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1.
Cell ; 176(5): 1113-1127.e16, 2019 02 21.
Article in English | MEDLINE | ID: mdl-30712867

ABSTRACT

Activating mutations in NRAS account for 20%-30% of melanoma, but despite decades of research and in contrast to BRAF, no effective anti-NRAS therapies have been forthcoming. Here, we identify a previously uncharacterized serine/threonine kinase STK19 as a novel NRAS activator. STK19 phosphorylates NRAS to enhance its binding to its downstream effectors and promotes oncogenic NRAS-mediated melanocyte malignant transformation. A recurrent D89N substitution in STK19 whose alterations were identified in 25% of human melanomas represents a gain-of-function mutation that interacts better with NRAS to enhance melanocyte transformation. STK19D89N knockin leads to skin hyperpigmentation and promotes NRASQ61R-driven melanomagenesis in vivo. Finally, we developed ZT-12-037-01 (1a) as a specific STK19-targeted inhibitor and showed that it effectively blocks oncogenic NRAS-driven melanocyte malignant transformation and melanoma growth in vitro and in vivo. Together, our findings provide a new and viable therapeutic strategy for melanomas harboring NRAS mutations.


Subject(s)
GTP Phosphohydrolases/metabolism , Melanoma/genetics , Membrane Proteins/metabolism , Nuclear Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Animals , Cell Line, Tumor , Cell Transformation, Neoplastic , Female , HEK293 Cells , Humans , Melanocytes/metabolism , Melanoma/metabolism , Mice , Mice, Inbred C57BL , Mice, Nude , Mutation , Phosphorylation , Proto-Oncogene Proteins B-raf/metabolism , Signal Transduction , Skin Neoplasms/genetics
2.
Mol Cell ; 82(21): 4099-4115.e9, 2022 11 03.
Article in English | MEDLINE | ID: mdl-36208627

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive hepatic lipid accumulation, which can progress to nonalcoholic steatohepatitis (NASH). Histone deacetylase Sirtuin 6 (SIRT6) regulates NAFLD by regulating metabolism-related gene expression, but an extrachromosomal role for SIRT6 in NAFLD development remains elusive. We investigated whether SIRT6 functions on NAFLD in the cytoplasm. We found that SIRT6 binds saturated fatty acids, especially palmitic acid. This binding leads to its nuclear export, where it deacetylates long-chain acyl-CoA synthase 5 (ACSL5), thereby facilitating fatty acid oxidation. High-fat diet-induced NAFLD is suppressed by ACSL5 hepatic overexpression but is exacerbated by its depletion. As confirmation, overexpression of a deacetylated ACSL5 mimic attenuated NAFLD in Sirt6 liver-specific knockout mice. Moreover, NASH-hepatic tissues from both patients and diet-fed mice exhibited significantly reduced cytoplasmic SIRT6 levels and increased ACSL5 acetylation. The SIRT6/ACSL5 signaling pathway has a critical role in NAFLD progression and might constitute an avenue for therapeutic intervention.


Subject(s)
Non-alcoholic Fatty Liver Disease , Sirtuins , Mice , Animals , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/metabolism , Acyl Coenzyme A/metabolism , Mice, Inbred C57BL , Liver/metabolism , Lipid Metabolism , Mice, Knockout , Fatty Acids/metabolism , Sirtuins/genetics , Sirtuins/metabolism , Cytoplasm/metabolism
3.
EMBO J ; 43(12): 2453-2485, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38719994

ABSTRACT

Double-strand breaks (DSBs) are the most lethal form of DNA damage. Transcriptional activity at DSBs, as well as transcriptional repression around DSBs, are both required for efficient DNA repair. The chromatin landscape defines and coordinates these two opposing events. However, how the open and condensed chromatin architecture is regulated remains unclear. Here, we show that the GATAD2B-NuRD complex associates with DSBs in a transcription- and DNA:RNA hybrid-dependent manner, to promote histone deacetylation and chromatin condensation. This activity establishes a spatio-temporal boundary between open and closed chromatin, which is necessary for the correct termination of DNA end resection. The lack of the GATAD2B-NuRD complex leads to chromatin hyperrelaxation and extended DNA end resection, resulting in homologous recombination (HR) repair failure. Our results suggest that the GATAD2B-NuRD complex is a key coordinator of the dynamic interplay between transcription and the chromatin landscape, underscoring its biological significance in the RNA-dependent DNA damage response.


Subject(s)
Chromatin , DNA Breaks, Double-Stranded , Mi-2 Nucleosome Remodeling and Deacetylase Complex , Chromatin/metabolism , Chromatin/genetics , Mi-2 Nucleosome Remodeling and Deacetylase Complex/metabolism , Mi-2 Nucleosome Remodeling and Deacetylase Complex/genetics , RNA/metabolism , RNA/genetics , DNA Damage , DNA/metabolism , DNA/genetics , Animals , Humans , Transcription, Genetic , DNA Repair , Mice
4.
Mol Cell ; 75(6): 1299-1314.e6, 2019 09 19.
Article in English | MEDLINE | ID: mdl-31353207

ABSTRACT

MRE11 nuclease forms a trimeric complex (MRN) with RAD50 and NBS1 and plays a central role in preventing genomic instability. When DNA double-strand breaks (DSBs) occur, MRN is quickly recruited to the damage site and initiates DNA end resection; accordingly, MRE11 must be tightly regulated to avoid inefficient repair or nonspecific resection. Here, we show that MRE11 and RAD50 form a complex (MRC) with C1QBP, which stabilizes MRE11/RAD50, while inhibiting MRE11 nuclease activity by preventing its binding to DNA or chromatin. Upon DNA damage, ATM phosphorylates MRE11-S676/S678 to quickly dissociate the MRC complex. Either excess or insufficient C1QBP impedes the recruitment of MRE11 to DSBs and impairs the DNA damage response. C1QBP is highly expressed in breast cancer and positively correlates with MRE11 expression, and the inhibition of C1QBP enhances tumor regression with chemotherapy. By influencing MRE11 at multiple levels, C1QBP is, thus, an important player in the DNA damage response.


Subject(s)
Acid Anhydride Hydrolases/metabolism , Carrier Proteins/metabolism , Cell Cycle Proteins/metabolism , DNA-Binding Proteins/metabolism , Homologous Recombination , MRE11 Homologue Protein/metabolism , Mitochondrial Proteins/metabolism , Multiprotein Complexes/metabolism , Nuclear Proteins/metabolism , Acid Anhydride Hydrolases/genetics , Animals , Carrier Proteins/genetics , Cell Cycle Proteins/genetics , DNA-Binding Proteins/genetics , HEK293 Cells , HeLa Cells , Humans , MRE11 Homologue Protein/genetics , Mitochondrial Proteins/genetics , Multiprotein Complexes/genetics , Nuclear Proteins/genetics , Protein Stability , Sf9 Cells , Spodoptera
5.
Mol Cell ; 74(6): 1250-1263.e6, 2019 06 20.
Article in English | MEDLINE | ID: mdl-31054974

ABSTRACT

Alternative pre-mRNA-splicing-induced post-transcriptional gene expression regulation is one of the pathways for tumors maintaining proliferation rates accompanying the malignant phenotype under stress. Here, we uncover a list of hyperacetylated proteins in the context of acutely reduced Acetyl-CoA levels under nutrient starvation. PHF5A, a component of U2 snRNPs, can be acetylated at lysine 29 in response to multiple cellular stresses, which is dependent on p300. PHF5A acetylation strengthens the interaction among U2 snRNPs and affects global pre-mRNA splicing pattern and extensive gene expression. PHF5A hyperacetylation-induced alternative splicing stabilizes KDM3A mRNA and promotes its protein expression. Pathologically, PHF5A K29 hyperacetylation and KDM3A upregulation axis are correlated with poor prognosis of colon cancer. Our findings uncover a mechanism of an anti-stress pathway through which acetylation on PHF5A promotes the cancer cells' capacity for stress resistance and consequently contributes to colon carcinogenesis.


Subject(s)
Alternative Splicing , Carcinogenesis/genetics , Colorectal Neoplasms/genetics , Gene Expression Regulation, Neoplastic , Jumonji Domain-Containing Histone Demethylases/genetics , RNA-Binding Proteins/genetics , Trans-Activators/genetics , Acetyl Coenzyme A/deficiency , Acetylation , Animals , Carcinogenesis/metabolism , Carcinogenesis/pathology , Cell Movement , Cell Proliferation , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , HCT116 Cells , Humans , Jumonji Domain-Containing Histone Demethylases/antagonists & inhibitors , Jumonji Domain-Containing Histone Demethylases/metabolism , MCF-7 Cells , Male , Mice , Mice, Nude , Prognosis , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , RNA-Binding Proteins/antagonists & inhibitors , RNA-Binding Proteins/metabolism , Ribonucleoprotein, U2 Small Nuclear/genetics , Ribonucleoprotein, U2 Small Nuclear/metabolism , Signal Transduction , Survival Analysis , Trans-Activators/antagonists & inhibitors , Trans-Activators/metabolism , Xenograft Model Antitumor Assays , p300-CBP Transcription Factors/genetics , p300-CBP Transcription Factors/metabolism
6.
Proc Natl Acad Sci U S A ; 121(35): e2320804121, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39172790

ABSTRACT

Breast Cancer Type 1 Susceptibility Protein (BRCA1) is a tumor-suppressor protein that regulates various cellular pathways, including those that are essential for preserving genome stability. One essential mechanism involves a BRCA1-A complex that is recruited to double-strand breaks (DSBs) by RAP80 before initiating DNA damage repair (DDR). How RAP80 itself is recruited to DNA damage sites, however, is unclear. Here, we demonstrate an intrinsic correlation between a methyltransferase DOT1L-mediated RAP80 methylation and BRCA1-A complex chromatin recruitment that occurs during cancer cell radiotherapy resistance. Mechanistically, DOT1L is quickly recruited onto chromatin and methylates RAP80 at multiple lysines in response to DNA damage. Methylated RAP80 is then indispensable for binding to ubiquitinated H2A and subsequently triggering BRCA1-A complex recruitment onto DSBs. Importantly, DOT1L-catalyzed RAP80 methylation and recruitment of BRCA1 have clinical relevance, as inhibition of DOT1L or RAP80 methylation seems to enhance the radiosensitivity of cancer cells both in vivo and in vitro. These data reveal a crucial role for DOT1L in DDR through initiating recruitment of RAP80 and BRCA1 onto chromatin and underscore a therapeutic strategy based on targeting DOT1L to overcome tumor radiotherapy resistance.


Subject(s)
BRCA1 Protein , DNA Repair , Histone Chaperones , Histone-Lysine N-Methyltransferase , Animals , Humans , Mice , BRCA1 Protein/metabolism , BRCA1 Protein/genetics , Cell Line, Tumor , Chromatin/metabolism , DNA Breaks, Double-Stranded , DNA Methylation , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , Histone Chaperones/metabolism , Histone Chaperones/genetics , Histone-Lysine N-Methyltransferase/metabolism , Histone-Lysine N-Methyltransferase/genetics , Methylation , Methyltransferases/metabolism , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Radiation Tolerance/genetics
7.
Brief Bioinform ; 25(2)2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38499497

ABSTRACT

The escalating drug addiction crisis in the United States underscores the urgent need for innovative therapeutic strategies. This study embarked on an innovative and rigorous strategy to unearth potential drug repurposing candidates for opioid and cocaine addiction treatment, bridging the gap between transcriptomic data analysis and drug discovery. We initiated our approach by conducting differential gene expression analysis on addiction-related transcriptomic data to identify key genes. We propose a novel topological differentiation to identify key genes from a protein-protein interaction network derived from DEGs. This method utilizes persistent Laplacians to accurately single out pivotal nodes within the network, conducting this analysis in a multiscale manner to ensure high reliability. Through rigorous literature validation, pathway analysis and data-availability scrutiny, we identified three pivotal molecular targets, mTOR, mGluR5 and NMDAR, for drug repurposing from DrugBank. We crafted machine learning models employing two natural language processing (NLP)-based embeddings and a traditional 2D fingerprint, which demonstrated robust predictive ability in gauging binding affinities of DrugBank compounds to selected targets. Furthermore, we elucidated the interactions of promising drugs with the targets and evaluated their drug-likeness. This study delineates a multi-faceted and comprehensive analytical framework, amalgamating bioinformatics, topological data analysis and machine learning, for drug repurposing in addiction treatment, setting the stage for subsequent experimental validation. The versatility of the methods we developed allows for applications across a range of diseases and transcriptomic datasets.


Subject(s)
Drug Repositioning , Transcriptome , United States , Drug Repositioning/methods , Reproducibility of Results , Gene Expression Profiling , Computational Biology/methods
8.
J Neurosci ; 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39227158

ABSTRACT

Cochlear hair cells (HCs) sense sound waves and allow us to hear. Loss of HCs will cause irreversible sensorineural hearing loss. It is well known that DNA damage repair plays a critical role in protecting cells in many organs. However, how HCs respond to DNA damage and how defective DNA damage repair contributes to hearing loss remain elusive.In this study, we showed that cisplatin induced DNA damage in outer hair cells (OHCs) and promoted OHC loss, leading to hearing loss in mice of either sex. Cisplatin induced the expression of Brca1, a DNA damage repair factor, in OHCs. Deficiency of Brca1 induced OHC and hearing loss, and further promoted cisplatin-induced DNA damage in OHCs, accelerating OHC loss. This study provides the first in vivo evidence demonstrating that cisplatin mainly induces DNA damage in OHCs and that BRCA1 promotes repair of DNA damage in OHCs and prevents hearing loss. Our findings not only demonstrate that DNA-damage inducible agent generates DNA damage in postmitotic HCs, but also suggest that DNA repair factors, like BRCA1, protect postmitotic HCs from DNA-damage induced cell death and hearing loss.Significance statement Sensorineural hearing loss is the most severe hearing loss caused by irreversible loss of cochlear hair cells. Hair cells are vulnerable to aging and ototoxic drug. Though DNA damage repair plays a critical role in protecting cells in many organs, it is poorly understood how DNA damage is repaired in hair cells. This study provides the first in vivo evidence demonstrating that cisplatin mainly induces DNA damage in outer hair cells and that BRCA1 promotes repair of DNA damage in outer hair cells and prevents outer hair cell loss as well as hearing loss.

9.
J Biol Chem ; : 107768, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39270819

ABSTRACT

Basal-like breast cancer may originate from luminal epithelial or cancerous cells. Inadequately repaired DNA damage impairs luminal differentiation and promotes aberrant luminal to basal trans-differentiation in mammary epithelial cells (MECs). Ubiquitin-specific peptidase 11 (USP11), a deubiquitinase, plays a critical role in DNA damage repair. The role of USP11 in controlling mammary cell differentiation and tumorigenesis remains poorly understood. We generated Usp11 knockout mice and breast cancer cell lines expressing wild-type (WT) and mutant form of USP11. By using these mutant mice, cell lines, and human USP11-deficient and -proficient breast cancer tissues, we tested how USP11 controls mammary cell fate. We generated Usp11 knock-out mice and found that deletion of Usp11 reduced the expression of E-cadherin and promoted DNA damage in MECs. Overexpression of WT USP11, but not a deubiquitinase-inactive mutant form of USP11, promoted luminal differentiation, enhanced DNA damage repair, and suppressed tumorigenesis in mice. Mechanistically, we found that USP11 enhanced the protein expression of E-cadherin dependent on its deubiquitinase activity, and that USP11 deubiquitinated E-cadherin at K738. We discovered that USP11 bound to E-cadherin through its C-terminal region. In human breast cancers, expression of USP11 was positively correlated with that of E-cadherin, and high USP11 predicted better recurrence-free survival. Our findings provide compelling genetic and biochemical evidence that USP11 not only promotes DNA damage repair but also deubiquitinates E-cadherin and maintains the luminal feature of mammary tumor cells, thereby suppressing luminal breast cancer.

10.
Mol Biol Evol ; 41(2)2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38243850

ABSTRACT

Local adaptation is critical in speciation and evolution, yet comprehensive studies on proximate and ultimate causes of local adaptation are generally scarce. Here, we integrated field ecological experiments, genome sequencing, and genetic verification to demonstrate both driving forces and molecular mechanisms governing local adaptation of body coloration in a lizard from the Qinghai-Tibet Plateau. We found dark lizards from the cold meadow population had lower spectrum reflectance but higher melanin contents than light counterparts from the warm dune population. Additionally, the colorations of both dark and light lizards facilitated the camouflage and thermoregulation in their respective microhabitat simultaneously. More importantly, by genome resequencing analysis, we detected a novel mutation in Tyrp1 that underpinned this color adaptation. The allele frequencies at the site of SNP 459# in the gene of Tyrp1 are 22.22% G/C and 77.78% C/C in dark lizards and 100% G/G in light lizards. Model-predicted structure and catalytic activity showed that this mutation increased structure flexibility and catalytic activity in enzyme TYRP1, and thereby facilitated the generation of eumelanin in dark lizards. The function of the mutation in Tyrp1 was further verified by more melanin contents and darker coloration detected in the zebrafish injected with the genotype of Tyrp1 from dark lizards. Therefore, our study demonstrates that a novel mutation of a major melanin-generating gene underpins skin color variation co-selected by camouflage and thermoregulation in a lizard. The resulting strong selection may reinforce adaptive genetic divergence and enable the persistence of adjacent populations with distinct body coloration.


Subject(s)
Lizards , Melanins , Animals , Melanins/genetics , Lizards/genetics , Zebrafish , Body Temperature Regulation/genetics , Skin Pigmentation/genetics , Color
11.
Brief Bioinform ; 24(5)2023 09 20.
Article in English | MEDLINE | ID: mdl-37580175

ABSTRACT

Protein engineering is an emerging field in biotechnology that has the potential to revolutionize various areas, such as antibody design, drug discovery, food security, ecology, and more. However, the mutational space involved is too vast to be handled through experimental means alone. Leveraging accumulative protein databases, machine learning (ML) models, particularly those based on natural language processing (NLP), have considerably expedited protein engineering. Moreover, advances in topological data analysis (TDA) and artificial intelligence-based protein structure prediction, such as AlphaFold2, have made more powerful structure-based ML-assisted protein engineering strategies possible. This review aims to offer a comprehensive, systematic, and indispensable set of methodological components, including TDA and NLP, for protein engineering and to facilitate their future development.


Subject(s)
Artificial Intelligence , Protein Engineering , Natural Language Processing , Antibodies , Data Analysis
12.
Brief Bioinform ; 24(3)2023 05 19.
Article in English | MEDLINE | ID: mdl-37080771

ABSTRACT

Single-cell RNA sequencing (scRNA-seq) has significantly accelerated the experimental characterization of distinct cell lineages and types in complex tissues and organisms. Cell-type annotation is of great importance in most of the scRNA-seq analysis pipelines. However, manual cell-type annotation heavily relies on the quality of scRNA-seq data and marker genes, and therefore can be laborious and time-consuming. Furthermore, the heterogeneity of scRNA-seq datasets poses another challenge for accurate cell-type annotation, such as the batch effect induced by different scRNA-seq protocols and samples. To overcome these limitations, here we propose a novel pipeline, termed TripletCell, for cross-species, cross-protocol and cross-sample cell-type annotation. We developed a cell embedding and dimension-reduction module for the feature extraction (FE) in TripletCell, namely TripletCell-FE, to leverage the deep metric learning-based algorithm for the relationships between the reference gene expression matrix and the query cells. Our experimental studies on 21 datasets (covering nine scRNA-seq protocols, two species and three tissues) demonstrate that TripletCell outperformed state-of-the-art approaches for cell-type annotation. More importantly, regardless of protocols or species, TripletCell can deliver outstanding and robust performance in annotating different types of cells. TripletCell is freely available at https://github.com/liuyan3056/TripletCell. We believe that TripletCell is a reliable computational tool for accurately annotating various cell types using scRNA-seq data and will be instrumental in assisting the generation of novel biological hypotheses in cell biology.


Subject(s)
Algorithms , Single-Cell Analysis , Single-Cell Analysis/methods , Sequence Analysis, RNA/methods , Gene Expression Profiling/methods , Cluster Analysis
13.
Chem Rev ; 123(13): 8736-8780, 2023 07 12.
Article in English | MEDLINE | ID: mdl-37384816

ABSTRACT

Small data are often used in scientific and engineering research due to the presence of various constraints, such as time, cost, ethics, privacy, security, and technical limitations in data acquisition. However, big data have been the focus for the past decade, small data and their challenges have received little attention, even though they are technically more severe in machine learning (ML) and deep learning (DL) studies. Overall, the small data challenge is often compounded by issues, such as data diversity, imputation, noise, imbalance, and high-dimensionality. Fortunately, the current big data era is characterized by technological breakthroughs in ML, DL, and artificial intelligence (AI), which enable data-driven scientific discovery, and many advanced ML and DL technologies developed for big data have inadvertently provided solutions for small data problems. As a result, significant progress has been made in ML and DL for small data challenges in the past decade. In this review, we summarize and analyze several emerging potential solutions to small data challenges in molecular science, including chemical and biological sciences. We review both basic machine learning algorithms, such as linear regression, logistic regression (LR), k-nearest neighbor (KNN), support vector machine (SVM), kernel learning (KL), random forest (RF), and gradient boosting trees (GBT), and more advanced techniques, including artificial neural network (ANN), convolutional neural network (CNN), U-Net, graph neural network (GNN), Generative Adversarial Network (GAN), long short-term memory (LSTM), autoencoder, transformer, transfer learning, active learning, graph-based semi-supervised learning, combining deep learning with traditional machine learning, and physical model-based data augmentation. We also briefly discuss the latest advances in these methods. Finally, we conclude the survey with a discussion of promising trends in small data challenges in molecular science.


Subject(s)
Artificial Intelligence , Machine Learning , Algorithms , Electric Power Supplies , Neural Networks, Computer
14.
Nucleic Acids Res ; 51(17): 9166-9182, 2023 09 22.
Article in English | MEDLINE | ID: mdl-37503842

ABSTRACT

Histone deacetylase 6 (HDAC6) mediates DNA damage signaling by regulating the mismatch repair and nucleotide excision repair pathways. Whether HDAC6 also mediates DNA double-strand break (DSB) repair is unclear. Here, we report that HDAC6 negatively regulates DSB repair in an enzyme activity-independent manner. In unstressed cells, HDAC6 interacts with H2A/H2A.X to prevent its interaction with the E3 ligase RNF168. Upon sensing DSBs, RNF168 rapidly ubiquitinates HDAC6 at lysine 116, leading to HDAC6 proteasomal degradation and a restored interaction between RNF168 and H2A/H2A.X. H2A/H2A.X is ubiquitinated by RNF168, precipitating the recruitment of DSB repair factors (including 53BP1 and BRCA1) to chromatin and subsequent DNA repair. These findings reveal novel regulatory machinery based on an HDAC6-RNF168 axis that regulates the H2A/H2A.X ubiquitination status. Interfering with this axis might be leveraged to disrupt a key mechanism of cancer cell resistance to genotoxic damage and form a potential therapeutic strategy for cancer.


Subject(s)
DNA Repair , Humans , Cell Line, Tumor , DNA Damage , Histone Deacetylase 6/genetics , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination
15.
BMC Biol ; 22(1): 85, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38627785

ABSTRACT

BACKGROUND: Inadequate DNA damage repair promotes aberrant differentiation of mammary epithelial cells. Mammary luminal cell fate is mainly determined by a few transcription factors including GATA3. We previously reported that GATA3 functions downstream of BRCA1 to suppress aberrant differentiation in breast cancer. How GATA3 impacts DNA damage repair preventing aberrant cell differentiation in breast cancer remains elusive. We previously demonstrated that loss of p18, a cell cycle inhibitor, in mice induces luminal-type mammary tumors, whereas depletion of either Brca1 or Gata3 in p18 null mice leads to basal-like breast cancers (BLBCs) with activation of epithelial-mesenchymal transition (EMT). We took advantage of these mutant mice to examine the role of Gata3 as well as the interaction of Gata3 and Brca1 in DNA damage repair in mammary tumorigenesis. RESULTS: Depletion of Gata3, like that of Brca1, promoted DNA damage accumulation in breast cancer cells in vitro and in basal-like breast cancers in vivo. Reconstitution of Gata3 improved DNA damage repair in Brca1-deficient mammary tumorigenesis. Overexpression of GATA3 promoted homologous recombination (HR)-mediated DNA damage repair and restored HR efficiency of BRCA1-deficient cells. Depletion of Gata3 sensitized tumor cells to PARP inhibitor (PARPi), and reconstitution of Gata3 enhanced resistance of Brca1-deficient tumor cells to PARP inhibitor. CONCLUSIONS: These results demonstrate that Gata3 functions downstream of BRCA1 to promote DNA damage repair and suppress dedifferentiation in mammary tumorigenesis and progression. Our findings suggest that PARP inhibitors are effective for the treatment of GATA3-deficient BLBCs.


Subject(s)
Mammary Neoplasms, Animal , Poly(ADP-ribose) Polymerase Inhibitors , Animals , Mice , Cell Line, Tumor , Cell Transformation, Neoplastic/genetics , DNA Damage , DNA Repair , Mammary Neoplasms, Animal/genetics , Mammary Neoplasms, Animal/pathology , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology
16.
Genomics ; : 110937, 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39278335

ABSTRACT

Reproductive traits are vital economic parameters in goat production, and boosting the reproductive capacity of breeding rams is crucial for enhancing the profitability of goat farming. Currently, research on the reproductive performance of Qianbei Ma goats mainly centers on investigating mechanisms associated with prolificacy and estrous ovulation in ewes, with limited emphasis on ram reproductive aspects. This study used scanning electron microscopy and enzyme-linked immunosorbent assay (ELISA) to profile the morphology of testis and the dynamic changes of Luteinizing Hormone (LH), Follicle-Stimulating Hormone (FSH), and Testosterone (T) in serum at different developmental stages of Qianbei Ma goats. Meanwhile, transcriptome sequencing technology was used to investigate the mRNA expression patterns in testicular tissues at different developmental stages: newborn (0 M), puberty (6 M), sexual maturity (12 M), and physical maturity (18 M). The results showed that the diameter, circumference, and area of the testicular seminiferous tubules gradually increased with age. The levels of T and LH in serum significantly increased from 0 to 6 months after birth (p < 0.05), followed by a stabilization of T levels and a significant decrease in LH levels (p < 0.05). Meanwhile, FSH shows a decreasing trend between 0 and 18 months after birth. A total of 26,437 differentially expressed genes were identified in 6 comparison groups, which involve various biological processes such as immunity, growth, metabolism, development, and reproduction, and are significantly enriched in signaling pathways related to testicular development and spermatogenesis. WGCNA analysis identified 6 regions significantly associated with testicular development and spermatogenesis, and selected 320 genes for constructing a PPI network. Ten candidate genes related to testicular development and spermatogenesis were identified, including TP53, PLK4, RPS9, PFN4, ACTB, CYP17A1, GPX4, CLDN1, AMH and DHH. Of these, the CYP17A1 gene promotes interstitial cell proliferation, and promotes T synthesis. This study provides a theoretical basis and data support for promoting efficient breeding of goats and early breeding of excellent male goats.

17.
Biophys J ; 123(17): 2807-2814, 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-38356263

ABSTRACT

Electrostatics is of paramount importance to chemistry, physics, biology, and medicine. The Poisson-Boltzmann (PB) theory is a primary model for electrostatic analysis. However, it is highly challenging to compute accurate PB electrostatic solvation free energies for macromolecules due to the nonlinearity, dielectric jumps, charge singularity, and geometric complexity associated with the PB equation. The present work introduces a PB-based machine learning (PBML) model for biomolecular electrostatic analysis. Trained with the second-order accurate MIBPB solver, the proposed PBML model is found to be more accurate and faster than several eminent PB solvers in electrostatic analysis. The proposed PBML model can provide highly accurate PB electrostatic solvation free energy of new biomolecules or new conformations generated by molecular dynamics with much reduced computational cost.


Subject(s)
Machine Learning , Static Electricity , Molecular Dynamics Simulation , Poisson Distribution , Thermodynamics
18.
Plant J ; 116(5): 1309-1324, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37614043

ABSTRACT

Citrus production is severely threatened by the devastating Huanglongbing (HLB) disease globally. By studying and analyzing the defensive behaviors of an HLB-tolerant citrus cultivar 'Shatangju', we discovered that citrus can sense Candidatus Liberibacter asiaticus (CLas) infection and induce immune responses against HLB, which can be further strengthened by both endogenously produced and exogenously applied methyl salicylate (MeSA). This immune circuit is turned on by an miR2977-SAMT (encoding a citrus Salicylate [SA] O-methyltransferase) cascade, by which CLas infection leads to more in planta MeSA production and aerial emission. We provided both transgenic and multi-year trail evidences that MeSA is an effective community immune signal. Ambient MeSA accumulation and foliage application can effectively induce defense gene expression and significantly boost citrus performance. We also found that miRNAs are battle fields between citrus and CLas, and about 30% of the differential gene expression upon CLas infection are regulated by miRNAs. Furthermore, CLas hijacks host key processes by manipulating key citrus miRNAs, and citrus employs miRNAs that coordinately regulate defense-related genes. Based on our results, we proposed that miRNAs and associated components are key targets for engineering or breeding resistant citrus varieties. We anticipate that MeSA-based management, either induced expression or external application, would be a promising tool for HLB control.


Subject(s)
Citrus , MicroRNAs , Rhizobiaceae , Citrus/physiology , Plant Diseases , Plant Breeding , Salicylates/metabolism , Liberibacter/genetics , MicroRNAs/genetics , MicroRNAs/metabolism
19.
Immunology ; 172(3): 375-391, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38471664

ABSTRACT

Persistent human papillomavirus (HPV) infection is associated with multiple malignancies. Developing therapeutic vaccines to eliminate HPV-infected and malignant cells holds significant value. In this study, we introduced a lipid nanoparticle encapsulated mRNA vaccine expressing tHA-mE7-mE6. Mutations were introduced into E6 and E7 of HPV to eliminate their tumourigenicity. A truncated influenza haemagglutinin protein (tHA), which binds to the CD209 receptor on the surface of dendritic cells (DCs), was fused with mE7-mE6 in order to allow efficient uptake of antigen by antigen presenting cells. The tHA-mE7-mE6 (mRNA) showed higher therapeutic efficacy than mE7-mE6 (mRNA) in an E6 and E7+ tumour model. The treatment resulted in complete tumour regression and prevented tumour formation. Strong CD8+ T-cell immune response was induced, contributing to preventing and curing of E6 and E7+ tumour. Antigen-specific CD8+ T were found in spleens, peripheral blood and in tumours. In addition, the tumour infiltration of DC and NK cells were increased post therapy. In conclusion, this study described a therapeutic mRNA vaccine inducing strong anti-tumour immunity in peripheral and in tumour microenvironment, holding promising potential to treat HPV-induced cancer and to prevent cancer recurrence.


Subject(s)
Cancer Vaccines , Dendritic Cells , Oncogene Proteins, Viral , Papillomavirus E7 Proteins , Papillomavirus Infections , Papillomavirus Vaccines , mRNA Vaccines , Animals , Papillomavirus Infections/immunology , Papillomavirus Infections/prevention & control , Papillomavirus E7 Proteins/immunology , Cancer Vaccines/immunology , Oncogene Proteins, Viral/immunology , Oncogene Proteins, Viral/genetics , Papillomavirus Vaccines/immunology , Dendritic Cells/immunology , Humans , Mice , Female , CD8-Positive T-Lymphocytes/immunology , Mice, Inbred C57BL , Nanoparticles , Antigen-Presenting Cells/immunology , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Killer Cells, Natural/immunology , Repressor Proteins/immunology , Repressor Proteins/genetics , Neoplasms/therapy , Neoplasms/immunology , RNA, Messenger/genetics , Cell Line, Tumor , Liposomes
20.
Cancer Sci ; 2024 Aug 18.
Article in English | MEDLINE | ID: mdl-39155589

ABSTRACT

The fundamental role of cells in safeguarding the genome's integrity against DNA double-strand breaks (DSBs) is crucial for maintaining chromatin homeostasis and the overall genomic stability. Aberrant responses to DNA damage, known as DNA damage responses (DDRs), can result in genomic instability and contribute significantly to tumorigenesis. Unraveling the intricate mechanisms underlying DDRs following severe damage holds the key to identify therapeutic targets for cancer. Chromatin lysine acylation, encompassing diverse modifications such as acetylation, lactylation, crotonylation, succinylation, malonylation, glutarylation, propionylation, and butyrylation, has been extensively studied in the context of DDRs and chromatin homeostasis. Here, we delve into the modifying enzymes and the pivotal roles of lysine acylation and their crosstalk in maintaining chromatin homeostasis and genome integrity in response to DDRs. Moreover, we offer a comprehensive perspective and overview of the latest insights, driven primarily by chromatin acylation modification and associated regulators.

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