Acute mitochondrial damage and the energy crisis following axonal injury highlight mitochondrial transport as an important target for axonal regeneration. Syntaphilin (Snph), known for its potent mitochondrial anchoring action, has emerged as a significant inhibitor of both mitochondrial transport and axonal regeneration. Therefore, investigating the molecular mechanisms that influence the expression levels of the snph gene can provide a viable strategy to regulate mitochondrial trafficking and enhance axonal regeneration. Here, we reveal the inhibitory effect of microRNA-146b (miR-146b) on the expression of the homologous zebrafish gene syntaphilin b (snphb). Through CRISPR/Cas9 and single-cell electroporation, we elucidated the positive regulatory effect of the miR-146b-snphb axis on Mauthner cell (M-cell) axon regeneration at the global and single-cell levels. Through escape response tests, we show that miR-146b-snphb signaling positively regulates functional recovery after M-cell axon injury. In addition, continuous dynamic imaging in vivo showed that reprogramming miR-146b significantly promotes axonal mitochondrial trafficking in the pre-injury and early stages of regeneration. Our study reveals an intrinsic axonal regeneration regulatory axis that promotes axonal regeneration by reprogramming mitochondrial transport and anchoring. This regulation involves noncoding RNA, and mitochondria-associated genes may provide a potential opportunity for the repair of central nervous system injury.
Animals ; Zebrafish ; MicroRNAs/genetics* ; Nerve Regeneration/physiology* ; Mitochondria/metabolism* ; Zebrafish Proteins/genetics* ; Axons/metabolism* ; Signal Transduction/physiology* ; Axonal Transport/physiology* ; Nerve Tissue Proteins/genetics*

The angiogenic response is essential for the repair of ischemic brain tissue. Integrin α6 (Itga6) expression has been shown to increase under hypoxic conditions and is expressed exclusively in vascular structures; however, its role in post-ischemic angiogenesis remains poorly understood. In this study, we demonstrate that mice with endothelial cell-specific knockout of Itga6 exhibit reduced neovascularization, reduced pericyte coverage on microvessels, and accelerated breakdown of microvascular integrity in the peri-infarct area. In vitro, endothelial cells with ITGA6 knockdown display reduced proliferation, migration, and tube-formation. Mechanistically, we demonstrated that ITGA6 regulates post-stroke angiogenesis through the PI3K/Akt-eNOS-VEGFA axis. Importantly, the specific overexpression of Itga6 in endothelial cells significantly enhanced neovascularization and enhanced the integrity of microvessels, leading to improved functional recovery. Our results suggest that endothelial cell Itga6 plays a crucial role in key steps of post-stroke angiogenesis, and may represent a promising therapeutic target for promoting recovery after stroke.
Animals ; Nitric Oxide Synthase Type III/metabolism* ; Mice ; Proto-Oncogene Proteins c-akt/metabolism* ; Integrin alpha6/genetics* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Stroke/pathology* ; Vascular Remodeling/physiology* ; Vascular Endothelial Growth Factor A/metabolism* ; Mice, Knockout ; Signal Transduction/physiology* ; Mice, Inbred C57BL ; Male ; Neovascularization, Physiologic/physiology*

Sucrose non-fermenting 1-related protein kinase 1 (SnRK1) is one of the highly conserved Ca²⁺ non-dependent serine/threonine protein kinases, playing a crucial role in regulating the stress responses, growth, and development of plants. SnRK1 is a three-subunit complex, and it is involved in responding to the signaling transduction induced by low-energy/low-sugar conditions. SnRK1 responds biotic and abiotic stress conditions (such as salt, drought, low/high temperatures, and diseases) through phosphorylation of key metabolic enzymes and regulatory proteins, regulation of transcription, and interactions with other proteins. Furthermore, SnRK1 is not only involved in hormone signaling pathways mediated by abscisic acid (ABA), jasmonic acid (JA) and salicylic acid (SA), but also regulates plant autophagy by inhibiting the activity of target of rapamycin (TOR). In this review, we summarized the current results of research on the discovery, structure, and classification of plant SnRK1 and its roles in the stress responses, growth, and development of plants. Furthermore, this article proposes the directions of future research. This review provides good genetic resources and a theoretical basis for the genetic improvement and biological breeding for enhancing the stress tolerance of crops.
Stress, Physiological/physiology* ; Protein Serine-Threonine Kinases/metabolism* ; Plant Development/genetics* ; Signal Transduction ; Gene Expression Regulation, Plant ; Plant Proteins/physiology* ; Plants/metabolism* ; Arabidopsis Proteins/physiology* ; Plant Growth Regulators/metabolism*

Calcineurin B-like protein (CBL)-interacting protein kinases (CIPKs) are a group of Ser/Thr protein kinases, playing a crucial role in the growth, development, and stress responses of plants. CIPKs can undergo autophosphorylation or target the phosphorylation of other signaling factors in responses to biotic and abiotic stresses. In addition, they are involved in the signaling pathways of plant hormones such as abscisic acid (ABA), gibberellic acid (GA), ethylene (ETH), and salicylic acid (SA) to regulate plant growth and development. Furthermore, CIPKs respond to stresses such as salinity, drought, cold, and heavy metals by forming complexes through specific interactions with CBLs. In this study, we summarized the discovery, structures, classification, regulatory mechanisms, and roles of CIPKs in plant responses to stresses and made an outlook on the future research directions. This review is expected to provide genetic resources and theoretical foundations for the genetic improvement and breeding of crops with stress tolerance.
Stress, Physiological/physiology* ; Protein Serine-Threonine Kinases/genetics* ; Signal Transduction/physiology* ; Plant Growth Regulators/metabolism* ; Plant Proteins/genetics* ; Plants/metabolism*

BACKGROUND: Immunosuppression is closely related to the pathogenesis of sepsis, but the underlying mechanisms have not yet been fully elucidated. In this study, we aimed to examine the role of the Sterile Alpha Motif, Src Homology 3 domain and nuclear localization signal 1 (SAMSN1) in sepsis and elucidate its potential molecular mechanism in sepsis induced immunosuppression. METHODS: RNA sequencing databases were used to validate SAMSN1 expression in sepsis. The impact of SAMSN1 on sepsis was verified using gene knockout mice. Flow cytometry was employed to delineate how SAMSN1 affects immunity in sepsis, focusing on immune cell types and T cell functions. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated gene editing in RAW264.7 macrophages enabled interrogation of SAMSN1 's regulatory effects on essential macrophage functions, including cell proliferation and phagocytic capacity. The mechanism of SAMSN1 in the interaction between macrophages and T cells was investigated using the RAW264.7 cell line and primary cell lines. RESULTS: SAMSN1 expression was significantly increased in patients with sepsis and was positively correlated with sepsis mortality. Genetic deletion of Samsn1 in murine sepsis model improved T cell survival, elevated T cell cytolytic activity, and activated T cell signaling transduction. Concurrently, Samsn1 knockout augmented macrophage proliferation capacity and phagocytic efficiency. In macrophage, SAMSN1 binds to Kelch-like epichlorohydrin-associated protein 1 (KEAP1), causing nuclear factor erythroid 2-related factor 2 (NRF2) to dissociate from the KEAP1-NRF2 complex and translocate into the nucleus. This promotes the transcription of the coinhibitory molecules CD48/CD86/carcinoembryonic antigen related cell adhesion molecule 1 (CEACAM1), which bind to their corresponding receptors natural killer cell receptor 2B4/CD152/T cell immunoglobulin and mucin domain-containing protein 3 (TIM3) on the surface of T cells, inducing T-cell exhaustion. CONCLUSIONS SAMSN1 deletion augmented adaptive T cell immunity and macrophage phagocytic-proliferative dual function. Furthermore, it mediates the KEAP1-NRF2 axis, which affects the expression of coinhibitory molecules on macrophages, leading to T-cell exhaustion. This novel immunosuppression mechanism potentially provides a candidate molecular target for sepsis immunotherapy.
Animals ; NF-E2-Related Factor 2/metabolism* ; Mice ; Macrophages/immunology* ; Sepsis/metabolism* ; Kelch-Like ECH-Associated Protein 1/genetics* ; T-Lymphocytes/immunology* ; Humans ; Signal Transduction/physiology* ; RAW 264.7 Cells ; Mice, Knockout ; Mice, Inbred C57BL ; Male ; Flow Cytometry ; T-Cell Exhaustion

BACKGROUND: Pancreatic cancer is a lethal malignancy prone to gemcitabine resistance. The single-strand selective monofunctional uracil DNA glycosylase (SMUG1), which is responsible for initiating base excision repair, has been reported to predict the outcomes of different cancer types. However, the function of SMUG1 in pancreatic cancer is still unclear. METHODS: Gene and protein expression of SMUG1 as well as survival outcomes were assessed by bioinformatic analysis and verified in a cohort from Fudan University Shanghai Cancer Center. Subsequently, the effect of SMUG1 on proliferation, cell cycle, and migration abilities of SMUG1 cells were detected in vitro . DNA damage repair, apoptosis, and gemcitabine resistance were also tested. RNA sequencing was performed to determine the differentially expressed genes and signaling pathways, followed by quantitative real-time polymerase chain reaction and Western blotting verification. The cancer-promoting effect of forkhead box Q1 (FOXQ1) and SMUG1 on the ubiquitylation of myelocytomatosis oncogene (c-Myc) was also evaluated. Finally, a xenograft model was established to verify the results. RESULTS: SMUG1 was highly expressed in pancreatic tumor tissues and cells, which also predicted a poor prognosis. Downregulation of SMUG1 inhibited the proliferation, G1 to S transition, migration, and DNA damage repair ability against gemcitabine in pancreatic cancer cells. SMUG1 exerted its function by binding with FOXQ1 to activate the Protein Kinase B (AKT)/p21 and p27 pathway. Moreover, SMUG1 also stabilized the c-Myc protein via AKT signaling in pancreatic cancer cells. CONCLUSIONS SMUG1 promotes proliferation, migration, gemcitabine resistance, and c-Myc protein stability in pancreatic cancer via protein kinase B signaling through binding with FOXQ1. Furthermore, SMUG1 may be a new potential prognostic and gemcitabine resistance predictor in pancreatic ductal adenocarcinoma.
Humans ; Pancreatic Neoplasms/pathology* ; Forkhead Transcription Factors/genetics* ; Signal Transduction/genetics* ; Animals ; Cell Line, Tumor ; Proto-Oncogene Proteins c-akt/metabolism* ; Cell Proliferation/physiology* ; Mice ; Uracil-DNA Glycosidase/genetics* ; Female ; Male ; Gemcitabine ; Mice, Nude ; Apoptosis/physiology* ; Deoxycytidine/analogs & derivatives* ; Cell Movement/genetics*

OBJECTIVE: To explore the therapeutic effect of polygonum cuspidatum glycoside on steroid-induced osteonecrosis of the femoral head(SONFH) in rats and its potential mechanism of protecting bone tissue by regulating the Janus kinase 2/signal transducer and activator of transcription 3 signaling pathway(JAK2/STAT3). METHODS: Fifty male SD rats were randomly divided into control group, model group, low-dose polygonum cuspidatum glycoside group (polygonum cuspidatum glycoside-L), high-dose polygonum cuspidatum glycoside group (polygonum cuspidatum glycoside-H), and polygonum cuspidatum glycoside-H+Colivelin (JAK2/STAT3 pathway activator) group. SONFH model was induced by lipopolysaccharide and dexamethasone. The treatment groups were given polygonum cuspidatum glycoside orally(polygonum cuspidatum glycoside-L 10 mg·kg^-1, polygonum cuspidatum glycoside-H 20 mg·kg^-1, and the polygonum cuspidatum glycoside-H+Colivelin group was injected with Colivelin (1 mg·kg^-1) intraperitoneally once a day, while the control and model groups were given an equal volume of saline for 6 weeks. The observed indicators included serum calcium(Ca), serum phosphorus (P), alkaline phosphatase, and transforming growth factor β1(TGF-β1) levels, micro-CT scanning, hematoxylin-eosin staining, and Western blot detection of JAK2/STAT3 signaling pathway and osteogenic differentiation marker genes, including Runt-related transcription factor 2 (Runx2), bone morphogenetic protein 2 (BMP2), and osteopontin (OPN) protein expression. RESULTS: Compared with the model group, the trabecular bone area percentage in the polygonum cuspidatum glycoside-L and polygonum cuspidatum glycoside-H groups was significantly increased, and the empty lacunar rate was significantly decreased (P<0.05). Micro-CT analysis showed that the bone volume fraction, trabecular number, and thickness increased, and the trabecular separation decreased in the polygonum cuspidatum glycoside-treated groups(P<0.05). Serum biochemical tests found that the serum Ca and P concentrations in the polygonum cuspidatum glycoside-L and polygonum cuspidatum glycoside-H groups were restored, the alkaline phosphatase levels decreased, and the transforming growth factor β1 levels increased (P<0.05). Western blot analysis showed that polygonum cuspidatum glycoside significantly inhibited the activation of the JAK2/STAT3 signaling pathway in the model group and promoted the expression of osteogenic differentiation marker genes such as Runx2, BMP2, and OPN (P<0.05). Compared with the polygonum cuspidatum glycoside-H group, the improvements in the polygonum cuspidatum glycoside-H+Colivelin group were somewhat weakened, indicating the importance of the JAK2/STAT3 signaling pathway in the action of polygonum cuspidatum glycoside. CONCLUSION polygonum cuspidatum glycoside promotes osteogenic differentiation, improves bone microstructure, and has significant therapeutic effects on rat SONFH by regulating the JAK2/STAT3 signaling pathway.
Animals ; Male ; Janus Kinase 2/physiology* ; Rats, Sprague-Dawley ; Rats ; Signal Transduction/drug effects* ; Glucosides/pharmacology* ; STAT3 Transcription Factor/genetics* ; Femur Head Necrosis/chemically induced* ; Stilbenes/pharmacology*

OBJECTIVE: To explore mechanisms of acid-sensing ion channel 1 (ASIC1) mediated lumbar nucleus pulposus cell apoptosis through extracellular-signalregulated protein kinase 5 (ERK5) signaling pathway and mitochondrial dysfunction pathway. METHODS: Totally 34 patients with degenerative lumbar disc herniation (LDH) admitted from January 2020 to December 2022 were collected as research objects, including 21 males and 13 females;aged from 29 to 52 years old with an average of (37.43±4.75) years old;22 patients with grade Ⅱ and 12 patients with grade Ⅳ, according to Pfirrmann grading criteria;15 patients with L_4,5 and 19 patients with L₅S₁. The expression of ASIC1 in nucleus pulposus of LDH patients was measured by immunohistochemical staining. Nucleus pulposus cells were cultured by primary culture method, identified by toluidine blue staining and immunohistochemical staining, and the expression of ASIC1 protein was located by immunofluorescence staining. According to the addition of siRNA-ASIC1, ASIC1 overexpression plasmid, and ERK5 inhibitors, the nucleus pulpocyte was divided into three groups, named as SIRNA-silenced group, overexpression group, and inhibitor group, with 3 patients in each group. Cells of each group were collected at 72 h after intervention, expression of ASIC1, ERK5, BCL-xL/BCL-2-associated Death promoter (Bad), B-cell lymphoma-2 associated X (Bax) and B-cell lymphoblast-2 gene (Bcl-2) were detected by reverse transcription-polymerase chain reaction (RT-PCR);intracellular calcium ion levels were detected by calcium ion kit, mitochondrial membrane potential was detected by JC-1 kit, and apoptosis was observed by AV-PI kit. RESULTS: In LDH patients with grade Ⅳ, nucleus pulposus tissue removed during operation revealed poor elasticity, white color and poor ductility, and immunohistochemical results showed increased ASIC1 expression. There was no significant difference in mRNA relative expression of ASIC1 between siRNA silencing group (0.31±0.03) and inhibitor group (0.39±0.05) (P>0.05). The mRNA relative expression level of ERK5 in siRNA silencing group(0.32±0.05) was significantly higher than that in inhibitor group (0.15±0.04)(P<0.05), which suggested ERK5 was the downstream molecule of ASIC1. The mRNA relative expression levels of apoptosis promoting factor Bad and Bax in siRNA silencing group and inhibitor group were lower than those in overexpression group(P<0.05), the relative expression level of anti-apoptosis factor Bcl-2 mRNA was significantly increased (P<0.05). The calcium content in overexpression group was higher than that in siRNA silencing and inhibitor groups (P<0.05), the normal proportion of mitochondrial membrane potential in overexpression group was lower than that in siRNA silencing and inhibitor group (P<0.05), and the apoptosis rate in overexpression group was higher than that in siRNA silencing and inhibitor group (P<0.05). CONCLUSION After the activation of ASIC1 channel protein, calcium ions could enter the cells and act as a second messenger molecule to regulate apoptosis of nucleus pulposus cells by ERK5 signaling pathway and mitochondrial disorder pathway.
Humans ; Acid Sensing Ion Channels/physiology* ; Male ; Female ; Apoptosis ; Middle Aged ; Adult ; Signal Transduction ; Mitogen-Activated Protein Kinase 7/physiology* ; Mitochondrial Diseases/genetics* ; Nucleus Pulposus/metabolism* ; Intervertebral Disc Degeneration/metabolism* ; Mitochondria/metabolism* ; Intervertebral Disc Displacement/genetics*

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 investigate the role and mechanism of the zinc finger protein Kruppel-like transcription factor 9 (KLF9) in the stimulation of type I interferon expression induced by herpes simplex virus type 1 (HSV-1) in macrophages. Methods Agarose Gel electrophoresis, quantitative real-time PCR (qRT-PCR) and western blot analyses were employed to detect the KLF9 relative expression in bone marrow-derived macrophages (BMDMs) from Klf9^-/- (gKO) mice and wild-type (WT) mice. RNA-seq analysis was utilized to identify the potential targeted genes upon HSV-1 stimulation in BMDMs. ELISA was used to measure the potent of IFN-β in the supernatant of BMDMs derived from gKO and WT mice after HSV-1 stimulation. qRT-PCR analysis was employed to further confirm the changes of Ifnb1 and interferon-stimulated gene (ISG) such as interferon-induced protein with tetratricopeptide repeats 1 (Ifit1), interferon-stimulated exonuclease gene 20 (Isg20), cholesterol 25-hydroxylase (Ch25h) and 2'-5' oligoadenylate synthetase-like 1 (Oasl1). Western blot was used to detect the expression of phosphorylated interferon regulatory factor-3 (p-IRF3), IRF3, phosphorylated interferon regulatory factor-7 (p-IRF7), IRF7, phosphorylated nuclear factor-kappa B p65 (p-NF-κB p65) and NF-κB p65. CUT-Tag and ChIP-qPCR assay were utilized to confirm the binding region of KLF9 in Ifnb1. Results The KLF9 expression was significantly decreased in BMDMs from gKO mice compared with that from WT mice. The RNA-seq analysis showed that Klf9 deletion in BMDMs resulted in an impaired type I interferon signaling pathway. The qRT-PCR analysis revealed that Klf9 deletion in BMDMs led to a significant decrease of Ifnb1 and ISG such as Ifit1, Ch25h and Oasl1 except Isg20. Moreover, ELISA revealed that Klf9 knockout in BMDMs resulted in a significant decrease of IFN-β secreted from BMDMs. Mechanistically, KLF9 directly binds to the promoter of Ifnb1. Conclusion KLF9 is essential for macrophages to resist HSV-1 infection.
Animals ; Kruppel-Like Transcription Factors/physiology* ; Interferon-beta/metabolism* ; Macrophages/virology* ; Mice ; Herpesvirus 1, Human/physiology* ; Mice, Knockout ; Signal Transduction ; Mice, Inbred C57BL ; Interferon Regulatory Factor-3/genetics* ; Interferon Regulatory Factor-7/genetics* ; Gene Expression Regulation