OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with Hereditary spastic paraplegia type 3A (SPG3A) and the genotype-phenotype correlation. METHODS: A three-generation pedigree presented at Huantai Maternal and Child Health Care Hospital in March 2021 was selected as the study subject. Whole-exome sequencing (WES) and pedigree analysis was carried out. Candidate variant was validated by Sanger sequencing of the members from the pedigree. Haplotype analysis was used to trace the origin of the variant, and pathogenicity was rated based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: 2025-12). RESULTS: A c.1024C>T (p.Pro342Ser) variant of the ATL1 was identified in the four affected members, including the proband, but none of the three unaffected relatives. Haplotype analysis suggested that the variant was derived from the proband's mother and has co-segregated with the disease phenotype. Based on the guidelines of the ACMG, it was classified as likely pathogenic. CONCLUSION The ATL1 c.1024C>T (p.Pro342Ser) variant probably underlay the pathogenesis in this pedigree. Above finding has enriched the mutational spectrum of ATL1 and phenotypic spectrum of SPG3A in the Chinese population, and enabled genetic counseling for this pedigree.
Humans ; Pedigree ; Spastic Paraplegia, Hereditary/genetics* ; Male ; Female ; Asian People/genetics* ; Adult ; Haplotypes ; Membrane Proteins/genetics* ; Exome Sequencing ; GTP-Binding Proteins/genetics* ; Mutation ; Middle Aged ; China ; Genetic Association Studies ; East Asian People

OBJECTIVES: To investigate the regulatory role of Ral guanine nucleotide dissociation stimulator-like 1 (RGL1) in metastasis of colorectal cancer (CRC). METHODS: We analyzed the differential expression of RGL1 between metastatic and non-metastatic CRC in GEO database, and examined its expression in 25 patients with metastatic CRC and 25 patients with non-metastatic CRC treated in Zhujiang Hospital between January, 2020 and December, 2022 using quantitative PCR (qPCR) and immunohistochemistry. HCT116 cell lines with stable RGL1 overexpression and SW480 cells with RGL1 knockdown were established using lentiviral vecors, and the changes in invasion and migration abilities of the cells were assessed using Transwell invasion and migration assays. The transduced cells were injected into the serosa of the cecum of nude mice, and tumor growth and liver metastasis were observed 8 weeks later. Fibronectin adhesion assays and immunofluorescence experiments were employed to assess the relationship between RGL1 and focal adhesion formation, and co-immuno-precipitation assays were performed to explore the interaction between RGL1 and GTPase activation. RESULTS: Compared with non-metastatic CRC, metastatic CRC showed significantly upregulated expression of RGL1. HCT116 cells overexpressing RGL1 exhibited obviously enhanced migration and invasion in vitro with increased capacity for liver metastasis in nude mice. RGL1 overexpression strongly accelerated focal adhesion assembly, facilitated the formation of motile focal adhesions, and enhanced the binding of activated CDC42/RAC1 complex to RGL1. CONCLUSIONS RGL1 is highly expressed in metastatic CRC and promotes distant metastasis of CRC by activating the CDC42/RAC1 complex to facilitate the formation of motile focal adhesions. These findings suggest that RGL1 can potentially serve as a therapeutic target for CRC metastasis.
Humans ; Colorectal Neoplasms/metabolism* ; cdc42 GTP-Binding Protein/metabolism* ; Animals ; Mice, Nude ; rac1 GTP-Binding Protein/metabolism* ; Cell Movement ; Mice ; Focal Adhesions/metabolism* ; Neoplasm Metastasis ; Cell Line, Tumor ; HCT116 Cells ; Up-Regulation ; Neoplasm Invasiveness ; Adaptor Proteins, Signal Transducing ; Female ; Rho Guanine Nucleotide Exchange Factors

Endosomes are characterized by the presence of various phosphoinositides that are essential for defining the membrane properties. However, the interplay between endosomal phosphoinositides metabolism and innate immunity is yet to be fully understood. Here, our findings highlight the evolutionary continuity of RAB-10/Rab10's involvement in regulating innate immunity. Upon infection of Caenorhabditis elegans with Pseudomonas aeruginosa, an increase in RAB-10 activity was observed in the intestine. Conversely, when RAB-10 was absent, the intestinal diacylglycerols (DAGs) decreased, and the animal's response to the pathogen was impaired. Further research revealed that UNC-16/JIP3 acts as an RAB-10 effector, facilitating the recruitment of phospholipase EGL-8 to endosomes. This leads to a decrease in endosomal phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and an elevation of DAGs, as well as the activation of the PMK-1/p38 MAPK innate immune pathway. It is noteworthy that the dimerization of UNC-16 is a prerequisite for its interaction with RAB-10(GTP) and the recruitment of EGL-8. Moreover, we ascertained that the rise in RAB-10 activity, due to infection, was attributed to the augmented expression of LET-413/Erbin, and the nuclear receptor NHR-25/NR5A1/2 was determined to be indispensable for this increase. Hence, this study illuminates the significance of endosomal PI(4,5)P2 catabolism in boosting innate immunity and outlines an NHR-25-mediated mechanism for pathogen detection in intestinal epithelia.
Animals ; Caenorhabditis elegans/genetics* ; Endosomes/immunology* ; Caenorhabditis elegans Proteins/immunology* ; Phosphatidylinositol 4,5-Diphosphate/immunology* ; Immunity, Innate ; Pseudomonas aeruginosa/immunology* ; rab GTP-Binding Proteins/genetics* ; Diglycerides/metabolism*

OBJECTIVE: To explore the improvement effect of electroacupuncture (EA) based on Xingnao Kaiqiao acupuncture (acupuncture for regaining consciousness and opening orifices) on cognitive impairment in mice with Parkinson's disease (PD), and to explore its regulatory mechanisms on the kinesin family member 5A (KIF5A)/mitochondrial Rho GTPase 1 (Miro1) pathway and mitophagy in prefrontal cortical neurons. METHODS: A total of 70 male C57BL/6J mice of clean grade were randomly divided into a normal group (12 mice), a sham operation group (12 mice), and a model pre-screening group (46 mice). Unilateral stereotaxic injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle was adopted to establish the PD model in the model pre-screening group. Twenty-four mice after successful modeling were randomly selected and divided into a model group and an EA group, 12 mice in each one. In the EA group, acupuncture was applied at "Shuigou" (GV26) and bilateral "Sanyinjiao" (SP6) and "Neiguan" (PC6), ipsilateral "Sanyinjiao" (SP6) and "Neiguan" (PC6) were connected to EA respectively, with disperse-dense wave, 5 Hz/20 Hz in frequency, 0.5 mA in current intensity, 20 min a time, 6 times a week for 30 days. Cognitive function was assessed by Y-maze and Morris water maze tests; morphology of prefrontal cortex was observed by H.E. staining; reactive oxygen species (ROS) level in prefrontal cortex was detected by fluorescence probe method; mitochondrial morphology and autophagosome ultrastructure were observed by transmission electron microscopy; the mRNA expression of tyrosine hydroxylase (TH) was detected by quantitative real-time PCR; the protein expression of TH, KIF5A, Miro1, p62, Parkin and PTEN induced kinase 1 (PINK1) was detected by Western blot. RESULTS: Compared with the sham operation group, both the model group and the EA group exhibited increased rotation number of per minute (P<0.001). Compared with the sham operation group, in the model group, the novel arm exploration time of Y-maze test was shortened (P<0.001), the escape latency of Morris water maze test was prolonged (P<0.05) and the platform crossing number of Morris water maze test was reduced (P<0.01); in the prefrontal cortex, the number of cellular vacuole and neurons with karyopyknosis was increased (P<0.001), and mitochondrial autophagosomes could be observed; in the prefrontal cortex, the relative expression of ROS was increased (P<0.001), the protein and mRNA expression of TH was decreased (P<0.001), the protein expression of Miro1, PINK1, Parkin was increased (P<0.001, P<0.01), the protein expression of KIF5A and p62 was decreased (P<0.001). Compared with the model group, in the EA group, the novel arm exploration time of Y-maze test was prolonged (P<0.01), the escape latency of Morris water maze test was shortened (P<0.05) and the platform crossing number of Morris water maze test was increased (P<0.05); in the prefrontal cortex, the number of cellular vacuole and neurons with karyopyknosis was decreased (P<0.001), and the number of mitochondrial autophagosomes reduced and the mitochondrial morphology was improved; in the prefrontal cortex, the relative expression of ROS was decreased (P<0.01), the protein and mRNA expression of TH was increased (P<0.001, P<0.01), the protein expression of Miro1, PINK1, Parkin was decreased (P<0.001, P<0.01, P<0.05), the protein expression of KIF5A and p62 was increased (P<0.01, P<0.05). CONCLUSION Xingnao Kaiqiao electroacupuncture effectively alleviates cognitive impairment and damage of neuronal function in PD mice, its mechanism may be related to the regulation of KIF5A/Miro1 pathway, hence reducing the mitophagy in prefrontal cortical neurons.
Animals ; Electroacupuncture ; Male ; Mice ; Parkinson Disease/physiopathology* ; Cognitive Dysfunction/psychology* ; Kinesins/genetics* ; Humans ; Mitophagy ; Mice, Inbred C57BL ; rho GTP-Binding Proteins/genetics* ; Mitochondria/genetics* ; Prefrontal Cortex/metabolism*

Cardiovascular diseases are the leading cause of mortality, posing a significant threat to human health due to the high incidence rate. Atherosclerosis, a chronic inflammatory disease, serves as the primary pathological basis for most such conditions. The incidence of atherosclerosis continues to rise, but its pathogenesis has not been fully elucidated. As an important member of the small GTPase superfamily, Ras-association proximate 1 (Rap1) is an important molecular switch involved in the regulation of multiple physiological functions including cell differentiation, proliferation, and adhesion. Rap1 achieves the utility of the molecular switch by cycling between Rap1-GTP and Rap1-GDP. Rap1 may influence the occurrence and development of atherosclerosis in a cell-specific manner. This article summarizes the potential role and mechanism of Rap1 in the progression of atherosclerosis in different cells, aiming to provide new therapeutic targets and strategies for clinical intervention.
Humans ; Atherosclerosis/metabolism* ; rap1 GTP-Binding Proteins/physiology* ; Animals ; Cell Differentiation ; Cell Adhesion ; Cell Proliferation

Objective This study aims to investigate the expression, phenotypic changes, and mechanisms of action of guanylate-binding protein 2 (GBP2) in the process of silica-induced pulmonary fibrosis. Methods The expression and localization of GBP2 in silicotic lung tissue were detected by immunohistochemical staining and immunofluorescence. An in vitro cell model was constructed, and methods such as Western blot and real-time quantitative reverse transcription polymerasechain reaction were utilized to investigate the function of GBP2 in different cell lines following silica stimulation. The mechanism of action of GBP2 in various cell lines was elucidated using Western blot analysis. Results GBP2 was highly expressed in the lung tissue of patients with silicosis. Immunohistochemical staining and immunofluorescence have revealed that GBP2 was localized in macrophages and epithelial cells. In vitro cell experiments demonstrated that silicon dioxide stimulated THP-1 cells to activate the c-Jun pathway through GBP2, promoting the secretion of inflammatory factors and facilitating the occurrence of M2 macrophage polarization. In epithelial cells, GBP2 promoted the occurrence of epithelial to mesenchymal transition (EMT) by upregulating Krueppel-like factor 8 (KLF8). Conclusion GBP2 not only activates c-Jun in macrophages to promote the production of inflammatory factors and the occurrence of M2 macrophage polarization, but also activates the transcription factor KLF8 in epithelial cells to induce EMT, collectively promoting the progression of silicosis.
Humans ; Silicosis/genetics* ; Macrophages/cytology* ; Epithelial Cells/pathology* ; GTP-Binding Proteins/physiology* ; Epithelial-Mesenchymal Transition ; Disease Progression ; Cell Line ; Male

Objective To investigate the effect and mechanism of baicalin on blood lipid metabolism and immune function in rats with gestational diabetes mellitus (GDM). Methods Female rats fed with high-fat and high-sugar diet and male rats fed with ordinary diet were caged together to prepare pregnant rats, and the GDM rat model was established by intraperitoneal injection of streptozotocin (35 mg/kg). GDM rats were randomly divided into a model group, a fasudil (FA) (RhoA/RocK inhibitor) group (10 mg/kg), low-dose (100 mg/kg) and high-dose (200 mg/kg) baicalin groups, and a high-dose baicalin combined with LPA (RhoA/RocK activator) group (200 mg/kg baicalin+1 mg/kg LPA ), with 12 rats in each group. Another 12 pregnant rats fed with high-fat and high-sugar diet were selected as the control group. After 2 weeks of corresponding drug intervention in each group, the level of fasting blood glucose (FBG) was detected by blood glucose meter. The level of fasting insulin (FINS) in serum was detected by ELISA, and the insulin resistance index (HOMA-IR) was calculated. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) in serum, and the levels of immunomodulator tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and IL-10 in peripheral blood were detected by the kit. The histopathological changes of liver were observed by HE staining. The proportion of T lymphocyte subsets in peripheral blood was detected by flow cytometry. The mRNA and protein expressions of Ras homolog gene family member A (RhoA), Rho associated coiled-coil forming protein kinase 1 (ROCK1), and ROCK2 in liver tissue were detected by real-time quantitative PCR and Western blot. Results Compared with the control group, the levels of FBG, FINS, HOMA-IR, ALT, AST, TG, TC, and LDL-C in serum, the levels of TNF-α, IL-6, the percentage of CD8⁺T cell in peripheral blood, and the mRNA and protein expression of RhoA, ROCK1, and ROCK2 in liver tissue in the model group were higher; the level of HDL-C in serum, the percentage of IL-10 levels, CD3⁺T cells, CD4⁺T cell, and CD4⁺T/CD8⁺T ratio in peripheral blood were lower. Compared with the model group, the levels of FBG, FINS, HOMA-IR, ALT, AST, TG, TC, and LDL-C in serum, the levels of TNF-α, IL-6, the percentage of CD8⁺T cell in peripheral blood, and the mRNA and protein expression of RhoA, ROCK1, and ROCK2 in liver tissue in the the FA group and low-dose and high-dose baicalin groups were lower; the level of HDL-C in serum, IL-10 level, the percentage of CD3⁺T cells, CD4⁺T cell, and CD4⁺T/CD8⁺T ratio in peripheral blood were higher. LPA could obviously weaken the improvement effects of baicalin on blood lipid metabolism and immune function in GDM rats. Conclusion Baicalin may improve blood lipid metabolism and immune function in GDM rats by inhibiting the RhoA/ROCK pathway.
Animals ; Female ; Diabetes, Gestational/metabolism* ; Pregnancy ; rho-Associated Kinases/genetics* ; Flavonoids/pharmacology* ; Rats ; rhoA GTP-Binding Protein/genetics* ; Lipid Metabolism/drug effects* ; Male ; Signal Transduction/drug effects* ; Rats, Sprague-Dawley ; Blood Glucose/metabolism* ; Lipids/blood* ; Tumor Necrosis Factor-alpha/blood* ; rho GTP-Binding Proteins

OBJECTIVE: To investigate the effect of inhibition of RAB27 protein family, which plays a pivotal role in exosome secretion, on biological behaviors of triple-negative breast cancer cells. METHODS: Quantitative real-time PCR and Western blotting were used to examine the expressions of RAB27 family and exosome secretion in 3 triple-negative breast cancer cell lines (MDA-MB-231, MDA-MB-468, and Hs578T) and a normal breast epithelial cell line (MCF10A). The effect of small interfering RNA (siRNA)-mediated silencing of RAB27a and RAB27b on exosome secretion in the 3 breast cancer cell lines was detected using Western blotting, and the changes in cell proliferation, invasion and adhesion were evaluated. RESULTS: Compared with normal breast epithelial cells, the 3 triple-negative breast cancer cell lines exhibited more active exosome secretion (P < 0.001) and showed significantly higher expressions of RAB27a and RAB27b at both the mRNA and protein levels (P < 0.01). Silencing of RAB27a in the breast cancer cells significantly down-regulated exosome secretion (P < 0.001), while silencing of RAB27b did not significantly affect exosome secretion. The 3 breast cancer cell lines with RAB27a silencing-induced down-regulation of exosome secretion showed obvious inhibition of proliferation, invasion and adhesion (P < 0.01) as compared with the cell lines with RAB27b silencing. CONCLUSION RAB27a plays central role in the exosome secretion in triple-negative breast cancer cells, and inhibiting RAB27a can inhibit the proliferation, invasion and adhesion of the cells.
Humans ; rab GTP-Binding Proteins/metabolism* ; Triple Negative Breast Neoplasms ; Cell Line, Tumor ; rab27 GTP-Binding Proteins/metabolism* ; RNA, Small Interfering/genetics* ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic

OBJECTIVE: To explore the interaction between Tubulin beta 4B class IVb (TUBB4B) and Agtpbp1/cytosolic carboxypeptidase- like1 (CCP1) in mouse primary spermatocytes (GC-2 cells) and the role of TUBB4B in regulating the development of GC-2 cells. METHODS: Lentiviral vectors were used to infect GC-2 cells to construct TUBB4B knockdown and negative control (NC-KD) cells. The stable cell lines with TUBB4B overexpression (Tubb4b-OE) and the negative control (NC-OE) cells were screened using purinomycin. RT-qPCR and Western blotting were used to verify successful cell modeling and explore the relationship between TUBB4B and CCP1 expressions in GC-2 cells. The effects of TUBB4B silencing and overexpression on the proliferation and cell cycle of GC-2 cells were evaluated using CCK8 assay and flow cytometry. The signaling pathway proteins showing significant changes in response to TUBB4B silencing or overexpression were identified using Western blotting and immunofluorescence assay and then labeled for verification at the cellular level. RESULTS: Both TUBB4B silencing and overexpression in GC-2 cells caused consistent changes in the mRNA and protein expressions of CCP1 (P < 0.05). Similarly, TUBB4B expression also showed consistent changes at the mRNA and protein after CCP1 knockdown and restoration (P < 0.05). TUBB4B knockdown and overexpression had no significant effect on proliferation rate or cell cycle of GC-2 cells, but caused significant changes in the key proteins of the nuclear factor kappa-B (NF-κB) signaling pathway (p65 and p-p65) and the mitogen-activated protein kinase (MAPK) signaling pathway (ErK1/2 and p-Erk1/2) (P < 0.05); CCP1 knockdown induced significant changes in PolyE expression in GC-2 cells (P < 0.05). CONCLUSIONS TUBB4B and CCP1 interact via a mutual positive regulation mechanism in GC-2 cells. CCP-1 can deglutamize TUBB4B, and the latter is involved in the regulation of NF-κB and MAPK signaling pathways in primary spermatocytes.
Animals ; Male ; Mice ; GTP-Binding Proteins/metabolism* ; Mitogen-Activated Protein Kinases/metabolism* ; NF-kappa B/metabolism* ; RNA, Messenger ; Serine-Type D-Ala-D-Ala Carboxypeptidase/metabolism* ; Signal Transduction ; Spermatocytes ; Tubulin/genetics*

OBJECTIVE: To investigate the inhibitory effect of miR-125b-5p on proliferation and migration of osteosarcoma and the role of RAB3D in mediating this effect. METHODS: The expression level of miR-125b-5p was detected by qRT-PCR in a normal bone cell line (hFOB1.19) and in two osteosarcoma OS cell lines (MG63 and HOS). A miR-125b-5p mimic or inhibitor was transfected in the osteosarcoma cell lines via liposome and the changes in cell proliferation and migration were detected with EDU and Transwell experiments. Bioinformatic analysis was conducted for predicting the target gene of miR-125b-5p, and the expression level of RAB3D in hFOB1.19, MG63, and HOS cells was detected by Western blotting. In the two osteosarcoma cell lines transfected with miR-125b-5p mimic or inhibitor, the expression levels of RAB3D mRNA and protein in osteosarcoma cells were examined with qRT-PCR and Western blotting. The effects of RAB3D overexpression, RAB3D knockdown, or overexpression of both miR-125b-5p and RAB3D on the proliferation and migration of cells were assessed using EDU and Transwell experiments. RESULTS: The two osteosarcoma cell lines had significantly lower expression levels of miR-125b-5p (P < 0.05). Bioinformatic analysis predicted that RAB3D was a possible target gene regulated by miR-125b-5p. In osteosarcoma cells, overexpression of miR-125b-5p significantly lowered the expression of RAB3D protein (P < 0.05); inhibiting miR-125b-5p expression significantly decreased RAB3D expression only at the protein level (P < 0.05) without obviously affecting its mRNA level. Modulation of miR-125b-5p and RAB3D levels produced opposite effects on proliferation and migration of osteosarcoma cells, and in cells with overexpression of both miR-125b-5p and RAB3D, the effect of RAB3D on cell proliferation and migration was blocked by miR-125b-5p overexpression (P < 0.05). CONCLUSION Overexpression of miR-125b-5p inhibits the proliferation and migration of osteosarcoma cells by regulating the expression of RAB3D at the post-transcriptional level.
Humans ; Bone Neoplasms/genetics* ; Cell Proliferation ; MicroRNAs/genetics* ; Osteosarcoma/genetics* ; rab3 GTP-Binding Proteins/genetics* ; RNA, Messenger