OBJECTIVE: To investigate the effects of LncRNA SNHG20 on epithelial mesenchymal transition (EMT) and microtubule formation in human oral squamous cell carcinoma (OSCC) cells through targeted regulation of the miR-520c-3p/RAB22A pathway. METHODS: After real-time fluorescence quantitative detection of LncRNA SNHG20, miR-520c-3p, RAB22A mRNA expression levels in OSCC tissues and cells, dual luciferase reporter assay was used to detect the relationship between the three. OSCC cells were randomly separated into control group, sh-NC group, sh-SNHG20 group, sh-SNHG20+anti NC group, and sh-SNHG20+anti miR-520c-3p group. Western blotting was used to detect the expression of N-cadherin, vimentin, and E-cadherin proteins in the OSCC cells. The morphology of HSC-3 cells was observed under microscope. Changes in the number of microtubules formed were detected. The effect of LncRNA SNHG20 on the growth of OSCC tumors and the expression levels of LncRNA SNHG20, miR-520c-3p and RAB22 A in the transplanted tumors were detected by nude mice tumorigenesis experiment. RESULTS: LncRNA SNHG20 and RAB22A mRNA were upregulated in the OSCC tissues and cells, while miR-520c-3p was downregulated (P < 0.05). There were binding sites between LncRNA SNHG20 and miR-520c-3p, RAB22A and miR-520c-3p, which had targeted regulation relationship. Compared with the sh-NC group, the sh-SNHG20 group had fewer stromal like cells, more epithelial like cells, incomplete microtubule structure, and fewer nodules. LncRNA SNHG20, RAB22A, N-Cadherin, and vimentin were downregulated, while miR-520c-3p and E-cadherin were upregulated (P < 0.05). Compared with the sh-SNHG20+anti-NC group, the sh-SNHG20+anti-miR-520c-3p group had a higher number of stromal like cells, a lower number of epithelioid cells, tighter microtubule arrangement, and more microtubule nodules. miR-520c-3p and E-cadherin were downregulated, while RAB22A, N-cadherin, and vimentin were upregulated (P < 0.05). The transplanted tumor of OSCC in sh-SNHG20 group was smaller and lower than that in sh-NC group. The expression levels of LncRNA SNHG20 and RAB22A in the transplanted tumor tissues were lower than those in sh-NC group, and the expression level of miR-520c-3p was higher than that in sh-NC group (P < 0.05). CONCLUSION LncRNA SNHG20 promotes epithelial-mesenchymal transition and microtubule formation in human oral squamous cell carcinoma cells by targeting the miR-520c-3p/RAB22A pathway. Inhibiting the expression of LncRNA SNHG20 can target and regulate the miR-520c-3p/RAB22A pathway to inhibit EMT and microtubule formation in OSCC cells.
Humans ; RNA, Long Noncoding/genetics* ; MicroRNAs/metabolism* ; rab GTP-Binding Proteins/metabolism* ; Epithelial-Mesenchymal Transition/genetics* ; Cell Line, Tumor ; Carcinoma, Squamous Cell/metabolism* ; Animals ; Microtubules/metabolism* ; Mouth Neoplasms/genetics* ; Mice, Nude ; Mice ; Gene Expression Regulation, Neoplastic ; Mice, Inbred BALB C

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 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

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

Extracellular deposition of β-amyloid (Aβ) and intracellular hyperphosphorylated tau are the predominant pathological changes in Alzheimer's disease (AD). Increasing evidence demonstrates a critical role of a variety of small GTPases, namely Ras-related proteins (Rabs), in the pathogenesis of AD. As crucial regulators of intracellular membrane trafficking, alteration in Rab protein expression and function represents one of the primary factors contributing to the abnormal membrane trafficking in AD. Additionally, the Rab GTPases are also involved in the development of Aβ, tau and other pathological changes associated with AD. In this article, we conduct a comprehensive review on the primary functions of multiple Rab proteins and their involvement in the pathogenesis of AD.
Humans ; Alzheimer Disease ; rab GTP-Binding Proteins/metabolism* ; Amyloid beta-Peptides/metabolism* ; tau Proteins/metabolism*

Objective: To investigate the effects of continuing exercise and load-bearing interval exercise on skeletal muscle tissue cell morphology, Ras-related proteins 5 (Rab5) mRNA and protein expression and glucose metabolism in skeletal muscle of type 2 diabetic mellitus (T2DM) rats. Methods: Eight SD rats were selected as controls group (CR), the others SD rats were fed with high fat and high sugar diet for 6 weeks before injecting STZ (35 mg/kg) to construct the T2DM model. Twenty-four T2DM rats were randomly devided into T2DM model group (DRM), continuing exercise group (DCRE) and load-bearing interval exercise group (DWRE), 8 rats in each group. DCRE exercise protocol, that was 15 m/min (10 min), 20 m/min (40 min), 15 m/min (10 min), during the first 1～2 weeks, and 18 m/min (10 min), 25 m/min (40 min), 15 m/min (10 min), during the second 3～8 weeks. DWRE exercise protocol: load weight 15% / 1～2 weeks, 30% / 3～4 weeks, 45% / 5～8 weeks, with 15 m/min (5 min), 12 groups and 3 min rest between groups. After 8 weeks, pathological and morphological changes of skeletal muscle were observed by HE. Rab5 and Glucose transporte 4 (GLUT4) mRNA expressions of skeletal muscle were tested by qRT-PCR. Rab5 protein expression in skeletal muscle was tested by immunofluorescence histochemistry and Western blot, and plasma Rab5 and Glycosylated Hemoglobin (GHb) concentrations were detected by ELISA. Results: Comparison with CR, DRM showed pathological damage of skeletal muscle, the expressions of Rab5 mRNA, protein and GLUT4 mRNA were all decreased in skeletal muscle (P＜0.01), the serum levels of Rab5 and GHb were both significantly elevated (P＜0.01). Comparison with DRM, both DCRE and DWRE significantly improved pathological damages of skeletal muscle, the expressions of Rab5 mRNA, protein and GLUT4 mRNA were all increased in skeletal muscle (P＜ 0.05, P＜0.01), the serum levels of Rab5 and GHb were decreased (P＜0.05, P＜0.01), and there was no statistical difference between DCRE and DWRE groups (P＞0.05). Conclusion: Two exercise modes can improve the pathological injury of skeletal muscle in type 2 diabetic rats, and enhance GLUT4 transport capacity by improving the expression of Rab5 gene and protein in skeletal muscle, and alleviate the imbalance of glucose metabolism homeostasis in skeletal muscle. However, there was no significant difference between the effects of two exercise modes on Rab5 protein and glucose metabolism in skeletal muscle.
Animals ; Diabetes Mellitus, Experimental/metabolism* ; Diabetes Mellitus, Type 2/metabolism* ; Glucose/metabolism* ; Glycated Hemoglobin ; Insulin ; Muscle, Skeletal/metabolism* ; Physical Conditioning, Animal/methods* ; RNA, Messenger/metabolism* ; Rats ; Rats, Sprague-Dawley ; rab5 GTP-Binding Proteins/metabolism*

As a member of the Ras superfamily, Rab proteins are small GTP-binding proteins. In the process of endocytosis of macromolecules and substances delivery between organelles, Rab proteins act on vesicle formation, transport, tethering and fusion by recruiting their effectors, therefore being key regulatory factors in vesicle trafficking. Disturbance of localizations and functions of Rab proteins and their effectors are involved in the pathogenesis of several diseases. This review focuses on the main functions of Rab proteins and their possible roles in the onset and progression of neurodegenerative diseases including Parkinson's disease, Alzheimer's disease, and Huntington's disease.
Cell Movement ; Endocytosis ; Humans ; Neurodegenerative Diseases ; Protein Transport ; rab GTP-Binding Proteins/metabolism*

OBJECTIVE: To explore the clinical and genetic characteristics of a child featuring developmental delay. METHODS: The child was subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: Whole genome sequencing revealed that the child has carried compound heterozygous variants c.2607-1G>C and c.899 + 2dupT of the RAB3GAP1 gene, which were respectively derived from her mother and father. CONCLUSION A rare case of Warburg micro syndrome type 1 was diagnosed. The phenotype of the child was consistent with the literature, in addition with dysplasia of palatine arch, prominent high palatal arch and tooth dysplasia. Above finding has provided a basis for genetic counseling and prenatal diagnosis for the family.
Abnormalities, Multiple/genetics* ; Adult ; Cataract/genetics* ; Child ; Cornea/abnormalities* ; Female ; Humans ; Hypogonadism/genetics* ; Intellectual Disability/genetics* ; Male ; Microcephaly/genetics* ; Mutation ; Optic Atrophy/genetics* ; Whole Exome Sequencing ; rab3 GTP-Binding Proteins/genetics*

Animals ; Autoantigens ; genetics ; metabolism ; Cell Line, Tumor ; Golgi Apparatus ; genetics ; metabolism ; Golgi Matrix Proteins ; Insulin-Secreting Cells ; metabolism ; Membrane Proteins ; genetics ; metabolism ; Proinsulin ; genetics ; metabolism ; Rats ; rab1 GTP-Binding Proteins ; genetics ; metabolism

Endocytosis is differentially regulated by hypoxia-inducible factor-1alpha (HIF-1alpha) and phospholipase D (PLD). However, the relationship between HIF-1alpha and PLD in endocytosis is unknown. HIF-1alpha is degraded through the prolyl hydroxylase (PHD)/von Hippel-Lindau (VHL) ubiquitination pathway in an oxygen-dependent manner. Here, we show that PLD1 recovers the decrease in epidermal growth factor receptor (EGFR) endocytosis induced by HIF-1alpha independent of lipase activity via the Rab5-mediated endosome fusion pathway. EGF-induced interaction of PLD1 with HIF-1alpha, PHD and VHL may contribute to EGFR endocytosis. The pleckstrin homology domain (PH) of PLD1 itself promotes degradation of HIF-1alpha, then accelerates EGFR endocytosis via upregulation of rabaptin-5 and suppresses tumor progression. These findings reveal a novel role of the PLD1-PH domain as a positive regulator of endocytosis and provide a link between PLD1 and HIF-1alpha in the EGFR endocytosis pathway.
Animals ; Blood Proteins/chemistry/*metabolism ; Endocytosis ; Female ; HEK293 Cells ; HT29 Cells ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism ; Mice, Nude ; Neoplasms/genetics/metabolism/pathology ; Phospholipase D/chemistry/*metabolism ; Phosphoproteins/chemistry/*metabolism ; Protein Structure, Tertiary ; Receptor, Epidermal Growth Factor/*metabolism ; Signal Transduction ; *Up-Regulation ; Vesicular Transport Proteins/*genetics/metabolism ; rab5 GTP-Binding Proteins/*metabolism