Objective To investigate the effect of basic helix-loop-helix family member E40 (BHLHE40) on the invasion and migration of osteosarcoma (OS) cells, and to explore the role of the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway in the biological behavior of OS mediated by BHLHE40, providing a scientific basis for targeted therapy of OS. Methods On the basis of clinical OS samples and OS cell lines, the expression differences of BHLHE40 between OS and adjacent tissues, as well as those between OS cells and normal osteoblast cell lines, were analyzed. BHLHE40 knockdown OS cells were obtained through shRNA transfection. The effects of BHLHE40 on OS cell proliferation, migration, and invasion were examined using CCK-8, EdU staining, wound healing, and Transwell assays. The involvement of the PI3K/AKT signaling pathway was assessed by Western blotting. Further validation was conducted in vivo experiments. Results The expression of BHLHE40 was significantly higher in OS tissues compared to adjacent tissues. In OS cell lines, BHLHE40 protein expression levels were increased compared to normal osteoblasts, and the cell line with the highest BHLHE40 expression was selected for subsequent knockdown experiments. Compared with the knockdown control group, the BHLHE40 knockdown group exhibited reduced cell viability, EdU-positive cell count, colony number, cell migration, and invasion abilities, along with downregulation of phosphorylated PI3K(p-PI3K)/PI3K and p-AKT/AKT protein expression. The aforementioned functions of BHLHE40 were also reproduced in in vivo experiments. Conclusion BHLHE40 is highly expressed in OS tissues, and its knockdown can significantly inhibit OS cell proliferation, migration, and invasion, while reducing PI3K/AKT signaling pathway activity. This suggests that BHLHE40 could serve as a novel therapeutic target for OS.
Osteosarcoma/metabolism* ; Humans ; Proto-Oncogene Proteins c-akt/genetics* ; Cell Proliferation/genetics* ; Cell Movement/genetics* ; Signal Transduction/genetics* ; Phosphatidylinositol 3-Kinases/genetics* ; Cell Line, Tumor ; Animals ; Neoplasm Invasiveness ; Basic Helix-Loop-Helix Transcription Factors/metabolism* ; Bone Neoplasms/metabolism* ; Mice ; Gene Knockdown Techniques ; Male ; Female ; Mice, Nude

Objective To explore the effect of the knockdown of transmembrane 9 superfamily protein member 2 (TM9SF2) on the replication of vesicular stomatitis virus (VSV), and investigate its role in the mechanism of antiviral innate immunity. Methods Small interfering RNA (siRNA) was used to knock down the TM9SF2 gene in human non-small cell lung cancer A549 cells. The CCK-8 method was used to assess cell proliferation. A VSV-green fluorescent protein (VSV-GFP) infected cell model was established. The plaque assay was used to measure the viral titer in the supernatant. RT-qPCR and Western blotting were employed to quantify the mRNA and protein levels of VSV genome replication in A549 cells following VSV infection, as well as the expression of interferon β (IFN-β) mRNA and interferon regulatory factor 3 (IRF3) protein phosphorylation following polyinosinic-polycytidylic acid (poly(I:C)) stimulation. Results Compared to the negative control, the knockdown of TM9SF2 exhibited a significant effect, with no observed impact on A549 cell proliferation. The VSV-GFP infected A549 cell model was successfully established. After viral stimulation, fluorescence intensity was reduced following TM9SF2 knockdown, and the mRNA and protein levels of VSV were significantly downregulated. The viral titer of VSV was decreased. After poly(I:C) stimulation, TM9SF2 knockdown significantly upregulated the mRNA level of IFN-β and the phosphorylation level of IRF3 protein. Conclusion The knockdown of TM9SF2 inhibits the replication of vesicular stomatitis virus, and positively regulates the type I interferon signaling pathway, thus enhancing the host's antiviral innate immune response.
Humans ; Virus Replication/genetics* ; Signal Transduction ; Membrane Proteins/metabolism* ; A549 Cells ; Vesiculovirus/physiology* ; Interferon-beta/metabolism* ; Interferon Regulatory Factor-3/genetics* ; Interferon Type I/metabolism* ; Vesicular Stomatitis/immunology* ; Gene Knockdown Techniques ; Vesicular stomatitis Indiana virus/physiology* ; RNA, Small Interfering/genetics*

OBJECTIVE: To initially investigate the function of neuronal pentraxin 1 (NPTX1) gene on osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). METHODS: hBMSCs were induced to undergo osteogenic differentiation, and then RNA was collected at different time points, namely 0, 3, 7, 10 and 14 d. The mRNA expression levels of key genes related with osteogenic differentiation, including runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN), and NPTX1, were detected on the basis of quantitative real-time polymerase chain reaction (qPCR) technology. In order to establish a stable NPTX1-knockdown hBMSCs cell line, NPTX1 shRNA lentivirus was constructed and used to infect hBMSCs. ALP staining, alizarin red (AR) staining, and qPCR were employed to assess the impact of NPTX1-knockdown on the osteogenic differentiation ability of hBMSCs. RESULTS: The results showed that during the osteogenic differentiation of hBMSCs in vitro, the mRNA expression levels of osteogenic genes RUNX2, ALP and OCN significantly increased compared with 0 d, while NPTX1 expression decreased markedly (P < 0.01) as the osteogenic induction period exten-ded. At 72 h post-infection with lentivirus, the result of qPCR indicated that the knockdown efficiency of NPTX1 was over 60%. After knocking down NPTX1 in hBMSCs, RNA was extracted from both the NPTX1-knockdown group (sh NPTX1 group) and the control group (shNC group) cultured in regular proliferation medium. The results of qPCR showed that the expression levels of osteogenic-related genes RUNX2 and osterix (OSX) were significantly higher in the sh NPTX1 group compared with the shNC group (P < 0.01). ALP staining revealed a significantly deeper coloration in the sh NPTX1 group than in the shNC group at the end of 7 d of osteogenic induction. AR staining demonstrated a marked increase in mineralized nodules in the sh NPTX1 group compared with the shNC group at the end of 14 d of osteogenic induction. CONCLUSION NPTX1 exerts a modulatory role in the osteogenic differentiation of hBMSCs, and its knockdown has been found to enhance the osteogenic differentiation of hBMSCs. This finding implies that NPTX1 could potentially serve as a therapeutic target for the treatment of osteogenic abnormalities, including osteoporosis.
Humans ; Mesenchymal Stem Cells/cytology* ; Osteogenesis/genetics* ; Cell Differentiation/genetics* ; Nerve Tissue Proteins/genetics* ; Cells, Cultured ; C-Reactive Protein/genetics* ; RNA, Small Interfering/genetics* ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Bone Marrow Cells/cytology* ; Gene Knockdown Techniques ; Osteocalcin/metabolism* ; Alkaline Phosphatase/metabolism* ; RNA, Messenger/metabolism*

OBJECTIVE: To explore the changes of CKLF-like MARVEL transmembrane domain-containing 6 (CMTM6) and programmed death-ligand 1 (PD-L1) expression in gastric mucosal epithelial cells after Helicobacter pylori infection and the regulation of CMTM6 on PD-L1, and to analyze the mRNA expression differences before and after CMTM6 gene knock-out in helicobacter pylori infected gastric epithelial cells by microarray analysis. METHODS: The standard Helicobacter pylori strain ATCC 26695 was co-cultured with human gastric epithelial cell GES-1 for 6, 24 and 48 hours, and the mRNA and protein levels of CMTM6 and PD-L1 were detected by real-time quantitative PCR and Western blot. Using CRISPR/Cas9 to construct CMTM6 gene knockout plasmid and knockout CMTM6 gene of GES-1 cells. Helicobacter pylori was co-cultured with CMTM6 gene knockout and wild type GES-1 cells for 48 hours to detect PD-L1 transcription and protein level changes, and CMTM6 gene knockout GES-1 cells were treated with the proteasome inhibitor MG-132 to detect the changes in PD-L1 protein levels. Agilent Human ceRNA Microarray 2019 was used to detect the differentially expressed genes in CMTM6 gene knockout and wild-type GES-1 cells co-cultured with Hp for 48 hours, and the signal pathway of differentially expressed genes enrichment was analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) database. RESULTS: The mRNA and protein levels of CMTM6 and PD-L1 in GES-1 cells were significantly up-regulated after Helicobacter pylori infection, and CMTM6 mRNA was most significantly up-regulated 48 hours after infection. After CMTM6 gene knockout, the CD274 gene transcription level of Helicobacter pylori infected GES-1 cells did not change significantly, but PD-L1 protein level was significantly down-regulated, and the PD-L1 level increased after the application of proteasome inhibitor MG-132. After CMTM6 gene knockout, 67 genes had more than two times of differential expression. The transcription levels of TMEM68, FERMT3, GPR142, ATP6V1FNB, NOV, UBE2S and other genes were significantly down-regulated. The transcription levels of PCDHGA6, CAMKMT, PDIA2, NTRK3, SPOCK1 and other genes were significantly up-regulated. After CMTM6 gene knockout, ubiquitin-conjugating enzyme E2S (UBE2S) gene expression was significantly down-regulated, which might affect protein ubiquitination degradation. After CMTM6 gene knockout, adrenoceptor alpha 1B (ADRA1B), cholinergic receptor muscarinic 1 (M1), CHRM1, platelet activating factor receptor (PTAFR) gene expression was significantly up-regulated. CONCLUSION Helicobacter pylori infection up-regulates the expression level of CMTM6 in gastric mucosa cells, and CMTM6 can stabilize PD-L1 and maintain the protein level of PD-L1. CMTM6 gene knockout may affect biological behaviors such as protein ubiquitination and cell surface receptor expression.
Humans ; MARVEL Domain-Containing Proteins/metabolism* ; Helicobacter pylori/physiology* ; B7-H1 Antigen/genetics* ; Helicobacter Infections/metabolism* ; Epithelial Cells/metabolism* ; Gastric Mucosa/metabolism* ; Chemokines/metabolism* ; Cell Line ; Gene Knockout Techniques ; Myelin Proteins

OBJECTIVES: The purinergic receptor P2X2 (P2RX2) encodes an ATP-gated ion channel permeable to Na⁺, K⁺, and especially Ca²⁺. Loss-of-function mutations in P2RX2 are known to cause autosomal dominant nonsyndromic deafness 41 (DFNA41), which manifests as high-frequency hearing loss, accelerated presbycusis, and increased susceptibility to noise-induced damage. Zebrafish, owing to their small size, rapid development, high fecundity, transparent embryos, and high gene conservation with humans, provide an ideal model for studying human diseases and developmental mechanisms. This study aims to generate a p2rx2 knockout zebrafish model using CRISPR/Cas9 gene editing system to investigate the effect of p2rx2 deficiency on the auditory system, providing a basis for understanding P2RX2-related hearing loss and developing gene therapy strategies. METHODS: Two CRISPR targets (sgRNA1 and sgRNA2) spaced 47 bp apart were designed within the zebrafish p2rx2 gene. Synthesized sgRNAs and Cas9 protein were microinjected into single-cell stage Tübingen (TU)-strain zebrafish embryos. PCR and gel electrophoresis verified editing efficiency at 36 hours post-fertilization (hpf). Surviving embryos were raised to adulthood (F0), tail-clipped, genotyped, and screened for positive mosaics. F1 heterozygotes were generated by outcrossing, and F2 homozygous mutants were obtained by intercrossing. Polymerase chain reaction (PCR) combined with sequencing verified mutation type and heritability. At 5 days post-fertilization (dpf), YO-PRO-1 staining was used to examine hair cell morphology and count in lateral line neuromasts and the otolith region. Auditory evoked potential (AEP) thresholds at 600, 800, 1 000, and 2 000 Hz were measured in nine 4-month-old wild type and mutant zebrafish per group. RESULTS: A stable p2rx2 knockout zebrafish line was successfully established. Sequencing revealed a 66 bp insertion at the first target site introducing a premature stop codon (TAA), leading to early termination of protein translation and loss of function. Embryos developed normally with no gross malformations. At 5 dpf, mutants exhibited significantly reduced hair cell density in the otolith region compared with wild type, although lateral line neuromasts were unaffected. AEP testing showed significantly elevated auditory thresholds at all 4 frequencies in homozygous mutants compared with wild type (all P<0.001), indicating reduced hearing sensitivity. CONCLUSIONS We successfully generated a p2rx2 loss-of-function zebrafish model using CRISPR/Cas9 technology. p2rx2 deficiency caused hair cell defects in the otolith region and increased auditory thresholds across frequencies, indicating its key role in maintaining zebrafish auditory hair cell function and hearing perception. The phenotype's restriction to the otolith region suggests tissue-specific roles of p2rx2 in sensory organs. This model provides a valuable tool for elucidating the molecular mechanisms of P2RX2-related hearing loss and for screening otoprotective drugs and developing gene therapies.
Animals ; Zebrafish/genetics* ; Receptors, Purinergic P2X2/deficiency* ; CRISPR-Cas Systems/genetics* ; Gene Knockout Techniques ; Phenotype ; Zebrafish Proteins/genetics* ; Disease Models, Animal

OBJECTIVES: To study the effect of CDC20 knockdown on proliferation, migration and invasion of cervical cancer cells and its underlying mechanism. METHODS: CDC20 expression in cervical cancer tissues was analyzed using the TCGA database, and the protein expressions of CDC20 and β-Catenin in clinical specimens of cervical cancer and adjacent tissues were detected using immunohistochemistry. A dual target sgRNA2&7 sequence for CDC20 gene was designed for CDC20 gene knockdown in cervical cancer C33A cells using CRISPR/Cas9 technology, and CDC20 mRNA and protein expression levels in the transfected cells were detected using qRT-PCR and Western blotting. The changes in proliferation, cell cycle, apoptosis, migration and invasiveness of the transfected cells were evaluated using colony-forming assay, fluorescence activated cell sorting (FACS) and Transwell assay. In the animal experiment, naïve C33A cells and the cells with CDC20 knockdown were injected subcutaneously into the left and right axillae of nude mice (n=5) to observe tumor growth. The expressions of CDC20 and β-Catenin proteins in transfected cells and the xenograft were analyzed using Western blotting, and their interaction was confirmed by co-immunoprecipitation (CoIP) and immunofluorescence co-localization assays. RESULTS: Cervical cancer tissues expressed significantly higher CDC20 and β‑Catenin levels than the adjacent tissues. C33A cells with CDC20 knockdown showed reduced proliferation, increased apoptosis, and lowered migration and invasion abilities. CDC20 knockdown significantly suppressed the growth of C33A cell xenograft in nude mice, and the tumor-bearing mice did not exhibit obvious body mass changes. CDC20 and β-Catenin levels were both significantly lowered in C33A cells with CDC20 knockdown. Co-immunoprecipitation and co-localization assays confirmed the interaction between CDC20 and β‑Catenin. CONCLUSIONS CDC20 is highly expressed in cervical cancer tissues, and CDC20 knockdown can suppress proliferation, invasion, and metastasis while enhancing apoptosis of C33A cells, which is closely related with the regulation of the Wnt/β-Catenin signaling pathway.
Humans ; Uterine Cervical Neoplasms/metabolism* ; Female ; Cdc20 Proteins/genetics* ; Cell Proliferation ; Animals ; Cell Movement ; Neoplasm Invasiveness ; Apoptosis ; Mice, Nude ; beta Catenin/metabolism* ; CRISPR-Cas Systems ; Mice ; Cell Line, Tumor ; Gene Knockout Techniques ; Neoplasm Metastasis

Anxiety disorder is a major symptom of autism spectrum disorder (ASD) with a comorbidity rate of ~40%. However, the neural mechanisms of the emergence of anxiety in ASD remain unclear. In our study, we found that hyperactivity of basolateral amygdala (BLA) pyramidal neurons (PNs) in Shank3 InsG3680 knock-in (InsG3680^+/+) mice is involved in the development of anxiety. Electrophysiological results also showed increased excitatory input and decreased inhibitory input in BLA PNs. Chemogenetic inhibition of the excitability of PNs in the BLA rescued the anxiety phenotype of InsG3680^+/+ mice. Further study found that the diminished control of the BLA by medial prefrontal cortex (mPFC) and optogenetic activation of the mPFC-BLA pathway also had a rescue effect, which increased the feedforward inhibition of the BLA. Taken together, our results suggest that hyperactivity of the BLA and alteration of the mPFC-BLA circuitry are involved in anxiety in InsG3680^+/+ mice.
Animals ; Prefrontal Cortex/metabolism* ; Basolateral Nuclear Complex/metabolism* ; Mice ; Anxiety/metabolism* ; Nerve Tissue Proteins/genetics* ; Male ; Gene Knock-In Techniques ; Pyramidal Cells/physiology* ; Mice, Transgenic ; Neural Pathways/physiopathology* ; Mice, Inbred C57BL ; Microfilament Proteins

The efficient production of L-glutamate is dependent on the product's rapid efflux, hence researchers have recently concentrated on artificially modifying its transport system and cell membrane wall structure. Considering the unique composition and structure of the cell wall of Corynebacterium glutamicum, we investigated the effects of CmpLs on L-glutamate synthesis and transport in SCgGC7, a constitutive L-glutamate efflux strain. First, the knockout strains of CmpLs were constructed, and it was confirmed that the deletion of CmpL1 and CmpL4 significantly improved the performance of L-glutamate producers. Next, temperature-sensitive L-glutamate fermentation with the CmpL1 and CmpL4 knockout strains were carried out in 5 L bioreactors, where the knockout strains showcased temperature-sensitive characteristics and enhanced capacities for L-glutamate production under high temperatures. Notably, the CmpL1 knockout strain outperformed the control strain in terms of L-glutamate production, showing production and yield increases of 69.2% and 55.3%, respectively. Finally, the intracellular and extracellular metabolites collected at the end of the fermentation process were analyzed. The modification of CmpLs greatly improved the L-glutamate excretion and metabolic flux for both L-glutamate production and transport. Additionally, the CmpL1 knockout strain showed decreased accumulation of downstream metabolites of L-glutamate and intermediate metabolites of tricarboxylic acid (TCA) cycle, which were consistent with its high L-glutamate biosynthesis capacity. In addition to offering an ideal target for improving the stability and performance of the industrial strains for L-glutamate production, the functional complementarity and redundancy of CmpLs provide a novel target and method for improving the transport of other metabolites by modification of the cell membrane and cell wall structures in C. glutamicum.
Corynebacterium glutamicum/genetics* ; Glutamic Acid/biosynthesis* ; Fermentation ; Metabolic Engineering ; Bacterial Proteins/metabolism* ; Bioreactors/microbiology* ; Gene Knockout Techniques

The protein kinase A/protein kinase G/protein kinase C-family (AGC kinase family) of eukaryotes is involved in regulating numerous biological processes. The 3-phosphoinositide- dependent protein kinase 1 (PDK1), is a conserved serine/threonine kinase in eukaryotes. To understand the roles of PDK1 homologous genes in cell death and immunity in tetraploid Nicotiana tabacum, the previuosly generated transgenic CRISPR/Cas9 lines, in which 5-7 alleles of the 4 homologous PDK1 genes (NtPDK1a/1b/1c/1d homologs) simultaneously knocked out, were used in this study. Our results showed that the hypersensitive response (HR) triggered by transient overexpression of active Pto (Pto^Y207D) or soybean GmMEKK1 was significantly delayed, whereas the resistance to Pseudomonas syrangae pv. tomato DC3000 (Pst DC3000) and tobacco mosaic virus (TMV) was significantly elevated in these partial knockout lines. The elevated resistance to Pst DC3000 and TMV was correlated with the elevated activation of NtMPK6, NtMPK3, and NtMPK4. Taken together, our results indicated that NtPDK1s play a positive role in cell death but a positive role in disease resistance, likely through negative regulation of the MAPK signaling cascade.
Nicotiana/virology* ; Disease Resistance/genetics* ; Plant Diseases/immunology* ; Plants, Genetically Modified/genetics* ; Gene Knockout Techniques ; Plant Proteins/genetics* ; CRISPR-Cas Systems ; Protein Serine-Threonine Kinases/genetics* ; 3-Phosphoinositide-Dependent Protein Kinases/genetics* ; Pyruvate Dehydrogenase Acetyl-Transferring Kinase ; Tobacco Mosaic Virus/pathogenicity*

This study established the mouse podocyte clone-5 (MPC5) with Smad3 knockout and studied the effect of transforming growth factor-beta 1 (TGF-β1) on the dedifferentiation of the MPC5 cells with Smad3 knockout, aiming to provide a cell tool for studying the role of Smad3 in mouse podocytes. The single-guide RNA (sgRNA) sequence targeting Smad3 was designed according to the principles of CRISPR/Cas9 design. The pX458-Smad3 vector was constructed and introduced into competent cells, and then the vector was extracted and used to transfect MPC5 cells. The successfully transfected cells were sorted by a flow cytometer. After single-cell clone expansion, PCR amplification of sequences adjacent to the edition site of Smad3 and sequencing were performed to identify potential cells with gene knockout. Western blotting was employed to verify the knockout efficiency of Smad3. Finally, the effect of Smad3 knockout on TGF-β1-induced dedifferentiation of MPC5 cells was analyzed by reverse transcription-polymerase chain reacting (RT-PCR), Western blotting, and the immunofluorescence method. The sgRNA was designed to target the fifth exon of Smad3. EGFP expression was observed 24 h after transfection of the pX458-Smad3 plasmid into MPC5 cells, with the transfection efficiency of 0.1% as determined by flow cytometry. From the transfected cells, 21 cell clones were obtained through flow cytometric sorting and single-cell clone expansion. PCR amplification and sequencing of the region around the sgRNA target site in Smad3 identified two cell clones with biallelic frameshift mutations. Western blotting results confirmed the absence of Smad3 expression in these clones, indicating successful establishment of the MPC5 cell line with Smad3 knockout. In normal MPC5 cells, TGF-β1 stimulation promoted the expression of fibrosis-related genes fibronectin and Col1a1 (collagen I) and inhibited the expression of the podocyte marker proteins synaptopodin and podocin, which suggested epithelial-mesenchymal transition and podocyte injury. However, in the two MPC5 cell lines with Smad3 knockout, TGF-β1-induced expression of epithelial-mesenchymal transition markers was significantly suppressed. The MPC5 cell lines with Smad3 knockout that were constructed by CRISPR/Cas9 provide a valuable cell model for functional studies of Smad3 protein and highlight the critical role of Smad3 in cell dedifferentiation.
Animals ; Smad3 Protein/genetics* ; CRISPR-Cas Systems/genetics* ; Mice ; Podocytes/metabolism* ; Transforming Growth Factor beta1/pharmacology* ; Cell Line ; Gene Knockout Techniques ; RNA, Guide, CRISPR-Cas Systems/genetics*