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2.
Front Mol Biosci ; 11: 1398603, 2024.
Article in English | MEDLINE | ID: mdl-38863966

ABSTRACT

Polygonatum sibiricum (P. sibiricum), recognized as a precious nourishing Chinese traditional medicine, exhibits the pharmacological effect of anti-aging. In this work, we proposed a novel mechanism underlying this effect related to the less studied bioactive compounds fructooligosaccharides in P. sibiricum (PFOS) to identify the inhibition effect of the small glycosyl molecules on the age-related zinc metalloprotease carbonic anhydrase II (CA II). Molecular docking and molecular dynamics simulation were used to investigate the structural and energetic properties of the complex systems consisting of the CA II enzyme and two possible structures of PFOS molecules (PFOS-A and PFOS-B). The binding affinity of PFOS-A (-7.27 ± 1.02 kcal/mol) and PFOS-B (-8.09 ± 1.75 kcal/mol) shows the spontaneity of the binding process and the stability of the combination in the solvent. Based on the residue energy decomposition and nonbonded interactions analysis, the C-, D- and G-sheet fragments of the CA II were found to be crucial in binding process. Van der Waals interactions form on the hydrophobic surface of CAII mainly with 131PHE and 135VAL, while hydrogen bonds form on the hydrophilic surface mainly with 67ASN and 92GLN. The binding of PFOS results in the blocking of the zinc ions pocket and then inhibiting its catalytic activity, the stability of which has been further demonstrated by free energy landscape. These findings provide evidence of the effective inhibition of PFOS to CA II enzyme, which leads to a novel direction for exploring the mechanism of traditional Chinese medicine focused on small molecule fructooligosaccharides.

3.
Plant Sci ; 346: 112151, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38848768

ABSTRACT

Endosperm, the major storage organ in cereal grains, determines the grain yield and quality. Mitochondria provide the energy for dry matter accumulation, in the endosperm development. Although mitochondrial single-stranded DNA-binding proteins (mtSSBs) play a canonical role in the maintenance of single-stranded mitochondrial DNA, their molecular functions in RNA processing and endosperm development remain obscure. Here, we report a defective rice endosperm mutant, floury endosperm26 (flo26), which develops abnormal starch grains in the endosperm. Map-based cloning and complementation experiments showed that FLO26 allele encodes a mitochondrial single-stranded DNA-binding protein, named as mtSSB1.1. Loss of function of mtSSB1.1 affects the transcriptional level of many mitochondrially-encoded genes and RNA splicing of nad1, a core component of respiratory chain complex I in mitochondria. As a result, dysfunctional mature nad1 led to dramatically decreased complex I activity, thereby reducing ATP production. Our results reveal that mtSSB1.1 plays an important role in the maintenance of mitochondrial function and endosperm development by stabilizing the splicing of mitochondrial RNA in rice.

4.
Pathology ; 56(5): 671-680, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38852040

ABSTRACT

Flow cytometry can be applied in the detection of fluorescence in situ hybridisation (FISH) signals to efficiently analyse chromosomal aberrations. However, such interphase chromosome (IC) Flow-FISH protocols are currently limited to detecting a single colour. Furthermore, combining IC Flow-FISH with conventional multicolour flow cytometry is difficult because the DNA-denaturation step in FISH assay also disrupts cellular integrity and protein structures, precluding subsequent antigen-antibody binding and hindering concurrent labeling of surface antigens and FISH signals. We developed a working protocol for concurrent multicolour flow cytometry detection of nuclear IC FISH signals and cell surface markers. The protocol was validated by assaying sex chromosome content of blood cells, which was indicative of chimerism status in patients who had received sex-mismatched allogeneic haematopoietic stem cell transplants (allo-HSCT). The method was also adapted to detect trisomy 12 in chronic lymphocytic leukaemia (CLL) subjects. We first demonstrated the feasibility of this protocol in detecting multiple colours and concurrent nuclear and surface signals with high agreement. In clinical validation experiments, chimerism status was identified in clinical samples (n=56) using the optimised IC Flow-FISH method; the results tightly corresponded to those of conventional slide-based FISH (R2=0.9649 for XX cells and 0.9786 for XY cells). In samples from patients who received sex-mismatched allo-HSCT, individual chimeric statuses in different lineages could be clearly distinguished with high flexibility in gating strategies. Furthermore, in CLL samples with trisomy 12, this method could demonstrate that enriched trisomy 12 FISH signal was present in B cells rather than in T cells. Finally, by performing combined labelling of chromosome 12, X chromosome, and surface markers, we could detect rare residual recipient CLL cells with trisomy 12 after allo-HSCT. This adaptable protocol for multicolour and lineage-specific IC Flow-FISH advances the technique to allow for its potential application in various clinical contexts where conventional FISH assays are currently being utilised.


Subject(s)
Flow Cytometry , In Situ Hybridization, Fluorescence , Interphase , Leukemia, Lymphocytic, Chronic, B-Cell , Humans , In Situ Hybridization, Fluorescence/methods , Flow Cytometry/methods , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Female , Male , Hematopoietic Stem Cell Transplantation , Trisomy/diagnosis , Trisomy/genetics , Middle Aged , Chromosomes, Human, Pair 12/genetics
5.
Eur Radiol ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38724768

ABSTRACT

OBJECTIVES: Developing a deep learning radiomics model from longitudinal breast ultrasound and sonographer's axillary ultrasound diagnosis for predicting axillary lymph node (ALN) response to neoadjuvant chemotherapy (NAC) in breast cancer. METHODS: Breast cancer patients undergoing NAC followed by surgery were recruited from three centers between November 2016 and December 2022. We collected ultrasound images for extracting tumor-derived radiomics and deep learning features, selecting quantitative features through various methods. Two machine learning models based on random forest were developed using pre-NAC and post-NAC features. A support vector machine integrated these data into a fusion model, evaluated via the area under the curve (AUC), decision curve analysis, and calibration curves. We compared the fusion model's performance against sonographer's diagnosis from pre-NAC and post-NAC axillary ultrasonography, referencing histological outcomes from sentinel lymph node biopsy or axillary lymph node dissection. RESULTS: In the validation cohort, the fusion model outperformed both pre-NAC (AUC: 0.899 vs. 0.786, p < 0.001) and post-NAC models (AUC: 0.899 vs. 0.853, p = 0.014), as well as the sonographer's diagnosis of ALN status on pre-NAC and post-NAC axillary ultrasonography (AUC: 0.899 vs. 0.719, p < 0.001). Decision curve analysis revealed patient benefits from the fusion model across threshold probabilities from 0.02 to 0.98. The model also enhanced sonographer's diagnostic ability, increasing accuracy from 71.9% to 79.2%. CONCLUSION: The deep learning radiomics model accurately predicted the ALN response to NAC in breast cancer. Furthermore, the model will assist sonographers to improve their diagnostic ability on ALN status before surgery. CLINICAL RELEVANCE STATEMENT: Our AI model based on pre- and post-neoadjuvant chemotherapy ultrasound can accurately predict axillary lymph node metastasis and assist sonographer's axillary diagnosis. KEY POINTS: Axillary lymph node metastasis status affects the choice of surgical treatment, and currently relies on subjective ultrasound. Our AI model outperformed sonographer's visual diagnosis on axillary ultrasound. Our deep learning radiomics model can improve sonographers' diagnosis and might assist in surgical decision-making.

6.
Front Microbiol ; 15: 1329976, 2024.
Article in English | MEDLINE | ID: mdl-38803377

ABSTRACT

Hemorrhoids are a common ailment that can cause significant disruptions to one's daily life. While some researchers have speculated about a potential link between hemorrhoid development and gut microbes, there is currently insufficient evidence to support this claim. In this study, we collected samples from 60 hemorrhoid patients and analyzed the composition and characteristics of microbiomes in hemorrhoids. PCoA results revealed distinct differences between the microbiomes of hemorrhoids, skin-originated microbiomes, and gut microbes, highlighting the complex nature of hemorrhoidal microbiomes. The distribution characteristics of Staphylococcus suggest that the skin microbiome influences the microbiome of hemorrhoids. Additionally, we observed higher levels of Prevotella in two cases of thrombosed hemorrhoids compared to non-thrombosed hemorrhoids. This finding suggests that Prevotella may play a crucial role in the development of thrombosed hemorrhoids.

7.
Heliyon ; 10(10): e31238, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38803905

ABSTRACT

Purpose: The overall diagnostic value of fine-needle aspiration (FNA) is not as excellent as that of core needle biopsy (CNB). Limited research has investigated small cervical lymph nodes inaccessible to ultrasound-guided CNB due to technical challenges associated with their small size. Therefore, this study aimed to evaluate the accuracy of ultrasound-guided FNA in determining the etiology of small cervical lymph nodes. Methods: A retrospective analysis was conducted on patients who underwent FNA between May 2018 and May 2021 at our hospital. Cytological, histopathological, and clinical follow-up data were analyzed. The diagnostic yield of FNA was assessed based on sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy calculations. Results: This study included 505 patients, each with a small cervical lymph node under evaluation (total number of lymph nodes: 505). The average maximal diameter of the lymph nodes was 14.6 ± 6.2 mm. According to the Sydney system, the cytology results were as follows: Category I in 26 lymph nodes (5.1 %); Category II in 269 (53.3 %); Category III in 35 (6.9 %); Category IV in 17 (3.4 %); and Category V in 158 (31.3 %). We identified 212 malignant cases (203 metastases and 9 lymphomas) and 293 benign lymph nodes. FNA achieved high sensitivity (88.8 %), specificity (99.6 %), PPV (99.4 %), NPV (91.8 %), and overall accuracy (94.8 %) in determining the etiology of small cervical lymph nodes. Conclusion: FNA cytology is suitable for small lesions inaccessible by CNB and provides a diagnostic basis for implementing clinically appropriate treatment measures.

8.
Nat Commun ; 15(1): 3399, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38649376

ABSTRACT

The van der Waals antiferromagnetic topological insulator MnBi2Te4 represents a promising platform for exploring the layer-dependent magnetism and topological states of matter. Recently observed discrepancies between magnetic and transport properties have aroused controversies concerning the topological nature of MnBi2Te4 in the ground state. In this article, we demonstrate that fabrication can induce mismatched even-odd layer dependent magnetotransport in few-layer MnBi2Te4. We perform a comprehensive study of the magnetotransport properties in 6- and 7-septuple-layer MnBi2Te4, and reveal that both even- and odd-number-layer device can show zero Hall plateau phenomena in zero magnetic field. Importantly, a statistical survey of the optical contrast in more than 200 MnBi2Te4 flakes reveals that the zero Hall plateau in odd-number-layer devices arises from the reduction of the effective thickness during the fabrication, a factor that was rarely noticed in previous studies of 2D materials. Our finding not only provides an explanation to the controversies regarding the discrepancy of the even-odd layer dependent magnetotransport in MnBi2Te4, but also highlights the critical issues concerning the fabrication and characterization of 2D material devices.

9.
Chin Med J Pulm Crit Care Med ; 2(1): 27-33, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38558961

ABSTRACT

Progressive lung fibrosis is characterised by dysregulated extracellular matrix (ECM) homeostasis. Understanding of disease pathogenesis remains limited and has prevented the development of effective treatments. While an abnormal wound healing response is strongly implicated in lung fibrosis initiation, factors that determine why fibrosis progresses rather than regular tissue repair occurs are not fully explained. Within human lung fibrosis there is evidence of altered epithelial and mesenchymal lung populations as well as cells undergoing epithelial-mesenchymal transition (EMT), a dynamic and reversible biological process by which epithelial cells lose their cell polarity and down-regulate cadherin-mediated cell-cell adhesion to gain migratory properties. This review will focus upon the role of EMT and dysregulated epithelial-mesenchymal crosstalk in progressive lung fibrosis.

10.
Natl Sci Rev ; 11(5): nwad249, 2024 May.
Article in English | MEDLINE | ID: mdl-38577674

ABSTRACT

Superconducting phase transitions in two dimensions lie beyond the description of the Ginzburg-Landau symmetry-breaking paradigm for three-dimensional superconductors. They are Berezinskii-Kosterlitz-Thouless (BKT) transitions of paired-electron condensate driven by the unbinding of topological excitations, i.e. vortices. The recently discovered monolayers of layered high-transition-temperature ([Formula: see text]) cuprate superconductor Bi2Sr2CaCu2O8+δ (Bi2212) meant that this 2D superconductor promised to be ideal for the study of unconventional superconductivity. But inhomogeneity posed challenges for distinguishing BKT physics from charge correlations in this material. Here, we utilize the phase sensitivity of scanning superconducting quantum interference device microscopy susceptometry to image the local magnetic response of underdoped Bi2212 from the monolayer to the bulk throughout its phase transition. The monolayer segregates into domains with independent phases at elevated temperatures below [Formula: see text]. Within a single domain, we find that the susceptibility oscillates with flux between diamagnetism and paramagnetism in a Fraunhofer-like pattern up to [Formula: see text]. The finite modulation period, as well as the broadening of the peaks when approaching [Formula: see text] from below, suggests well-defined vortices that are increasingly screened by the dissociation of vortex-antivortex plasma through a BKT transition. In the multilayers, the susceptibility oscillation differs in a small temperature regime below [Formula: see text], consistent with a dimensional crossover led by interlayer coupling. Serving as strong evidence for BKT transition in the bulk, we observe a sharp jump in phase stiffness and paramagnetism at small fields just below [Formula: see text]. These results unify the superconducting phase transitions from the monolayer to the bulk underdoped Bi2212, and can be collectively referred to as the BKT transition with interlayer coupling.

11.
Circ Genom Precis Med ; 17(2): e004397, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38563135

ABSTRACT

BACKGROUND: Basic scientists have used preclinical animal models to explore mechanisms driving human diseases for decades, resulting in thousands of publications, each supporting causative inferences. Despite substantial advances in the mechanistic construct of disease, there has been limited translation from individual studies to advances in clinical care. An integrated approach to these individual studies has the potential to improve translational success. METHODS: Using atherosclerosis as a test case, we extracted data from the 2 most common mouse models of atherosclerosis (ApoE [apolipoprotein E]-knockout and LDLR [low-density lipoprotein receptor]-knockout). We restricted analyses to manuscripts published in 2 well-established journals, Arteriosclerosis, Thrombosis, and Vascular Biology and Circulation, as of query in 2021. Predefined variables including experimental conditions, intervention, and outcomes were extracted from each publication to produce a preclinical atherosclerosis database. RESULTS: Extracted data include animal sex, diet, intervention type, and distinct plaque pathologies (size, inflammation, and lipid content). Procedures are provided to standardize data extraction, attribute interventions to specific genes, and transform the database for use with available transcriptomics software. The database integrates hundreds of genes, each directly tested in vivo for causation in a murine atherosclerosis model. The database is provided to allow the research community to perform integrated analyses that reflect the global impact of decades of atherosclerosis investigation. CONCLUSIONS: This database is provided as a resource for future interrogation of sub-data sets associated with distinct plaque pathologies, cell type, or sex. We also provide the methods and software needed to expand this data set and apply this approach to the extensive repository of peer-reviewed data utilizing preclinical models to interrogate mechanisms of diverse human diseases.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Mice , Humans , Animals , Atherosclerosis/pathology
13.
New Phytol ; 242(6): 2635-2651, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38634187

ABSTRACT

Endosperm is the main storage organ in cereal grain and determines grain yield and quality. The molecular mechanisms of heat shock proteins in regulating starch biosynthesis and endosperm development remain obscure. Here, we report a rice floury endosperm mutant flo24 that develops abnormal starch grains in the central starchy endosperm cells. Map-based cloning and complementation test showed that FLO24 encodes a heat shock protein HSP101, which is localized in plastids. The mutated protein FLO24T296I dramatically lost its ability to hydrolyze ATP and to rescue the thermotolerance defects of the yeast hsp104 mutant. The flo24 mutant develops more severe floury endosperm when grown under high-temperature conditions than normal conditions. And the FLO24 protein was dramatically induced at high temperature. FLO24 physically interacts with several key enzymes required for starch biosynthesis, including AGPL1, AGPL3 and PHO1. Combined biochemical and genetic evidence suggests that FLO24 acts cooperatively with HSP70cp-2 to regulate starch biosynthesis and endosperm development in rice. Our results reveal that FLO24 acts as an important regulator of endosperm development, which might function in maintaining the activities of enzymes involved in starch biosynthesis in rice.


Subject(s)
Endosperm , Gene Expression Regulation, Plant , Mutation , Oryza , Plant Proteins , Starch , Oryza/genetics , Oryza/metabolism , Oryza/growth & development , Endosperm/metabolism , Endosperm/growth & development , Starch/metabolism , Starch/biosynthesis , Plant Proteins/metabolism , Plant Proteins/genetics , Mutation/genetics , Protein Binding , Plastids/metabolism , Genetic Complementation Test , Adenosine Triphosphate/metabolism , Adenosine Triphosphate/biosynthesis , Thermotolerance , Transcription Factors
15.
Br J Cancer ; 130(11): 1841-1854, 2024 May.
Article in English | MEDLINE | ID: mdl-38553589

ABSTRACT

BACKGROUND: Despite the extensive study of MYCN-amplified neuroblastomas, there is a significant unmet clinical need in MYCN non-amplified cases. In particular, the extent of heterogeneity within the MYCN non-amplified population is unknown. METHODS: A total of 1566 samples from 16 datasets were identified in Gene Expression Omnibus (GEO) and ArrayExpress. Characterisation of the subtypes was analysed by ConsensusClusterPlus. Independent predictors for subgrouping were constructed from the single sample predictor based on the multiclassPairs package. Findings were verified using immunohistochemistry and CIBERSORTx analysis. RESULTS: We demonstrate that MYCN non-amplified neuroblastomas are heterogeneous and can be classified into 3 subgroups based on their transcriptional signatures. Within these groups, subgroup_2 has the worst prognosis and this group shows a 'MYCN' signature that is potentially induced by the overexpression of Aurora Kinase A (AURKA); whilst subgroup_3 is characterised by an 'inflamed' gene signature. The clinical implications of this subtype classification are significant, as each subtype demonstrates a unique prognosis and vulnerability to investigational therapies. A total of 420 genes were identified as independent subgroup predictors with average balanced accuracy of 0.93 and 0.84 for train and test datasets, respectively. CONCLUSION: We propose that transcriptional subtyping may enhance precision prognosis and therapy stratification for patients with MYCN non-amplified neuroblastomas.


Subject(s)
N-Myc Proto-Oncogene Protein , Neuroblastoma , Humans , Neuroblastoma/genetics , Neuroblastoma/classification , Neuroblastoma/pathology , Neuroblastoma/mortality , N-Myc Proto-Oncogene Protein/genetics , Prognosis , Aurora Kinase A/genetics , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic , Biomarkers, Tumor/genetics , Gene Amplification
16.
Pathogens ; 13(3)2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38535573

ABSTRACT

Campylobacter species, especially C. jejuni and C. coli, are the main zoonotic bacteria causing human gastroenteritis. A variety of Campylobacter species has been reported in wild birds, posing a potential avian-human transmission pathway. Currently, there has been little surveillance data on Campylobacter carriage in migratory birds in China. In the current work, fresh fecal droppings from individual migratory birds were collected at four bird wintering/stopover sites in China from May 2020 to March 2021. Nucleic acid was extracted and tested for Campylobacter with PCR-based methods. Overall, 73.8% (329/446) of the samples were positive for Campylobacter, demonstrating location and bird host specificity. Further speciation revealed the presence of C. jejuni, C. coli, C. lari, C. volucris, and an uncharacterized species, which all harbored a variety of virulence factors. Phylogenetic analysis performed on concatenated 16S rRNA-atpA-groEL genes elucidated their genetic relationship, demonstrating both inter- and intra-species diversity. The wide distribution and high diversity of Campylobacter spp. detected in migratory birds in China indicated potential transmission across territories. The existence of virulence factors in all of these species highlighted their public health importance and the necessity of monitoring and controlling Campylobacter and other pathogens carried by migratory birds.

17.
BMC Genomics ; 25(1): 132, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38302871

ABSTRACT

BACKGROUND: The U-box gene family encodes E3 ubiquitin ligases involved in plant hormone signaling pathways and abiotic stress responses. However, there has yet to be a comprehensive analysis of the U-box gene family in maize (Zea mays L.) and its responses to abiotic stress. RESULTS: In this study, 85 U-box family proteins were identified in maize and were classified into four subfamilies based on phylogenetic analysis. In addition to the conserved U-box domain, we identified additional functional domains, including Pkinase, ARM, KAP and Tyr domains, by analyzing the conserved motifs and gene structures. Chromosomal localization and collinearity analysis revealed that gene duplications may have contributed to the expansion and evolution of the U-box gene family. GO annotation and KEGG pathway enrichment analysis identified a total of 105 GO terms and 21 KEGG pathways that were notably enriched, including ubiquitin-protein transferase activity, ubiquitin conjugating enzyme activity and ubiquitin-mediated proteolysis pathway. Tissue expression analysis showed that some ZmPUB genes were specifically expressed in certain tissues and that this could be due to their functions. In addition, RNA-seq data for maize seedlings under salt stress revealed 16 stress-inducible plant U-box genes, of which 10 genes were upregulated and 6 genes were downregulated. The qRT-PCR results for genes responding to abiotic stress were consistent with the transcriptome analysis. Among them, ZmPUB13, ZmPUB18, ZmPUB19 and ZmPUB68 were upregulated under all three abiotic stress conditions. Subcellular localization analysis showed that ZmPUB19 and ZmPUB59 were located in the nucleus. CONCLUSIONS: Overall, our study provides a comprehensive analysis of the U-box gene family in maize and its responses to abiotic stress, suggesting that U-box genes play an important role in the stress response and providing insights into the regulatory mechanisms underlying the response to abiotic stress in maize.


Subject(s)
Ubiquitin-Protein Ligases , Zea mays , Zea mays/metabolism , Phylogeny , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Gene Expression Profiling , Stress, Physiological/genetics , Ubiquitins/genetics , Gene Expression Regulation, Plant , Plant Proteins/metabolism , Multigene Family
18.
Proc Natl Acad Sci U S A ; 121(10): e2309957121, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38422022

ABSTRACT

Hypoxia signaling influences tumor development through both cell-intrinsic and -extrinsic pathways. Inhibiting hypoxia-inducible factor (HIF) function has recently been approved as a cancer treatment strategy. Hence, it is important to understand how regulators of HIF may affect tumor growth under physiological conditions. Here we report that in aging mice factor-inhibiting HIF (FIH), one of the most studied negative regulators of HIF, is a haploinsufficient suppressor of spontaneous B cell lymphomas, particular pulmonary B cell lymphomas. FIH deficiency alters immune composition in aged mice and creates a tumor-supportive immune environment demonstrated in syngeneic mouse tumor models. Mechanistically, FIH-defective myeloid cells acquire tumor-supportive properties in response to signals secreted by cancer cells or produced in the tumor microenvironment with enhanced arginase expression and cytokine-directed migration. Together, these data demonstrate that under physiological conditions, FIH plays a key role in maintaining immune homeostasis and can suppress tumorigenesis through a cell-extrinsic pathway.


Subject(s)
Lymphoma, B-Cell , Repressor Proteins , Animals , Mice , Hypoxia/metabolism , Mixed Function Oxygenases/metabolism , Repressor Proteins/metabolism , Tumor Microenvironment
19.
Genes Dis ; 11(3): 101065, 2024 May.
Article in English | MEDLINE | ID: mdl-38222900

ABSTRACT

The factors that determine fibrosis progression or normal tissue repair are largely unknown. We previously demonstrated that autophagy inhibition-mediated epithelial-mesenchymal transition (EMT) in human alveolar epithelial type II (ATII) cells augments local myofibroblast differentiation in pulmonary fibrosis by paracrine signalling. Here, we report that liver kinase B1 (LKB1) inactivation in ATII cells inhibits autophagy and induces EMT as a consequence. In IPF lungs, this is caused by downregulation of CAB39L, a key subunit within the LKB1 complex. 3D co-cultures of ATII cells and MRC5 lung fibroblasts coupled with RNA sequencing (RNA-seq) confirmed that paracrine signalling between LKB1-depleted ATII cells and fibroblasts augmented myofibroblast differentiation. Together these data suggest that reduced autophagy caused by LKB1 inhibition can induce EMT in ATII cells and contribute to fibrosis via aberrant epithelial-fibroblast crosstalk.

20.
Plant Cell ; 36(5): 1892-1912, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38262703

ABSTRACT

In cereal grains, starch is synthesized by the concerted actions of multiple enzymes on the surface of starch granules within the amyloplast. However, little is known about how starch-synthesizing enzymes access starch granules, especially for amylopectin biosynthesis. Here, we show that the rice (Oryza sativa) floury endosperm9 (flo9) mutant is defective in amylopectin biosynthesis, leading to grains exhibiting a floury endosperm with a hollow core. Molecular cloning revealed that FLO9 encodes a plant-specific protein homologous to Arabidopsis (Arabidopsis thaliana) LIKE EARLY STARVATION1 (LESV). Unlike Arabidopsis LESV, which is involved in starch metabolism in leaves, OsLESV is required for starch granule initiation in the endosperm. OsLESV can directly bind to starch by its C-terminal tryptophan (Trp)-rich region. Cellular and biochemical evidence suggests that OsLESV interacts with the starch-binding protein FLO6, and loss-of-function mutations of either gene impair ISOAMYLASE1 (ISA1) targeting to starch granules. Genetically, OsLESV acts synergistically with FLO6 to regulate starch biosynthesis and endosperm development. Together, our results identify OsLESV-FLO6 as a non-enzymatic molecular module responsible for ISA1 localization on starch granules, and present a target gene for use in biotechnology to control starch content and composition in rice endosperm.


Subject(s)
Endosperm , Gene Expression Regulation, Plant , Oryza , Plant Proteins , Starch , Oryza/genetics , Oryza/metabolism , Oryza/growth & development , Endosperm/metabolism , Endosperm/genetics , Starch/metabolism , Starch/biosynthesis , Plant Proteins/metabolism , Plant Proteins/genetics , Amylopectin/metabolism , Mutation , Plants, Genetically Modified
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