RESUMO
Aberrant lysine lactylation (Kla) is associated with various diseases which are caused by excessive glycolysis metabolism. However, the regulatory molecules and downstream protein targets of Kla remain largely unclear. Here, we observed a global Kla abundance profile in colorectal cancer (CRC) that negatively correlates with prognosis. Among lactylated proteins detected in CRC, lactylation of eEF1A2K408 resulted in boosted translation elongation and enhanced protein synthesis which contributed to tumorigenesis. By screening eEF1A2 interacting proteins, we identified that KAT8, a lysine acetyltransferase that acted as a pan-Kla writer, was responsible for installing Kla on many protein substrates involving in diverse biological processes. Deletion of KAT8 inhibited CRC tumor growth, especially in a high-lactic tumor microenvironment. Therefore, the KAT8-eEF1A2 Kla axis is utilized to meet increased translational requirements for oncogenic adaptation. As a lactyltransferase, KAT8 may represent a potential therapeutic target for CRC.
Assuntos
Neoplasias Colorretais , Biossíntese de Proteínas , Humanos , Carcinogênese/genética , Transformação Celular Neoplásica , Neoplasias Colorretais/genética , Catálise , Microambiente Tumoral , Histona AcetiltransferasesRESUMO
ADP-ribosylation is a post-translational modification of proteins that plays a key role in various cellular processes, including DNA repair. Recently, significant progress has been made in understanding the mechanism and function of ADP-ribosylation in DNA repair. ADP-ribosylation can regulate the recruitment and activity of DNA repair proteins by facilitating protein-protein interactions and regulating protein conformations. Moreover, ADP-ribosylation can influence additional post-translational modifications (PTMs) of proteins involved in DNA repair, such as ubiquitination, methylation, acetylation, phosphorylation, and SUMOylation. The interaction between ADP-ribosylation and these additional PTMs can fine-tune the activity of DNA repair proteins and ensure the proper execution of the DNA repair process. In addition, PARP inhibitors have been developed as a promising cancer therapeutic strategy by exploiting the dependence of certain cancer types on the PARP-mediated DNA repair pathway. In this paper, we review the progress of ADP-ribosylation in DNA repair, discuss the crosstalk of ADP-ribosylation with additional PTMs in DNA repair, and summarize the progress of PARP inhibitors in cancer therapy.
Assuntos
Neoplasias , Poli(ADP-Ribose) Polimerases , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , ADP-Ribosilação , Reparo do DNA , Processamento de Proteína Pós-Traducional , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas/metabolismoRESUMO
Pseudouridine synthases (PUSs) are responsible for installation of pseudouridine (Ψ) modification in RNA. However, the activity and function of the PUS enzymes remain largely unexplored. Here we focus on human PUS10 and find that it co-expresses with the microprocessor (DROSHA-DGCR8 complex). Depletion of PUS10 results in a marked reduction of the expression level of a large number of mature miRNAs and concomitant accumulation of unprocessed primary microRNAs (pri-miRNAs) in multiple human cells. Mechanistically, PUS10 directly binds to pri-miRNAs and interacts with the microprocessor to promote miRNA biogenesis. Unexpectedly, this process is independent of the catalytic activity of PUS10. Additionally, we develop a sequencing method to profile Ψ in the tRNAome and report PUS10-dependent Ψ sites in tRNA. Collectively, our findings reveal differential functions of PUS10 in nuclear miRNA processing and in cytoplasmic tRNA pseudouridylation.
Assuntos
Hidroliases/metabolismo , MicroRNAs/metabolismo , RNA de Transferência/metabolismo , Linhagem Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Proliferação de Células/fisiologia , Citoplasma/genética , Citoplasma/metabolismo , Regulação da Expressão Gênica , Humanos , Hidroliases/genética , Processamento Pós-Transcricional do RNARESUMO
Mitochondria are essential organelles that provide energy for mammalian cells and participate in multiple functions, such as signal transduction, cellular differentiation, and regulation of apoptosis. Compared with the mitochondria in somatic cells, oocyte mitochondria have an additional level of importance since they are required for germ cell maturation, dysfunction in which can lead to severe inherited disorders. Thus, a systematic proteomic profile of oocyte mitochondria is urgently needed to support the basic and clinical research, but the acquisition of such a profile has been hindered by the rarity of oocyte samples and technical challenges associated with capturing mitochondrial proteins from live oocytes. Here, in this work, using proximity labeling proteomics, we established a mitochondria-specific ascorbate peroxidase (APEX2) reaction in live GV-stage mouse oocytes and identified a total of 158 proteins in oocyte mitochondria. This proteome includes intrinsic mitochondrial structural and functional components involved in processes associated with "cellular respiration", "ATP metabolism", "mitochondrial transport", etc. In addition, mitochondrial proteome capture after oocyte exposure to the antitumor chemotherapeutic cisplatin revealed differential changes in the abundance of several oocyte-specific mitochondrial proteins. Our study provides the first description of a mammalian oocyte mitochondrial proteome of which we are aware, and further illustrates the dynamic shifts in protein abundance associated with chemotherapeutic agents.
Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Oócitos/efeitos dos fármacos , Proteoma/metabolismo , Animais , Ascorbato Peroxidases/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos ICR , Células NIH 3T3 , Proteômica/métodosRESUMO
As the female gamete, meiotic oocytes provide not only half of the genome but also almost all stores for fertilization and early embryonic development. Because de novo mRNA transcription is absent in oocyte meiosis, protein-level regulations, especially the ubiquitin proteasome system, are more crucial. As the largest family of ubiquitin E3 ligases, Skp1-Cullin-F-box complexes recognize their substrates via F-box proteins with substrate-selected specificity. However, the variety of F-box proteins and their unknown substrates hinder our understanding of their functions. In this report, we find that Fbxo30, a new member of F-box proteins, is enriched in mouse oocytes, and its expression level declines substantially after the metaphase of the first meiosis (MI). Notably, depletion of Fbxo30 causes significant chromosome compaction accompanied by chromosome segregation failure and arrest at the MI stage, and this arrest is not caused by over-activation of spindle assembly checkpoint. Using immunoprecipitation and mass spectrometric analysis, we identify stem-loop-binding protein (SLBP) as a novel substrate of Fbxo30. SLBP overexpression caused by Fbxo30 depletion results in a remarkable overload of histone H3 on chromosomes that excessively condenses chromosomes and inhibits chromosome segregation. Our finding uncovers an unidentified pathway-controlling chromosome segregation and cell progress.
Assuntos
Segregação de Cromossomos , Cromossomos de Mamíferos/metabolismo , Proteínas F-Box/genética , Histonas/genética , Meiose , Proteínas Nucleares/genética , Oócitos/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/genética , Animais , Cromossomos de Mamíferos/ultraestrutura , Proteínas F-Box/antagonistas & inibidores , Proteínas F-Box/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Histonas/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Proteínas Nucleares/metabolismo , Oócitos/ultraestrutura , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA , Transdução de Sinais , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismoRESUMO
Endogenous retroviruses (ERVs) are transcriptionally active in cleavage stage embryos, yet their functions are unknown. ERV sequences are present in the majority of long intergenic noncoding RNAs (lincRNAs) in mouse and humans, playing key roles in many cellular processes and diseases. Here, we identify LincGET as a nuclear lincRNA that is GLN-, MERVL-, and ERVK-associated and essential for mouse embryonic development beyond the two-cell stage. LincGET is expressed in late two- to four-cell mouse embryos. Its depletion leads to developmental arrest at the late G2 phase of the two-cell stage and to MAPK signaling pathway inhibition. LincGET forms an RNA-protein complex with hnRNP U, FUBP1, and ILF2, promoting the cis-regulatory activity of long terminal repeats (LTRs) in GLN, MERVL, and ERVK (GLKLTRs), and inhibiting RNA alternative splicing, partially by downregulating hnRNP U, FUBP1, and ILF2 protein levels. Hnrnpu or Ilf2 mRNA injection at the pronuclear stage also decreases the preimplantation developmental rate, and Fubp1 mRNA injection at the pronuclear stage causes a block at the two-cell stage. Thus, as the first functional ERV-associated lincRNA, LincGET provides clues for ERV functions in cleavage stage embryonic development.
Assuntos
Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Clivagem do RNA , RNA Longo não Codificante/genética , Processamento Alternativo , Animais , DNA Helicases/metabolismo , Retrovirus Endógenos/genética , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Regulação da Expressão Gênica no Desenvolvimento , Ribonucleoproteínas Nucleares Heterogêneas Grupo U/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Modelos Biológicos , Proteína do Fator Nuclear 45/metabolismo , Ligação Proteica , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
Differentiated cells can be reprogrammed by transcription factors, and these factors that are responsible for successful reprogramming need to be further identified. Here, we show that the neuronal repressor RE1-silencing transcription factor (REST) is rich in porcine oocytes and requires for nuclear transfer (NT)-mediated reprogramming through inhibiting TGFß signaling pathway. REST was dramatically degraded after oocyte activation, but the residual REST was incorporated into the transferred donor nuclei during reprogramming in NT embryos. Inhibition of REST function in oocytes compromised the development of NT embryos but not that of IVF and PA embryos. Bioinformation analysis of putative targets of REST indicated that REST might function on reprogramming in NT embryos by inhibiting TGFß pathway. Further results showed that the developmental failure of REST-inhibited NT embryos could be rescued by treatment of SB431542, an inhibitor of TGFß pathway. Thus, REST is a newly discovered transcription factor that is required for NT-mediated nuclear reprogramming.
Assuntos
Blastocisto/metabolismo , Núcleo Celular/genética , Reprogramação Celular , Embrião de Mamíferos/metabolismo , Oócitos/metabolismo , Proteínas Repressoras/metabolismo , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais , Blastocisto/citologia , Diferenciação Celular , Células Cultivadas , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Feminino , Técnicas de Transferência Nuclear , Oócitos/citologia , Proteínas Repressoras/genética , Suínos , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismoRESUMO
Aberrant epigenetic reprogramming is the main obstacle to the development of somatic cell nuclear transfer (SCNT) embryos and the generation of induced pluripotent stem (iPS) cells, which results in the low reprogramming efficiencies of SCNT and iPS. Histone H3 lysine 27 trimethylation (H3K27me3), as a repressive epigenetic mark, plays important roles in mammalian development and iPS induction. However, the reprogramming of H3K27me3 in pig remains elusive. In this study, we showed that H3K27me3 levels in porcine early cloned embryos were higher than that in IVF embryos. Then GSK126 and GSK-J4, two small molecule inhibitors of H3K27me3 methylase (EZH2) and demethylases (UTX/JMJD3), were used to regulate the H3K27me3 level. The results showed that H3K27me3 level was reduced in cloned embryos after treatment of PEF with 0.75âµM GSK126 for 48âh, incubation of one-cell reconstructed oocytes with 0.1âµM GSK126 and injection of antibody for EZH2 into oocyte. Meanwhile, the development of the cloned embryos was significantly improved after these treatments. On the contrary, GSK-J4 treatment increased the H3K27me3 level in cloned embryos and decreased the cloned embryonic development. Furthermore, iPS efficiency was both increased after reducing the H3K27me3 level in donor cells and in early reprogramming phase. In summary, our results suggest that H3K27me3 acts as an epigenetic barrier in SCNT and iPS reprogramming, and reduction of H3K27me3 level in donor cells and in early reprogramming phase can enhance both porcine SCNT and iPS efficiency.
Assuntos
Reprogramação Celular/genética , Epigênese Genética/fisiologia , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Sus scrofa/embriologia , Animais , Benzazepinas/farmacologia , Clonagem de Organismos , Embrião de Mamíferos/química , Desenvolvimento Embrionário/efeitos dos fármacos , Fertilização in vitro/veterinária , Histona Desmetilases/antagonistas & inibidores , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histonas/análise , Indóis/farmacologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Técnicas de Transferência Nuclear/veterinária , Partenogênese , Piridonas/farmacologia , Pirimidinas/farmacologiaRESUMO
Nuclear reprogramming of somatic cells can be induced by oocyte factors. Despite numerous attempts, the factors responsible for successful nuclear reprogramming remain elusive. In the present study, we found that porcine oocytes with the first polar body collected at 42 h of in vitro maturation had a stronger ability to support early development of cloned embryos than porcine oocytes with the first polar body collected at 33 h of in vitro maturation. To explore the key reprogramming factors responsible for the difference, we compared proteome signatures of the two groups of oocytes. 18 differentially expressed proteins between these two groups of oocytes were discovered by mass spectrometry (MS). Among these proteins, we especially focused on vimentin (VIM). A certain amount of VIM protein was stored in oocytes and accumulated during oocyte maturation, and maternal VIM was specifically incorporated into transferred somatic nuclei during nuclear reprogramming. When maternal VIM function was inhibited by anti-VIM antibody, the rate of cloned embryos developing to blastocysts was significantly lower than that of IgG antibody-injected embryos and non-injected embryos (12.24 versus 22.57 and 21.10%; p < 0.05), but the development of in vitro fertilization and parthenogenetic activation embryos was not affected. Furthermore, we found that DNA double strand breaks dramatically increased and that the p53 pathway was activated in cloned embryos when VIM function was inhibited. This study demonstrates that maternal VIM, as a genomic protector, is crucial for nuclear reprogramming in porcine cloned embryos.
Assuntos
Reprogramação Celular , Clonagem de Organismos , Oócitos/fisiologia , Suínos/embriologia , Vimentina/metabolismo , Animais , Blastocisto/metabolismo , Blastocisto/fisiologia , Desenvolvimento Embrionário , Feminino , Técnicas de Transferência Nuclear , Oócitos/metabolismo , Corpos Polares/metabolismo , Corpos Polares/fisiologia , Suínos/genética , Suínos/metabolismo , Vimentina/antagonistas & inibidoresRESUMO
Mammalian oocytes possess factors to support fertilization and embryonic development, but knowledge on these oocyte-specific factors is limited. In the current study, we demonstrated that porcine oocytes with the first polar body collected at 33âh of in vitro maturation sustain IVF with higher sperm decondensation and pronuclear formation rates and support in vitro development with higher cleavage and blastocyst rates, compared with those collected at 42âh (P<0.05). Proteomic analysis performed to clarify the mechanisms underlying the differences in developmental competence between oocytes collected at 33 and 42âh led to the identification of 18 differentially expressed proteins, among which protein disulfide isomerase associated 3 (PDIA3) was selected for further study. Inhibition of maternal PDIA3 via antibody injection disrupted sperm decondensation; conversely, overexpression of PDIA3 in oocytes improved sperm decondensation. In addition, sperm decondensation failure in PDIA3 antibody-injected oocytes was rescued by dithiothreitol, a commonly used disulfide bond reducer. Our results collectively report that maternal PDIA3 plays a crucial role in sperm decondensation by reducing protamine disulfide bonds in porcine oocytes, supporting its utility as a potential tool for oocyte selection in assisted reproduction techniques.
Assuntos
Oócitos/enzimologia , Comunicação Parácrina , Isomerases de Dissulfetos de Proteínas/metabolismo , Interações Espermatozoide-Óvulo , Espermatozoides/enzimologia , Animais , Células Cultivadas , Feminino , Fertilização in vitro , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Técnicas de Maturação in Vitro de Oócitos , Masculino , Isomerases de Dissulfetos de Proteínas/genética , Proteômica/métodos , RNA Mensageiro/metabolismo , Transdução de Sinais , Injeções de Esperma Intracitoplásmicas , Suínos , Fatores de Tempo , TransfecçãoRESUMO
Biosensors, devices capable of detecting biomolecules or bioactive substances, have recently become one of the important tools in the fields of bioanalysis and medical diagnostics. A biosensor is an analytical system composed of biosensitive elements and signal-processing elements used to detect various biological and chemical substances. Biomimetic elements are key to biosensor technology and are the components in a sensor that are responsible for identifying the target analyte. The construction methods and working principles of biosensors based on synthetic biomimetic elements, such as DNAzyme, molecular imprinted polymers and aptamers, and their updated applications in biomedical analysis are summarised. Finally, the technical bottlenecks and future development prospects for biomedical analysis are summarised and discussed.
RESUMO
In this study, we have designed an electrochemical biosensor based on topological material Bi2Se3 for the sensitive detection of SARS-CoV-2 in the COVID-19 pandemic. Flake-shaped Bi2Se3 was obtained directly from high-quality single crystals using mechanical exfoliation, and the single-stranded DNA was immobilized onto it. Under optimal conditions, the peak current of the differential pulse voltammetry method exhibited a linear relationship with the logarithm of the concentration of target-complementary-stranded DNA, ranging from 1.0 × 10-15 to 1.0 × 10-11 M, with a detection limit of 3.46 × 10-16 M. The topological material Bi2Se3, with Dirac surface states, enhanced the signal-to-interference plus noise ratio of the electrochemical measurements, thereby improving the sensitivity of the sensor. Furthermore, the electrochemical sensor demonstrated excellent specificity in recognizing RNA. It can detect complementary RNA by amplifying and transcribing the initial DNA template, with an initial DNA template concentration ranging from 1.0 × 10-18 to 1.0 × 10-15 M. Furthermore, the sensor also effectively distinguished negative and positive results by detecting splitting-synthetic SARS-CoV-2 pseudovirus with a concentration of 1 copy/µL input. Our work underscores the immense potential of the electrochemical sensing platform based on the topological material Bi2Se3 in the detection of pathogens during the rapid spread of acute infectious diseases.
Assuntos
Técnicas Biossensoriais , Bismuto , COVID-19 , Técnicas Eletroquímicas , Limite de Detecção , SARS-CoV-2 , Técnicas Biossensoriais/métodos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , COVID-19/diagnóstico , COVID-19/virologia , Bismuto/química , Técnicas Eletroquímicas/métodos , Humanos , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , RNA Viral/genética , RNA Viral/análise , Compostos de Selênio/químicaRESUMO
BACKGROUND: Poly(ADP-ribose) polymerase (PARP) inhibitors have emerged as promising chemotherapeutic drugs primarily against BRCA1/2-associated tumours, known as synthetic lethality. However, recent clinical trials reported patients' survival benefits from PARP inhibitor treatments, irrelevant to homologous recombination deficiency. Therefore, revealing the therapeutic mechanism of PARP inhibitors beyond DNA damage repair is urgently needed, which can facilitate precision medicine. METHODS: A CRISPR-based knock-in technology was used to establish stable BRCA1 mutant cancer cells. The effects of PARP inhibitors on BRCA1 mutant cancer cells were evaluated by biochemical and cell biological experiments. Finally, we validated its in vivo effects in xenograft and patient-derived xenograft (PDX) tumour mice. FINDINGS: In this study, we uncovered that the majority of clinical BRCA1 mutations in breast cancers were in and near the middle of the gene, rather than in essential regions for DNA damage repair. Representative mutations such as R1085I and E1222Q caused transient extra spindle poles during mitosis in cancer cells. PAR, which is synthesized by PARP2 but not PARP1 at mitotic centrosomes, clustered these transient extra poles, independent of DNA damage response. Common PARP inhibitors could effectively suppress PARP2-synthesized PAR and induce cell senescence by abrogating the correction of mitotic extra-pole error. INTERPRETATION: Our findings uncover an alternative mechanism by which PARP inhibitors efficiently suppress tumours, thereby pointing to a potential new therapeutic strategy for centrosome error-related tumours. FUNDING: Funded by National Natural Science Foundation of China (NSFC) (T2225006, 82272948, 82103106), Beijing Municipal Natural Science Foundation (Key program Z220011), and the National Clinical Key Specialty Construction Program, P. R. China (2023).
Assuntos
Proteína BRCA1 , Senescência Celular , Centrossomo , Dano ao DNA , Inibidores de Poli(ADP-Ribose) Polimerases , Ensaios Antitumorais Modelo de Xenoenxerto , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Humanos , Animais , Centrossomo/metabolismo , Centrossomo/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Camundongos , Proteína BRCA1/genética , Linhagem Celular Tumoral , Feminino , Mutação , Reparo do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genéticaRESUMO
Interferon-γ (IFN-γ) is one of the crucial inflammatory cytokines as an early indicator of multiple diseases. A fast, simple, sensitive and reliable IFN-γ detection method is valuable for early diagnosis and monitoring of treatment. In this work, we creatively developed an electrochemical aptasensor based on the topological material Bi2Se3 for sensitive IFN-γ quantification. The high-quality Bi2Se3 sheet was directly exfoliated from a single crystal, which immobilized the synthesized IFN-γ aptamer. Under optimal conditions, the electrochemical signal revealed a wide linear relation along with the logarithmic concentration of IFN-γ from 1.0 pg mL-1 to 100.0 ng mL-1, with the limit of detection as low as 0.5 pg mL-1. The topological material Bi2Se3 with Dirac surface states improved the electrochemical signal/noise ratio and thus the sensitivity of the sensors. Furthermore, this electrochemical aptasensor exhibited excellent specificity and stability, which could be attributed to the large-scale smooth surface of the Bi2Se3 sheet with few defects decreasing the non-specific absorption. The developed biosensor has the same good performance as the ELISA method for detecting the real serum samples. Our work demonstrates that the developed electrochemical aptasensors based on topological materials have great potential in the field of clinical determination.
Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Interferon gama , Bismuto/química , Selênio/químicaRESUMO
Telomeres are repeated GC rich sequences at the end of chromosomes, and shorten with each cell division due to DNA end replication problem. Previously, reprogrammed somatic cells of cloned animals display variable telomere elongation. However, it was reported that the cloned animals including Dolly do not reset telomeres and show premature aging. In this study, we investigated telomere function in cloned or transgenic cloned pigs, including the cloned Northeast Min pigs, eGFP, Mx, and PGC1α transgenic cloned pigs, and found that the telomere lengths of cloned pigs were significantly shorter than the nuclear donor adult fibroblasts and age-matched noncloned pigs (P<0.05), indicating that nuclear reprogramming did not restore cellular age of donor cells after somatic cell nuclear transfer (SCNT). Trichostatin A (TSA), an inhibitor of histone deacetylase, has proven to enhance the efficiency of nuclear reprogramming in several species. In order to test whether TSA also can effectively enhance reprogramming of telomeres, TSA (40 nmol/L) was used to treat porcine cloned embryos at 1-cell stage for 24 h. Consistent with previous reports, the developmental rate of SCNT embryos to the blastocyst stage was significantly increased compared with those of the control group (16.35% vs. 27.09%, 21.60% vs. 34.90%, P<0.05). Notably, the telomere length of cloned porcine blastocysts was also significantly elongated (P<0.05). Although TSA did not improve the cloning efficiency (1.3% vs. 1.7%, TSA vs. control), the telomere lengths of cloned pig-lets were significantly longer compared with those of the control group and the donor fibroblasts (P<0.05). In conclusion, telomeres have not been effectively restored by SCNT in pigs but TSA can effectively lengthen the telomere lengths of cloned pigs.
Assuntos
Ácidos Hidroxâmicos/farmacologia , Suínos/genética , Homeostase do Telômero/efeitos dos fármacos , Telômero/genética , Animais , Animais Geneticamente Modificados , Blastocisto/citologia , Blastocisto/efeitos dos fármacos , Blastocisto/metabolismo , Clonagem de Organismos , Suínos/embriologia , Suínos/metabolismo , Telômero/metabolismoRESUMO
The repair of DNA damage is a complex process, which helps to maintain genome fidelity, and the ability of cancer cells to repair therapeutically DNA damage induced by clinical treatments will affect the therapeutic efficacy. In the past decade, great success has been achieved by targeting the DNA repair network in tumors. Recent studies suggest that DNA damage impacts cellular innate and adaptive immune responses through nucleic acid-sensing pathways, which play essential roles in the efficacy of DNA repair targeted therapy. In this review, we summarize the current understanding of the molecular mechanism of innate immune response triggered by DNA damage through nucleic acid-sensing pathways, including DNA sensing via the cyclic GMP-AMP synthase (cGAS), Toll-like receptor 9 (TLR9), absent in melanoma 2 (AIM2), DNA-dependent protein kinase (DNA-PK), and Mre11-Rad50-Nbs1 complex (MRN) complex, and RNA sensing via the TLR3/7/8 and retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs). Furthermore, we will focus on the recent developments in the impacts of nucleic acid-sensing pathways on the DNA damage response (DDR). Elucidating the DDR-immune response interplay will be critical to harness immunomodulatory effects to improve the efficacy of antitumor immunity therapeutic strategies and build future therapeutic approaches.
RESUMO
Breast cancer type 1 susceptibility protein (BRCA1) is essential for homologous recombination repair of DNA double-strand breaks. Loss of BRCA1 is lethal to embryos due to extreme genomic instability and the activation of p53-dependent apoptosis. However, the apoptosis is resisted in BRCA1-deficient cancer cells even though their p53 is proficient. In this study, by analysis of transcriptome data of ovarian cancer patients bearing BRCA1 defects in TCGA database, we found that cAMP signaling pathway was significantly activated. Experimentally, we found that BRCA1 deficiency caused an increased expression of ADRB1, a transmembrane receptor that can promote the generation of cAMP. The elevated cAMP not only inhibited DNA damage-induced apoptosis through abrogating p53 accumulation, but also suppressed the proliferation of cytotoxic T lymphocytes by enhancing the expression of immunosuppressive factors DKK1. Inhibition of ADRB1 effectively killed cancer cells by abolishing the apoptotic resistance. These findings uncover a novel mechanism of apoptotic resistance in BRCA1-deficient ovarian cancer cells and point to a potentially new strategy for treating BRCA1-mutated tumors.
RESUMO
Human IgG is one of the most important immunoglobulins in the human body. The present study described the fabrication of four kinds of layer-by-layer structures of copper metal-organic frameworks (Cu-MOFs) on the working electrode by electrodeposition, which were then applied as an electrochemical sensor for the sensitive determination of IgG in serum. First, MOFs synthesized using different deposition potentials are expected to have varied morphology and properties. Herein, four copper MOFs (Cu-MOFs) were electrosynthesized by a simple and direct reduction approach. The as-synthesized Cu-MOFs exhibit varied morphology and electrocatalytic behavior. Then, IgG was employed as a template in the electropolymerization of pyrrole-imprinted films on the surface of glassy carbon electrodes. Finally, the template protein was removed to form a molecularly imprinted film with the capability to qualitatively and quantitatively signaling of IgG. Under optimized conditions, the sensor for IgG exhibits a wide detection range of 0.01-10 ng mL-1 with a limit of detection (LOD) of 3 pg mL-1 (S/N = 3). Besides, other parameters including the selectivity, reproducibility (RSD 3.6%), and recovery rate (95.2-102.0%) are all satisfactory. The practicability of the sensor was verified by detecting IgG in human serum samples, which indicated that the sensor was suitable for potential clinical applications.
Assuntos
Estruturas Metalorgânicas , Impressão Molecular , Cobre , Técnicas Eletroquímicas , Eletrodos , Humanos , Imunoglobulina G , Limite de Detecção , Estruturas Metalorgânicas/química , Reprodutibilidade dos TestesRESUMO
Recent work has made it clear that pericentriolar material (PCM), the matrix of proteins surrounding centrioles, contributes to most functions of centrosomes. Given the occurrence of centrosome amplification in most solid tumors and the unconventional survival of these tumor cells, it is tempting to hypothesize that gel-like mitotic PCM would cluster extra centrosomes to defend against mitotic errors and increase tumor cell survival. However, because PCM lacks an encompassing membrane, is highly dynamic, and is physically connected to centrioles, few methods can decode the components of this microscale matrix. In this study, we took advantage of differential labeling between two sets of APEX2-centrosome reactions to design a strategy for acquiring the PCM proteome in living undisturbed cells without synchronization treatment, which identified 392 PCM proteins. Localization of ubiquitination promotion proteins away from PCM was a predominant mechanism to maintain the large size of PCM for centrosome clustering during mitosis in cancer cells. Depletion of PCM gene kinesin family member 20A (KIF20A) caused centrosome clustering failure and apoptosis in cancer cells in vitro and in vivo. Thus, our study suggests a strategy for targeting a wide range of tumors exhibiting centrosome amplification and provides a proteomic resource for future mining of PCM proteins. SIGNIFICANCE: This study identifies the proteome of pericentriolar material and reveals therapeutic vulnerabilities in tumors bearing centrosome amplification.
Assuntos
Proteoma , Proteômica , Centríolos/metabolismo , Centrossomo/metabolismo , Humanos , Mitose , Proteoma/metabolismoRESUMO
This study aimed to examine the effects of adding growth hormone (GH) into the in vitro maturation (IVM) culture medium of mouse oocytes on pregnancy outcomes. Cumulus-oocyte complexes (COCs) were cultured in a medium with (GH group, 100 ng/mL) or without (Con group) GH. Thereafter, chromosome morphology, spindle morphology, and mitochondrial function were examined. Embryo development and blastocyst quality after in vitro fertilization were evaluated. After the embryo transfer, the implantation sites and pregnancy outcomes were evaluated. The oocyte maturation rate of the GH group (81.8 ± 9.6%) was compared to that of the Con group (81.3 ± 6.9%, P = 0.928). The proportion of morphologically abnormal spindles in GH-treated oocytes (7.1 ± 0.9%) was significantly lower than control oocytes (13.7 ± 1.3%, P = 0.032), whereas the proportion of morphologically abnormal chromosomes and mitochondrial distribution was similar between the groups. The mitochondrial membrane potential (P < 0.001) and ATP concentration (P < 0.001) in GH-exposed oocytes were higher than those in control oocytes. After fertilization, the blastocyst rate in the GH group (33.8 ± 13.2%) was significantly higher than the Con group (16.2 ± 2.0%, P = 0.003). In addition, inner cell mass (ICM) number (13.91 ± 3.48 vs. 7.00 ± 1.91, P < 0.001), total cell number (47.45 ± 8.39 vs. 37.71 ± 4.15, P = 0.007), and the ratio of ICM/total cell number (29.9 ± 8.2% vs. 18.6 ± 5.0%, P = 0.002) of blastocyst were all higher in GH group. The implantation rate (71.2 ± 1.9% vs. 39.4 ± 16.4%, P < 0.001) and litter size (8.50 ± 3.99 vs. 3.00 ± 1.22, P = 0.018) were significantly higher in the GH group. Although addition of GH into IVM culture medium does not improve oocyte maturation rate, it improves oocyte and embryo quality, which leads to better embryo development and pregnancy outcomes.