic Reticulum , MAP Kinase Kinase Kinases , Microtubules , Signal Transduction , Microtubules/metabolism , Endoplasmic Reticulum/metabolism , Humans , MAP Kinase Kinase Kinases/metabolism , MAP Kinase Kinase Kinases/genetics , Acetylation , Animals , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Acetyltransferases/metabolism , Acetyltransferases/genetics , Endoplasmic Reticulum Stress , Mice , Microtubule Proteins
7.
Curr Biol ; 34(11): 2279-2293.e6, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38776902

ABSTRACT

Faithful chromosome segregation requires that sister chromatids establish bi-oriented kinetochore-microtubule attachments. The spindle assembly checkpoint (SAC) prevents premature anaphase onset with incomplete attachments. However, how microtubule attachment and checkpoint signaling are coordinated remains unclear. The conserved kinase Mps1 initiates SAC signaling by localizing transiently to kinetochores in prometaphase and is released upon bi-orientation. Using biochemistry, structure predictions, and cellular assays, we shed light on this dynamic behavior in Saccharomyces cerevisiae. A conserved N-terminal segment of Mps1 binds the neck region of Ndc80:Nuf2, the main microtubule receptor of kinetochores. Mutational disruption of this interface, located at the backside of the paired CH domains and opposite the microtubule-binding site, prevents Mps1 localization, eliminates SAC signaling, and impairs growth. The same interface of Ndc80:Nuf2 binds the microtubule-associated Dam1 complex. We demonstrate that the error correction kinase Ipl1/Aurora B controls the competition between Dam1 and Mps1 for the same binding site. Thus, binding of the Dam1 complex to Ndc80:Nuf2 may release Mps1 from the kinetochore to promote anaphase onset.


Subject(s)
Cell Cycle Proteins , Kinetochores , Microtubules , Protein Serine-Threonine Kinases , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Kinetochores/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/genetics , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Microtubules/metabolism , Cell Cycle Proteins/metabolism , Cell Cycle Proteins/genetics , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Nuclear Proteins
8.
Curr Biol ; 34(11): 2308-2318.e6, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38776904

ABSTRACT

The Mps1 and Aurora B kinases regulate and monitor kinetochore attachment to spindle microtubules during cell division, ultimately ensuring accurate chromosome segregation. In yeast, the critical spindle attachment components are the Ndc80 and Dam1 complexes (Ndc80c and DASH/Dam1c, respectively). Ndc80c is a 600-Å-long heterotetramer that binds microtubules through a globular "head" at one end and centromere-proximal kinetochore components through a globular knob at the other end. Dam1c is a heterodecamer that forms a ring of 16-17 protomers around the shaft of the single kinetochore microtubule in point-centromere yeast. The ring coordinates the approximately eight Ndc80c rods per kinetochore. In published work, we showed that a site on the globular "head" of Ndc80c, including residues from both Ndc80 and Nuf2, binds a bipartite segment in the long C-terminal extension of Dam1. Results reported here show, both by in vitro binding experiments and by crystal structure determination, that the same site binds a conserved segment in the long N-terminal extension of Mps1. It also binds, less tightly, a conserved segment in the N-terminal extension of Ipl1 (yeast Aurora B). Together with results from experiments in yeast cells and from biochemical assays reported in two accompanying papers, the structures and graded affinities identify a communication hub for ensuring uniform bipolar attachment and for signaling anaphase onset.


Subject(s)
Kinetochores , Microtubules , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Kinetochores/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Microtubules/metabolism , Phosphorylation , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Cycle Proteins/genetics , Nuclear Proteins
9.
Oncoimmunology ; 13(1): 2360275, 2024.
Article in English | MEDLINE | ID: mdl-38812570
10.
Int J Mol Sci ; 25(9)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38732148

ABSTRACT

Mutations in the LMNA gene-encoding A-type lamins can cause Limb-Girdle muscular dystrophy Type 1B (LGMD1B). This disease presents with weakness and wasting of the proximal skeletal muscles and has a variable age of onset and disease severity. This variability has been attributed to genetic background differences among individuals; however, such variants have not been well characterized. To identify such variants, we investigated a multigeneration family in which affected individuals are diagnosed with LGMD1B. The primary genetic cause of LGMD1B in this family is a dominant mutation that activates a cryptic splice site, leading to a five-nucleotide deletion in the mature mRNA. This results in a frame shift and a premature stop in translation. Skeletal muscle biopsies from the family members showed dystrophic features of variable severity, with the muscle fibers of some family members possessing cores, regions of sarcomeric disruption, and a paucity of mitochondria, not commonly associated with LGMD1B. Using whole genome sequencing (WGS), we identified 21 DNA sequence variants that segregate with the family members possessing more profound dystrophic features and muscle cores. These include a relatively common variant in coiled-coil domain containing protein 78 (CCDC78). This variant was given priority because another mutation in CCDC78 causes autosomal dominant centronuclear myopathy-4, which causes cores in addition to centrally positioned nuclei. Therefore, we analyzed muscle biopsies from family members and discovered that those with both the LMNA mutation and the CCDC78 variant contain muscle cores that accumulated both CCDC78 and RyR1. Muscle cores containing mislocalized CCDC78 and RyR1 were absent in the less profoundly affected family members possessing only the LMNA mutation. Taken together, our findings suggest that a relatively common variant in CCDC78 can impart profound muscle pathology in combination with a LMNA mutation and accounts for variability in skeletal muscle disease phenotypes.


Subject(s)
Lamin Type A , Microtubule-Associated Proteins , Muscle Proteins , Muscle, Skeletal , Adult , Female , Humans , Male , Middle Aged , Lamin Type A/genetics , Muscle Proteins/genetics , Muscle, Skeletal/pathology , Muscle, Skeletal/metabolism , Muscular Dystrophies, Limb-Girdle/genetics , Muscular Dystrophies, Limb-Girdle/pathology , Mutation , Pedigree , Microtubule-Associated Proteins/genetics
11.
Int J Mol Sci ; 25(10)2024 May 09.
Article in English | MEDLINE | ID: mdl-38791174

ABSTRACT

The spindle and kinetochore-associated complex subunit 3 (SKA3) is a protein essential for proper chromosome segregation during mitosis and thus responsible for maintaining genome stability. Although its involvement in the pathogenesis of various cancer types has been reported, the potential clinicopathological significance of SKA3 in pancreatic ductal adenocarcinoma (PDAC) has not been fully elucidated. Therefore, this study aimed to assess clinicopathological associations and prognostic value of SKA3 in PDAC. For this purpose, in-house immunohistochemical analysis on tissue macroarrays (TMAs), as well as a bioinformatic examination using publicly available RNA-Seq dataset, were performed. It was demonstrated that SKA3 expression at both mRNA and protein levels was significantly elevated in PDAC compared to control tissues. Upregulated mRNA expression constituted an independent unfavorable prognostic factor for the overall survival of PDAC patients, whereas altered SKA3 protein levels were associated with significantly better clinical outcomes. The last observation was particularly clear in the early-stage tumors. These findings render SKA3 a promising prognostic biomarker for patients with pancreatic ductal adenocarcinoma. However, further studies are needed to confirm this conclusion.


Subject(s)
Biomarkers, Tumor , Carcinoma, Pancreatic Ductal , Gene Expression Regulation, Neoplastic , Pancreatic Neoplasms , Humans , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/mortality , Male , Prognosis , Female , Middle Aged , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/mortality , Aged , Adenocarcinoma/genetics , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Adenocarcinoma/mortality , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Cell Cycle Proteins
12.
Int J Mol Sci ; 25(10)2024 May 18.
Article in English | MEDLINE | ID: mdl-38791543

ABSTRACT

Doublecortin, encoded by the DCX gene, plays a crucial role in the neuronal migration process during brain development. Pathogenic variants of the DCX gene are the major causes of the "lissencephaly (LIS) spectrum", which comprehends a milder phenotype like Subcortical Band Heterotopia (SBH) in heterozygous female subjects. We performed targeted sequencing in three unrelated female cases with SBH. We identified three DCX-related variants: a novel missense (c.601A>G: p.Lys201Glu), a novel nonsense (c.210C>G: p.Tyr70*), and a previously identified nonsense (c.907C>T: p.Arg303*) variant. The novel c.601A>G: p.Lys201Glu variant shows a mother-daughter transmission pattern across four generations. The proband exhibits focal epilepsy and achieved seizure freedom with a combination of oxcarbazepine and levetiracetam. All other affected members have no history of epileptic seizures. Brain MRIs of the affected members shows predominant fronto-central SBH with mixed pachygyria on the overlying cortex. The two nonsense variants were identified in two unrelated probands with SBH, severe drug-resistant epilepsy and intellectual disability. These novel DCX variants further expand the genotypic-phenotypic correlations of lissencephaly spectrum disorders. Our documented phenotypic descriptions of three unrelated families provide valuable insights and stimulate further discussions on DCX-SBH cases.


Subject(s)
Classical Lissencephalies and Subcortical Band Heterotopias , Doublecortin Domain Proteins , Doublecortin Protein , Microtubule-Associated Proteins , Pedigree , Phenotype , Humans , Female , Microtubule-Associated Proteins/genetics , Classical Lissencephalies and Subcortical Band Heterotopias/genetics , Classical Lissencephalies and Subcortical Band Heterotopias/pathology , Neuropeptides/genetics , Codon, Nonsense/genetics , Adult , Mutation, Missense , Child , Magnetic Resonance Imaging , Child, Preschool , Adolescent
13.
J Cell Biol ; 223(8)2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38743010

ABSTRACT

Basal bodies (BBs) are conserved eukaryotic structures that organize cilia. They are comprised of nine, cylindrically arranged, triplet microtubules (TMTs) connected to each other by inter-TMT linkages which stabilize the structure. Poc1 is a conserved protein important for BB structural integrity in the face of ciliary forces transmitted to BBs. To understand how Poc1 confers BB stability, we identified the precise position of Poc1 in the Tetrahymena BB and the effect of Poc1 loss on BB structure. Poc1 binds at the TMT inner junctions, stabilizing TMTs directly. From this location, Poc1 also stabilizes inter-TMT linkages throughout the BB, including the cartwheel pinhead and the inner scaffold. The full localization of the inner scaffold protein Fam161A requires Poc1. As ciliary forces are increased, Fam161A is reduced, indicative of a force-dependent molecular remodeling of the inner scaffold. Thus, while not essential for BB assembly, Poc1 promotes BB interconnections that establish an architecture competent to resist ciliary forces.


Subject(s)
Basal Bodies , Cilia , Microtubules , Protozoan Proteins , Tetrahymena thermophila , Basal Bodies/metabolism , Cilia/metabolism , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Microtubules/metabolism , Protein Binding , Protozoan Proteins/metabolism , Protozoan Proteins/genetics , Tetrahymena thermophila/metabolism , Tetrahymena thermophila/genetics
14.
Yi Chuan ; 46(5): 398-407, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38763774

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a progressive, chronic, and irreversible interstitial lung disease with unknown cause. To explore the role and regulatory mechanism of leucine-rich repeat-containing protein 15 (LRRC15) in IPF, bleomycin (BLM)-induced pulmonary fibrosis in mouse and A549 cells were constructed, and the expression of LRRC15 were detected. Then, MTT, GFP-RFP-LC3 dual fluorescent labeling system and Western blotting were used to investigate the effects of LRRC15 on cell activity and autophagy after transfection of siLRRC15, respectively. The results indicated that the expression of LRRC15 was significantly increased after the BLM treatment in mouse lung tissue and A549 cells. The designed and synthesized siLRRC15 followed by transfection into A549 cells resulted in a dramatic reduction in LRRC15 expression and partially restored the cell damage induced by BLM. Moreover, the expression of LC3-II and P62 were up-regulated, the amount of autophagosome were increased by GFP-RFP-LC3 dual fluorescent labeling assay after BLM treatment. Meanwhile, this study also showed that the key autophagy proteins LC3-II, ATG5 and ATG7 were up-regulated, P62 was down-regulated and autophagic flux were enhanced after further treatment of A549 cells with siLRRC15. The above findings suggest that LRRC15 is an indicator of epithelial cell damage and may participate in the regulation of fibrosis through autophagy mechanism in IPF. This study provides necessary theoretical basis for further elucidating the mechanism of IPF.


Subject(s)
Autophagy , Bleomycin , Animals , Humans , Male , Mice , A549 Cells , Autophagy/drug effects , Bleomycin/pharmacology , Idiopathic Pulmonary Fibrosis/metabolism , Idiopathic Pulmonary Fibrosis/pathology , Idiopathic Pulmonary Fibrosis/chemically induced , Idiopathic Pulmonary Fibrosis/genetics , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism
15.
Nat Commun ; 15(1): 3779, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38710684

ABSTRACT

The α-Aurora kinase is a crucial regulator of spindle microtubule organization during mitosis in plants. Here, we report a post-mitotic role for α-Aurora in reorganizing the phragmoplast microtubule array. In Arabidopsis thaliana, α-Aurora relocated from spindle poles to the phragmoplast midzone, where it interacted with the microtubule cross-linker MAP65-3. In a hypomorphic α-Aurora mutant, MAP65-3 was detected on spindle microtubules, followed by a diffuse association pattern across the phragmoplast midzone. Simultaneously, phragmoplast microtubules remained belatedly in a solid disk array before transitioning to a ring shape. Microtubules at the leading edge of the matured phragmoplast were often disengaged, accompanied by conspicuous retentions of MAP65-3 at the phragmoplast interior edge. Specifically, α-Aurora phosphorylated two residues towards the C-terminus of MAP65-3. Mutation of these residues to alanines resulted in an increased association of MAP65-3 with microtubules within the phragmoplast. Consequently, the expansion of the phragmoplast was notably slower compared to wild-type cells or cells expressing a phospho-mimetic variant of MAP65-3. Moreover, mimicking phosphorylation reinstated disrupted MAP65-3 behaviors in plants with compromised α-Aurora function. Overall, our findings reveal a mechanism in which α-Aurora facilitates cytokinesis progression through phosphorylation-dependent restriction of MAP65-3 associating with microtubules at the phragmoplast midzone.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Cytokinesis , Microtubule-Associated Proteins , Microtubules , Arabidopsis/metabolism , Arabidopsis/genetics , Microtubules/metabolism , Arabidopsis Proteins/metabolism , Arabidopsis Proteins/genetics , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Phosphorylation , Mutation , Spindle Apparatus/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Plants, Genetically Modified , Mitosis
16.
Elife ; 122024 May 17.
Article in English | MEDLINE | ID: mdl-38757694

ABSTRACT

The fragile X syndrome (FXS) represents the most prevalent form of inherited intellectual disability and is the first monogenic cause of autism spectrum disorder. FXS results from the absence of the RNA-binding protein FMRP (fragile X messenger ribonucleoprotein). Neuronal migration is an essential step of brain development allowing displacement of neurons from their germinal niches to their final integration site. The precise role of FMRP in neuronal migration remains largely unexplored. Using live imaging of postnatal rostral migratory stream (RMS) neurons in Fmr1-null mice, we observed that the absence of FMRP leads to delayed neuronal migration and altered trajectory, associated with defects of centrosomal movement. RNA-interference-induced knockdown of Fmr1 shows that these migratory defects are cell-autonomous. Notably, the primary Fmrp mRNA target implicated in these migratory defects is microtubule-associated protein 1B (MAP1B). Knocking down MAP1B expression effectively rescued most of the observed migratory defects. Finally, we elucidate the molecular mechanisms at play by demonstrating that the absence of FMRP induces defects in the cage of microtubules surrounding the nucleus of migrating neurons, which is rescued by MAP1B knockdown. Our findings reveal a novel neurodevelopmental role for FMRP in collaboration with MAP1B, jointly orchestrating neuronal migration by influencing the microtubular cytoskeleton.


Subject(s)
Cell Movement , Fragile X Mental Retardation Protein , Mice, Knockout , Microtubule-Associated Proteins , Neurons , Fragile X Mental Retardation Protein/metabolism , Fragile X Mental Retardation Protein/genetics , Animals , Neurons/metabolism , Neurons/physiology , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Mice , Fragile X Syndrome/metabolism , Fragile X Syndrome/genetics , Gene Knockdown Techniques
17.
Int J Mol Sci ; 25(9)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38732079

ABSTRACT

Long-term spaceflight is known to induce disruptions in circadian rhythms, which are driven by a central pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus, but the underlying molecular mechanisms remain unclear. Here, we developed a rat model that simulated microgravity and isolation environments through tail suspension and isolation (TSI). We found that the TSI environment imposed circadian disruptions to the core body temperature, heart rate, and locomotor-activity rhythms of rats, especially in the amplitude of these rhythms. In TSI model rats' SCNs, the core circadian gene NR1D1 showed higher protein but not mRNA levels along with decreased BMAL1 levels, which indicated that NR1D1 could be regulated through post-translational regulation. The autophagosome marker LC3 could directly bind to NR1D1 via the LC3-interacting region (LIR) motifs and induce the degradation of NR1D1 in a mitophagy-dependent manner. Defects in mitophagy led to the reversal of NR1D1 degradation, thereby suppressing the expression of BMAL1. Mitophagy deficiency and subsequent mitochondrial dysfunction were observed in the SCN of TSI models. Urolithin A (UA), a mitophagy activator, demonstrated an ability to enhance the amplitude of core body temperature, heart rate, and locomotor-activity rhythms by prompting mitophagy induction to degrade NR1D1. Cumulatively, our results demonstrate that mitophagy exerts circadian control by regulating NR1D1 degradation, revealing mitophagy as a potential target for long-term spaceflight as well as diseases with SCN circadian disruption.


Subject(s)
ARNTL Transcription Factors , Circadian Rhythm , Mitophagy , Nuclear Receptor Subfamily 1, Group D, Member 1 , Animals , Rats , Circadian Rhythm/physiology , Male , ARNTL Transcription Factors/metabolism , ARNTL Transcription Factors/genetics , Nuclear Receptor Subfamily 1, Group D, Member 1/metabolism , Nuclear Receptor Subfamily 1, Group D, Member 1/genetics , Weightlessness Simulation , Suprachiasmatic Nucleus/metabolism , Suprachiasmatic Nucleus/physiology , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Body Temperature , Heart Rate , Rats, Sprague-Dawley , Proteolysis
18.
Adv Exp Med Biol ; 1452: 21-35, 2024.
Article in English | MEDLINE | ID: mdl-38805123

ABSTRACT

Tubulin plays a fundamental role in cellular function and as the subject for microtubule-active agents in the treatment of ovarian cancer. Microtubule-binding proteins (e.g., tau, MAP1/2/4, EB1, CLIP, TOG, survivin, stathmin) and posttranslational modifications (e.g., tyrosination, deglutamylation, acetylation, glycation, phosphorylation, polyamination) further diversify tubulin functionality and may permit additional opportunities to understand microtubule behavior in disease and to develop microtubule-modifying approaches to combat ovarian cancer. Tubulin-based structures that project from suspended ovarian cancer cells known as microtentacles may contribute to metastatic potential of ovarian cancer cells and could represent an exciting novel therapeutic target.


Subject(s)
Microtubules , Neoplasm Metastasis , Ovarian Neoplasms , Protein Processing, Post-Translational , Tubulin , Humans , Tubulin/metabolism , Tubulin/chemistry , Female , Microtubules/metabolism , Ovarian Neoplasms/pathology , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/drug therapy , Animals , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Neoplasms/metabolism , Neoplasms/pathology , Neoplasms/drug therapy
19.
Nat Commun ; 15(1): 4467, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38796459

ABSTRACT

As daughter centrioles assemble during G2, they recruit conserved Ana3/RTTN followed by its partner Rcd4/PPP1R35. Together, this contributes to the subsequent recruitment of Ana1/CEP295, required for the centriole's conversion to a centrosome. Here, we show that Rcd4/PPP1R35 is also required to maintain 9-fold centriole symmetry in the Drosophila male germline; its absence causes microtubule triplets to disperse into a reduced number of doublet or singlet microtubules. rcd4-null mutant spermatocytes display skinny centrioles that elongate normally and localize centriolar components correctly. Mutant spermatocytes also have centrioles of normal girth that splay at their proximal ends when induced to elongate by Ana1 overexpression. Skinny and splayed spermatid centrioles can still recruit a proximal centriole-like (PCL) structure marking a capability to initiate features of centriole duplication in developing sperm. Thus, stable 9-fold symmetry of microtubule triplets is not essential for centriole growth, correct longitudinal association of centriole components, and aspects of centriole duplication.


Subject(s)
Centrioles , Drosophila Proteins , Microtubules , Spermatocytes , Centrioles/metabolism , Centrioles/ultrastructure , Centrioles/genetics , Animals , Male , Drosophila Proteins/metabolism , Drosophila Proteins/genetics , Spermatocytes/metabolism , Microtubules/metabolism , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Spermatids/metabolism , Spermatids/cytology , Cell Cycle Proteins/metabolism , Cell Cycle Proteins/genetics , Microtubule-Associated Proteins/metabolism , Microtubule-Associated Proteins/genetics , Mutation , Drosophila
20.
J Med Virol ; 96(6): e29690, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38804180

ABSTRACT

Autophagy is a degradational pathway with pivotal roles in cellular homeostasis and survival, including protection of neurons in the central nervous system (CNS). The significance of autophagy as antiviral defense mechanism is recognized and some viruses hijack and modulate this process to their advantage in certain cell types. Here, we present data demonstrating that the human neurotropic herpesvirus varicella zoster virus (VZV) induces autophagy in human SH-SY5Y neuronal cells, in which the pathway exerts antiviral activity. Productively VZV-infected SH-SY5Y cells showed increased LC3-I-LC3-II conversion as well as co-localization of the viral glycoprotein E and the autophagy receptor p62. The activation of autophagy was dependent on a functional viral genome. Interestingly, inducers of autophagy reduced viral transcription, whereas inhibition of autophagy increased viral transcript expression. Finally, the genotype of patients with severe ocular and brain VZV infection were analyzed to identify potential autophagy-associated inborn errors of immunity. Two patients expressing genetic variants in the autophagy genes ULK1 and MAP1LC3B2, respectively, were identified. Notably, cells of both patients showed reduced autophagy, alongside enhanced viral replication and death of VZV-infected cells. In conclusion, these results demonstrate a neuro-protective role for autophagy in the context of VZV infection and suggest that failure to mount an autophagy response is a potential predisposing factor for development of severe VZV disease.


Subject(s)
Autophagy , Herpesvirus 3, Human , Neurons , Humans , Herpesvirus 3, Human/physiology , Herpesvirus 3, Human/pathogenicity , Neurons/virology , Autophagy-Related Protein-1 Homolog/metabolism , Autophagy-Related Protein-1 Homolog/genetics , Virus Replication , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Varicella Zoster Virus Infection/virology , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism , Cell Line , Intracellular Signaling Peptides and Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Host-Pathogen Interactions
SELECTION OF CITATIONS
SEARCH DETAIL
...