scholarly journals Circular RNA circMYL1 Inhibit Proliferation and Promote Differentiation of Myoblasts by Sponging miR-2400

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 176
Author(s):  
Ibrahim Elsaeid Elnour ◽  
Xiaogang Wang ◽  
Toremurat Zhansaya ◽  
Zhanerke Akhatayeva ◽  
Rajwali Khan ◽  
...  
Keyword(s):  
Muscle Development ◽  
Circular Rna ◽  
Cell Counting ◽  
Myoblast Differentiation ◽  
Circular Rnas ◽  
Marker Genes ◽  
Primary Myoblast ◽  
Rna Immunoprecipitation ◽  
Mrna And Protein Expression ◽  
Differentiation Marker

Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs (ncRNAs) involved in regulating skeletal muscle development by sponging miRNAs. In this study, we found that the circMYL1 expression was down-regulated during myoblast proliferation, while gradually up-regulated in myoblast differentiation. The potential role of circMYL1 was identified in the proliferation of bovine myoblast through mRNA and protein expression of proliferation marker genes (PCNA, CyclinD1, and CDK2), cell counting kit-8 assay, flow cytometry analysis, and 5-ethynyl 2′-deoxyuridine (EdU) assay. Analysis of the expression of differentiation marker genes (MyoD, MyoG, and MYH2) and immunofluorescence of Myosin heavy chain (MyHC) was used to assess cell differentiation. The proliferation analysis revealed that circMYL1 inhibited the proliferation of bovine primary myoblast. Furthermore, the differentiation analysis demonstrated that circMYL1 promoted the differentiation of bovine primary myoblast. The luciferase screening and RNA immunoprecipitation (RIP) assays found that circMYL1 could have interaction with miR-2400. Additionally, we demonstrated that miR-2400 promoted proliferation and inhibited differentiation of bovine primary myoblast, while circMYL1 may eliminate the effects of miR-2400, as showed by rescue experiments. Together, our results revealed that a novel circular RNA of circMYL1 could inhibit proliferation and promote differentiation of myoblast by sponging miR-2400.

scholarly journals Circular RNA circMYL1 inhibit proliferation and promote differentiation of myoblasts by sponging miR-2400

2020 ◽  
Author(s):  
Ibrahim E. Elnour ◽  
Xiaogang Wang ◽  
Toremurat Zhansaya ◽  
Akhatayeva Zhanerke ◽  
Rajwali Khan ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Muscle Development ◽  
Circular Rna ◽  
Cell Counting ◽  
Circular Rnas ◽  
Marker Genes ◽  
Primary Myoblast ◽  
Rna Immunoprecipitation ◽  
Mrna And Protein Expression ◽  
Differentiation Marker

Abstract Background Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs (ncRNAs) involved in regulating skeletal muscle development by sponging microRNAs (miRNAs). This study aimed to define the circMYL1 molecular mechanisms in the regulation of bovine myogenesis and to disclose its regulatory mechanism through miR-2400 interaction. Methods The potential role of circMYL1 was identified in the proliferation of bovine myoblast through mRNA and protein expression of proliferation marker genes (PCNA, CyclinD1, and CDK2), cell counting kit-8 (CCK8) assay, flow cytometry analysis, and EdU assay. Analysis of the expression of differentiation marker genes (MyoD, MyoG, and MYH2) and immunofluorescence of Myosin heavy chain (MyHC) was used to assess cell differentiation. Results The proliferation analysis revealed that circMYL1 inhibited the proliferation of bovine primary myoblast. Furthermore, the differentiation analysis demonstrated that circMYL1 promoted the differentiation of bovine primary myoblast. The luciferase screening and RNA immunoprecipitation (RIP) assays found that circMYL1 could have interaction with miR-2400. Additionally, we demonstrated that miR-2400 promoted proliferation and inhibited differentiation of bovine primary myoblast, while circMYL1 may eliminate the effects of miR-2400, as showed by rescue experiments. Conclusions Our results revealed that a novel circular RNA of circMYL1 could inhibit proliferation and promote differentiation of myoblast by sponging miR-2400.

scholarly journals Circular RNA profiling of buffalo myoblasts reveals an abundant circPICALM that promotes myoblast differentiation

2020 ◽  
Author(s):  
Mingming Song ◽  
Mengjie Chen ◽  
Kongwei Huang ◽  
Dandan Zhong ◽  
Yaling Chen ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Regeneration ◽  
Muscle Development ◽  
Expression Profiles ◽  
Muscle Growth ◽  
Circular Rna ◽  
Skeletal Muscle Regeneration ◽  
Myoblast Differentiation ◽  
Circular Rnas

Abstract Background Muscle development is a precisely orchestrated and complex process, and circular RNAs (circRNAs) has been demonstrated to play important roles in skeletal muscle growth and development. However, the regulatory functions of circRNA during buffalo muscle developmental processes have not been understood.Results In this study, Ribo-Zero RNA-Seq was performed to investigate the circRNAs expression profiles of proliferated and differentiated buffalo myoblasts. A stringent set of 3,142 circRNAs was finally characterized. Comparing the expression profiles of circRNAs revealed that 110 circRNAs were expressed differentially during myoblast differentiation. We focused on the role of a candidate circRNA, which was named circPICALM based on its host gene PICALM, and was highly (but differentially) expressed in proliferated and differentiated myoblasts. Flow cytometry, EdU incorporation, and Western blotting assays demonstrate that circPICALM promoted myoblasts proliferation and inhibited cells apoptosis. Moreover, overexpression of circPICALM promoted the differentiation of primary buffalo myoblasts. Moreover, circPICALM in vivo stimulated skeletal muscle regeneration in cardiotoxin-induced muscle injury. The RNA pulldown results showed that circPICALM could capture TUBA1B protein, revealing that circPICALM might exert its biological function by binding TUBA1B protein. Conclusions These results demonstrate that the novel non-coding regulator circPICALM induces myoblast differentiation and skeletal muscle regeneration.

scholarly journals Warburg effect-promoted exosomal circ_0072083 releasing up-regulates NANGO expression through multiple pathways and enhances temozolomide resistance in glioma

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Chenyu Ding ◽  
Xuehan Yi ◽  
Xiangrong Chen ◽  
Zanyi Wu ◽  
Honghai You ◽  
...  
Keyword(s):  
Warburg Effect ◽  
Lactate Production ◽  
Xenograft Model ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Circular Rnas ◽  
Rna Immunoprecipitation ◽  
Resistant Cells

Abstract Background Temozolomide (TMZ) resistance limits its application in glioma. Exosome can carry circular RNAs (circRNAs) to regulate drug resistance via sponging microRNAs (miRNAs). miRNAs can control mRNA expression by regulate the interaction with 3’UTR and methylation. Nanog homeobox (NANOG) is an important biomarker for TMZ resistance. Hitherto, it is unknown about the role of exosomal hsa_circ_0072083 (circ_0072083) in TMZ resistance in glioma, and whether it is associated with NANOG via regulating miRNA sponge and methylation. Methods TMZ-resistant (n = 36) and sensitive (n = 33) patients were recruited. The sensitive cells and constructed resistant cells were cultured and exposed to TMZ. circ_0072083, miR-1252-5p, AlkB homolog H5 (ALKBH5) and NANOG levels were examined via quantitative reverse transcription polymerase chain reaction and western blot. The half maximal inhibitory concentration (IC50) of TMZ, cell proliferation, apoptosis, migration and invasion were analyzed via Cell Counting Kit-8, colony formation, flow cytometry, wound healing and transwell assays. The in vivo function was assessed using xenograft model. The N6-methyladenosine (m6A) level was analyzed via methylated RNA immunoprecipitation (MeRIP). Target relationship was investigated via dual-luciferase reporter assay and RNA immunoprecipitation. Warburg effect was investigated via lactate production, glucose uptake and key enzymes expression. Exosome was isolated and confirmed via transmission electron microscopy and specific protein expression. Results circ_0072083 expression was increased in TMZ-resistant glioma tissues and cells. circ_0072083 knockdown restrained the resistance of resistant cells via decreasing IC50 of TMZ, proliferation, migration, invasion and xenograft tumor growth and increasing apoptosis. circ_0072083 silence reduced NANOG expression via blocking ALKBH5-mediated demethylation. circ_0072083 could regulate NANOG and ALKBH5 via targeting miR-1252-5p to control TMZ resistance. Warburg effect promoted the release of exosomal circ_0072083 in resistant cells. Exosomal circ_0072083 from resistant cells increased the resistance of sensitive cells to TMZ in vitro and xenograft model. Exosomal circ_0072083 level was enhanced in resistant patients, and it had a diagnostic value and indicated a lower overall survival in glioma. Conclusion Exosomal circ_0072083 promoted TMZ resistance via increasing NANOG via regulating miR-1252-5p-mediated degradation and demethylation in glioma.

scholarly journals Circular RNA circCSPP1 knockdown attenuates doxorubicin resistance and suppresses tumor progression of colorectal cancer via miR-944/FZD7 axis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lanlan Xi ◽  
Quanlin Liu ◽  
Wei Zhang ◽  
Linshan Luo ◽  
Jingfeng Song ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Tumor Growth ◽  
Circular Rna ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Protein Levels ◽  
Cell Progression ◽  
Rna Immunoprecipitation ◽  
Induced Apoptosis

Abstract Background Circular RNAs (circRNAs) have been reported to play vital roles in colorectal cancer (CRC). However, only a few circRNAs have been experimentally validated and functionally described. In this research, we aimed to reveal the functional mechanism of circCSPP1 in CRC. Methods 36 DOX sensitive and 36 resistant CRC cases participated in this study. The expression of circCSPP1, miR-944 and FZD7 were detected by quantitative real time polymerase chain reaction (qRT-PCR) and the protein levels of FZD7, MRP1, P-gp and LRP were detected by western blot. Cell proliferation, migration, invasion, and apoptosis were assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay, transwell assay, or flow cytometry analysis, respectively. The interaction between miR-944 and circCSPP1 or frizzled-7 (FZD7) was predicted by Starbase 3.0 and verified by the dual luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull down assay. Xenograft tumor assay was performed to examine the effect of circCSPP1 on tumor growth in vivo. Results The expression of circCSPP1 and FZD7 was upregulated while miR-944 expression was downregulated in doxorubicin (DOX)-resistant CRC tissues and cells. CircCSPP1 knockdown significantly downregulated enhanced doxorubicin sensitivity, suppressed proliferation, migration, invasion, and induced apoptosis in DOX-resistant CRC cells. Interestingly, we found that circCSPP1 directly downregulated miR-944 expression and miR-944 decreased FZD7 level through targeting to 3′ untranslated region (UTR) of FZD7. Furthermore, circCSPP1 mediated DOX-resistant CRC cell progression and doxorubicin sensitivity by regulating miR-944/FZD7 axis. Besides, circCSPP1 downregulation dramatically repressed CRC tumor growth in vivo. Conclusion Our data indicated that circCSPP1 knockdown inhibited DOX-resistant CRC cell growth and enhanced doxorubicin sensitivity by miR-944/FZD7 axis, providing a potential target for CRC therapy.

scholarly journals Circular RNA circCCDC66 Contributes to Malignant Phenotype of Osteosarcoma by Sponging miR-338-3p to Upregulate the Expression of PTP1B

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Deng Xiang ◽  
Yugang Li ◽  
Yanshui Lin
Keyword(s):  
Cell Proliferation ◽  
Molecular Mechanism ◽  
Cell Lines ◽  
Rapid Development ◽  
Circular Rna ◽  
Molecular Medicine ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Tissue Samples

In recent years, the mechanism of cancer research has become hotspots of life science and medicine, especially due to the rapid development of molecular medicine and bioinformatics research. Similarly, the molecular mechanism also has received increasing attention in osteosarcoma (OS) research. Also, a considerable amount of research confirmed that circular RNAs (circRNAs) could regulate cancer cell growth and metastasis. This study aimed to explore the effect of a circRNA, circCCDC66, on OS and reveal its potential molecular mechanism. High circCCDC66 expression level was found in OS patient-derived tissue samples and OS cell lines by qRT-PCR. The abilities cell proliferation and metastatic of U2OS and SW1353 cells were then assessed by Cell Counting Kit-8 and transwell assay, respectively. The interaction between circCCDC66 and its target miRNAs were verified by the dual-luciferase reporter assay. Through functional experiments, we found that circCCDC66 knockdown promoted the inhibition of cell proliferation and metastatic of OS cell lines. From mechanistic perspective, circCCDC66 upregulated PTP1B by sponging miR-338-3p. Collectively, our findings demonstrated that circCCDC66 contributed to malignant behaviors of OS cells by miR-338-3p/PTP1B pathway, which suggested circCCDC66/miR-338-3p/PTP1B axis might be a potential therapeutic target.

scholarly journals circ-SIRT1 Promotes Colorectal Cancer Proliferation and EMT by Recruiting and Binding to eIF4A3

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Xiangjie Wang ◽  
Shuang Liu ◽  
Bin Xu ◽  
Yabin Liu ◽  
Peng Kong ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Noncoding Rna ◽  
Circular Rna ◽  
Cell Counting ◽  
Cancer Proliferation ◽  
Rna Immunoprecipitation ◽  
Invasive Capacity ◽  
Underlying Mechanisms ◽  
Sirt1 Gene ◽  
Related Proteins

Circular RNA (circRNA), a recently identified type of endogenous noncoding RNA, has been implicated in the occurrence and development of a variety of tumors; however, whether circ-SIRT1, derived from pre-mRNA of the parental SIRT1 gene, is involved in colorectal cancer (CRC) remains unknown, as do the potential underlying mechanisms. The expression of circ-SIRT1 in CRC cells and tissue was detected by RT-qPCR. Colony formation and Cell Counting Kit-8 assays were used to evaluate the effect of circ-SIRT1 knockdown on the proliferative ability of CRC cells. Wound healing and Transwell assays were used to assess the effect of circ-SIRT1 knockdown on the migratory and invasive capacity of CRC cells. RNA immunoprecipitation and RNA pull-down assays were employed to validate the binding of circ-SIRT1 to EIF4A3. Western blot was used to identify the changes in the expression of EIF4A3 and EMT-related proteins. The RT-qPCR results showed that circ-SIRT1 was highly expressed in CRC cells and tissue and was positively correlated with the depth of tumor invasion. Knocking down circ-SIRT1 inhibited the proliferation and invasion of CRC cells and EMT. We further found that EIF4A3 could bind to circ-SIRT1, and that overexpressing circ-SIRT1 decreased the abundance of EIF4A3 at the mRNAs of the EMT marker proteins N-cadherin and vimentin. Combined, our findings suggested that circ-SIRT1 regulates the expression of EMT-related proteins by preventing EIF4A3 recruitment to the respective mRNAs. Our results further indicate that circ-SIRT1 functions as an oncogene in CRC by promoting the proliferation, invasion, and EMT of CRC cells through the circ-SIRT1/EIF4A3/N-cadherin/vimentin pathway.

scholarly journals Circular RNA hsa_circ_0081343 promotes trophoblast cell migration and invasion and inhibits trophoblast apoptosis by regulating miR-210-5p/DLX3 axis

2021 ◽  
Author(s):  
Jiansheng Xie ◽  
Hui Wang ◽  
Caiqun Luo ◽  
Xiaoxia Wu ◽  
Jianming Zhang ◽  
...  
Keyword(s):  
Luciferase Activity ◽  
Circular Rna ◽  
Extravillous Trophoblast ◽  
Migration And Invasion ◽  
Circular Rnas ◽  
Protein Levels ◽  
Apoptosis Protein ◽  
Luciferase Activity Assay ◽  
Rna Immunoprecipitation

Abstract Background: Various circular RNAs (circRNAs) are dysregulated in the placenta of fetal growth restriction fetuses, but their role and regulatory mechanisms have not been fully elucidated. Herein, we aimed to elucidate the role of hsa_circ_0081343 in regulating the migration, invasion, and apoptosis in the human extravillous trophoblast HTR-8 cells.Methods: circRNA and miRNA levels were examined using quantitative real-time PCR (RT-PCR). Overexpression plasmid constructs and siRNA were used to overexpress and knockdown hsa_circ_0081343, respectively. Transwell assay and flow cytometry analysis were performed to evaluate the effect of hsa_circ_0081343 or miR-210-5p on migration, invasion, and apoptosis. Protein levels were analyzed using western blot. Dual luciferase activity assay and anti-AGO2 RNA immunoprecipitation (RIP) assays were performed to identify the relationship between miR-210-5p and hsa_circ_0081343.Results: Hsa_circ_0081343 expression was significantly downregulated in 37 FGR placental tissues as compared to healthy placental control tissues. Hsa_circ_0081343 overexpression possibly inhibits apoptosis by downregulating the expression of cleaved caspase 3 and caspase 9 and alleviates the migration and invasion of HTR-8 cells by inducing the expression of MMP2 and MMP9. The dual luciferase activity and anti-AGO2 RIP assay results showed that hsa_circ_0081343 binds to miR-210-5p. miR-210-5p overexpression eliminated the effect of hsa_circ_0081343 overexpression in HTR-8 cells. Finally, DLX3 was identified as a direct target of miR-210-5p. Conclusions: Hsa_circ_0081343 regulates the migration, invasion, and apoptosis of HTR-8 cells via the hsa-miR-210-5p/DLX3 axis. Thus, hsa_circ_0081343 plays a key role in the etiology and pathogenesis of FGR implicating its importance as a novel candidate for targeted FGR therapy.

scholarly journals Circular RNA screening identifies circMYLK4 as a regulator of fast/slow myofibers in porcine skeletal muscles

2020 ◽  
Author(s):  
Haigang Cao ◽  
Jieming Liu ◽  
Tianning Du ◽  
Yihao Liu ◽  
Xiaoyu Zhang ◽  
...  
Keyword(s):  
Muscle Development ◽  
Target Genes ◽  
Enrichment Analysis ◽  
Functional Enrichment Analysis ◽  
Circular Rna ◽  
Functional Enrichment ◽  
Differentially Expressed ◽  
Marker Genes ◽  
Type Conversion ◽  
Myofiber Type

Abstract Background: The myofiber type is related to the quality of meat; specifically, slow-oxidized myofiber helps to increase the tenderness and juiciness of meat. An increasing number of studies have shown that circRNAs play a key role in skeletal muscle development. However, the key circRNAs that regulate myofiber types and their roles are still poorly understood.Results: A total of 40757 circRNAs were identified from the longissimus dorsi (LD) and the soleus (Sol) muscles, of which 10388 were co-expressed in the two muscles. Further analysis found 181 differentially expressed circRNAs in the LD compared with Sol. Functional enrichment analysis showed that target genes of differentially expressed circRNA-sponge miRNAs were enriched in the AMPK, FoxO and PI3K-Akt signaling pathways. In addition, we focused on a novel circRNA—circMYLK4. CircMYLK4 significantly increased the mRNA and protein levels of slow muscle marker genes and caused the flesh to turn red.Conclusion: Our study laid an essential foundation for further research on circRNAs in myofiber type conversion and the achievement of higher meat quality.

scholarly journals Circular RNA circASPM Promotes the Progression of Glioblastoma by Acting as a Competing Endogenous RNA to Regulate miR-130b–3p/E2F1 Axis

2020 ◽  
Author(s):  
Dianqi Hou ◽  
Zhenlin Wang ◽  
Haimeng Li ◽  
Juan Liu ◽  
Yaohua Liu ◽  
...  
Keyword(s):  
Western Blotting ◽  
Circular Rna ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Primary Malignancy ◽  
Rna Immunoprecipitation ◽  
Western Blotting Assay

Abstract background: Glioblastoma Multiform (GBM) is the primary malignancy with the highest incidence and worst prognosis in the adult CNS. Circular RNAs (circRNAs) are a novel and widely diverse class of endogenous non-coding RNAs that can promote or inhibit gliomagenesis. Our study aimed to explore the role of circASPM in GBM and its molecular mechanism.Methods: Levels of circASPM, miR-130b-3p and E2F1 were determined by quantitative real-time PCR (qRT-PCR) or western blotting assay. MTS, Edu, neurospheres formation and extreme limiting dilution assays were used to detect the tumorigenesis and proliferation of GSCs in vitro. The interactions between miR-130b-3p and circASPM or E2F1 was demonstrated via qPCR, western blotting, dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Xenograft experiments was used to analyze tumor growth in vivo.Results: CircASPM was overexpressed in GBM and could promote the tumorigenesis and proliferation of GSCs both in vitro and in vivo. Mechanistically, circASPM up-regulated the expression of E2F1 in GSCs via miR-130b-3p sponging. We furtherly demonstrated that circAPSM could promote the GSCs proliferation via E2F1 up-regulating. Therefore, our study identified a novel circRNA and its possible mechanism in the development and tumorigenesis of GBM.Conclusions: CircASPM can promote GBM progression via regulating miR-130b-3p/E2F1 axis, suggesting that circAPSM could provide an effective biomarker for GBM diagnosis and prognostic evaluation and possibly being used for molecular targeted therapy.

scholarly journals Lnc-GD2H Promotes Proliferation by Forming a Feedback Loop With c-Myc and Enhances Differentiation Through Interacting With NACA to Upregulate Myog in C2C12 Myoblasts

2021 ◽  
Vol 9 ◽  
Author(s):  
Rui Chen ◽  
Si Lei ◽  
Yanling She ◽  
Shanyao Zhou ◽  
Huacai Shi ◽  
...  
Keyword(s):  
Muscle Regeneration ◽  
Feedback Loop ◽  
Quantitative Polymerase Chain Reaction ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Myoblast Differentiation ◽  
Marker Genes ◽  
C2c12 Myoblast ◽  
Myoblast Proliferation

In the present study, the roles of a novel long non-coding RNA (lncRNA), lnc-GD2H, in promoting C2C12 myoblast proliferation and differentiation and muscle regeneration were investigated by quantitative polymerase chain reaction, western blotting, Cell Counting Kit-8, 5-ethynyl-2′-deoxyuridine (EdU), immunofluorescence staining, luciferase reporter, mass spectrometry, pulldown, chromatin immunoprecipitation, RNA immunoprecipitation assay, wound healing assays, and cardiotoxin (CTX)-induced muscle injury assays. It was observed that lnc-GD2H promoted myoblast proliferation as evidenced by the enhancement of the proliferation markers c-Myc, CDK2, CDK4, and CDK6, percentage of EdU-positive cells, and rate of cell survival during C2C12 myoblast proliferation. Additional experiments confirmed that c-Myc bound to the lnc-GD2H promoter and regulated its transcription. lnc-GD2H promoted cell differentiation with enhanced MyHC immunostaining as well as increased expression of the myogenic marker genes myogenin (Myog), Mef2a, and Mef2c during myoblast differentiation. Additional assays indicated that lnc-GD2H interacted with NACA which plays a role of transcriptional regulation in myoblast differentiation, and the enrichment of NACA at the Myog promoter was impaired by lnc-GD2H. Furthermore, inhibition of lnc-GD2H impaired muscle regeneration after CTX-induced injury in mice. lnc-GD2H facilitated the expression of proliferating marker genes and formed a feedback loop with c-Myc during myoblast proliferation. In differentiating myoblasts, lnc-GD2H interacted with NACA to relieve the inhibitory effect of NACA on Myog, facilitating Myog expression to promote differentiation. The results provide evidence for the role of lncRNAs in muscle regeneration and are useful for developing novel therapeutic targets for muscle disorders.

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