Uqcr11 alleviates oxidative stress and apoptosis after traumatic brain injury.

Traumatic brain injury (TBI) is a major cause of death and disability that involves brain dysfunction due to external forces. Here, we found lower levels of Ubiquinol-cytochrome c reductase, complex III subunit XI (Uqcr11) expression in the cerebral cortex of TBI mice. A neuronal damage model was constructed using H2O2 or hypoxia reoxygenation (H/R) in vitro. We found that Uqcr11 overexpression attenuated the H2O2-or H/R-induced damage by preventing oxidative stress and neuronal apoptosis in HT22 cells. Moreover, up-regulated Uqcr11 contributed to the restoration of motor, learning, and memory in C57BL/6 mice after TBI, and its underlying mechanism may be associated with promoting neuron survival and inhibited oxidative stress. Collectively, our findings demonstrated that oxidative stress as well as neuronal apoptosis can be ameliorated post-TBI by Uqcr11 overexpression, which provides a potential therapeutic target for TBI.

miR-6076 targets BCL6 in SH-SY5Y cells to regulate amyloid-ß-induced neuronal damage.

Amyloid-ß1-42 (Aß1-42 ) is strongly associated with Alzheimer's disease (AD). The aim of this study is to elucidate whether and how miR-6076 participates in the modulation of amyloid-ß (Aß)-induced neuronal damage. To construct the neuronal damage model, SH-SY5Y cells were treated with Aß1-42 . By qRT-PCR, we found that miR-6076 is significantly upregulated in Aß1-42 -treated SH-SY5Y cells. After miR-6076 inhibition, p-Tau and apoptosis levels were downregulated, and cell viability was increased. Through online bioinformatics analysis, we found that B-cell lymphoma 6 (BCL6) was a directly target of miR-6076 via dual-luciferase reporter assay. BCL6 overexpression mediated the decrease in elevated p-Tau levels and increased viability in SH-SY5Y cells following Aß1-42 treatment. Our results suggest that down-regulation of miR-6076 could attenuate Aß1-42 -induced neuronal damage by targeting BCL6, which provided a possible target to pursue for prevention and treatment of Aß-induced neuronal damage in AD.

Lama2 And Samsn1 Mediate the Effects of Brn4 on Hippocampal Neural Stem Cell Proliferation and Differentiation.

The transcription factor Brn4 exhibits vital roles in the embryonic development of the neural tube, inner ear, pancreas islet, and neural stem cell differentiation. Our previous studies have shown that Brn4 promotes neuronal differentiation of hippocampal neural stem cells (NSCs). However, its mechanism is still unclear. Here, starting from the overlapping genes between RNA-seq and ChIP-seq results, we explored the downstream target genes that mediate Brn4-induced hippocampal neurogenesis. There were 16 genes at the intersection of RNA-seq and ChIP-seq, among which the Lama2 and Samsn1 levels can be upregulated by Brn4, and the combination between their promoters and Brn4 was further determined using ChIP and dual luciferase reporter gene assays. EdU incorporation, cell cycle analysis, and CCK-8 assay indicated that Lama2 and Samsn1 mediated the inhibitory effect of Brn4 on the proliferation of hippocampal NSCs. Immunofluorescence staining, RT-qPCR, and Western blot suggested that Lama2 and Samsn1 mediated the promoting effect of Brn4 on the differentiation of hippocampal NSCs into neurons. In conclusion, our study demonstrates that Brn4 binds to the promoters of Lama2 and Samsn1, and they partially mediate the regulation of Brn4 on the proliferation inhibition and neuronal differentiation promotion of hippocampal NSCs.

miR-6216 regulates neural stem cell proliferation by targeting RAB6B.

Neural stem cells (NSCs) are a class of self-renewing, multipotent and undifferentiated progenitor cells that retain the capacity to both glial and neuronal lineages. MicroRNAs (miRNAs) are small non-coding RNAs that play an important role in stem cell fate determination and self-renewal. Our previous RNA-seq data indicated that the expression of miR-6216 was decreased in denervated hippocampal exosomes compared with normal. However, whether miR-6216 participates in regulating NSC function remains to be elucidated. In this study, we demonstrated that miR-6216 negatively regulates RAB6B expression. Forced overexpression of miR-6216 inhibited NSC proliferation, and overexpression of RAB6B promoted NSC proliferation. These findings suggest that miR-6216 played an important role in regulating NSC proliferation via targeting RAB6B, and improve the understanding of the miRNA-mRNA regulatory network that affects NSC proliferation.

MiR-130a-3p regulates neural stem cell differentiation in vitro by targeting Acsl4.

In the adult mammalian brain, neural stem cells (NSCs) are the precursor cells of neurons that contribute to nervous system development, regeneration, and repair. MicroRNAs (miRNAs) are small non-coding RNAs that regulate cell fate determination and differentiation by negatively regulating gene expression. Here, we identified a post-transcriptional mechanism, centred around miR-130a-3p that regulated NSC differentiation. Importantly, overexpressing miR-130a-3p promoted NSC differentiation into neurons, whereas inhibiting miR-130a-3p function reduced the number of neurons. Then, the quantitative PCR, Western blot and dual-luciferase reporter assays showed that miR-130a-3p negatively regulated acyl-CoA synthetase long-chain family member 4 (Acsl4) expression. Additionally, inhibition of Acsl4 promoted NSC differentiation into neurons, whereas silencing miR-130a-3p partially suppressed the neuronal differentiation induced by inhibiting Acsl4. Furthermore, overexpressing miR-130a-3p or inhibiting Acsl4 increased the levels of p-AKT, p-GSK-3ß and PI3K. In conclusion, our results suggested that miR-130a-3p targeted Acsl4 to promote neuronal differentiation of NSCs via regulating the Akt/PI3K pathway. These findings may help to develop strategies for stem cell-mediated treatment for central nervous system diseases.

circRNA Acbd6 promotes neural stem cell differentiation into cholinergic neurons via the miR-320-5p-Osbpl2 axis.

Neural stem cells (NSCs) persist in the dentate gyrus of the hippocampus into adulthood and are essential for both neurogenesis and neural circuit integration. Exosomes have also been shown to play vital roles in regulating biological processes of receptor cells as a medium for cell-to-cell communication signaling molecules. The precise molecular mechanisms of exosome-mediated signaling, however, remain largely unknown. Here, we found that exosomes produced by denervated hippocampi following fimbria-fornix transection could promote the differentiation of hippocampal neural precursor cells into cholinergic neurons in coculture with NSCs. Furthermore, we found that 14 circular RNAs (circRNAs) were upregulated in hippocampal exosomes after fimbria-fornix transection using high-throughput RNA-Seq technology. We further characterized the function and mechanism by which the upregulated circRNA Acbd6 (acyl-CoA-binding domain-containing 6) promoted the differentiation of NSCs into cholinergic neurons using RT-quantitative PCR, Western blot, ELISA, flow cytometry, immunohistochemistry, and immunofluorescence assay. By luciferase reporter assay, we demonstrated that circAcbd6 functioned as an endogenous miR-320-5p sponge to inhibit miR-320-5p activity, resulting in increased oxysterol-binding protein-related protein 2 expression with subsequent facilitation of NSC differentiation. Taken together, our results suggest that circAcbd6 promotes differentiation of NSCs into cholinergic neurons via miR-320-5p/oxysterol-binding protein-related protein 2 axis, which contribute important insights to our understanding of how circRNAs regulate neurogenesis.

miR-103-3p targets Ndel1 to regulate neural stem cell proliferation and differentiation.

The regulation of adult neural stem cells (NSCs) is critical for lifelong neurogenesis. MicroRNAs (miRNAs) are a type of small, endogenous RNAs that regulate gene expression post-transcriptionally and influence signaling networks responsible for several cellular processes. In this study, miR-103-3p was transfected into neural stem cells derived from embryonic hippocampal neural stem cells. The results showed that miR-103-3p suppressed neural stem cell proliferation and differentiation, and promoted apoptosis. In addition, miR-103-3p negatively regulated NudE neurodevelopment protein 1-like 1 (Ndel1) expression by binding to the 3' untranslated region of Ndel1. Transduction of neural stem cells with a lentiviral vector overexpressing Ndel1 significantly increased cell proliferation and differentiation, decreased neural stem cell apoptosis, and decreased protein expression levels of Wnt3a, ß-catenin, phosphor-GSK-3ß, LEF1, c-myc, c-Jun, and cyclin D1, all members of the Wnt/ß-catenin signaling pathway. These findings suggest that Ndel1 is a novel miR-103-3p target and that miR-103-3p acts by suppressing neural stem cell proliferation and promoting apoptosis and differentiation. This study was approved by the Animal Ethics Committee of Nantong University, China (approval No. 20200826-003) on August 26, 2020.

MiR-674-5p Suppresses the Proliferation and Migration of Glioma Cells by Targeting Cul4b.

Glioma multiforme (GBM) is the most common malignant primary brain tumors. Despite the considerable advances in GBM treatment, it is still one of the most lethal forms of brain tumor. New clinical biomarkers and therapeutic targets are immediately required. MicroRNAs (miRNAs) are a class of small, evolutionarily conserved noncoding RNAs and have emerged as the key regulators of many cancers. Here in this study, we showed that miR-674-5p was probably an important regulator of glioma cell growth. After the transfection with miR-674-5p mimic or inhibitor, we found that the expression level of miR-674-5p was negatively related with cell proliferation and migration in C6 cells. Based on the prediction of the target genes of miR-674-5p on the website, we chose Cullin 4B (Cul4b), a gene upregulated in GBM, and proved that it was a target of miR-674-5p. In addition, we explored the role of miR-674-5p in glioma growth in vivo. Taken together, the present study indicated that miR-674-5p suppressed glioma cell proliferation and migration by targeting Cul4b.

P4HA2 promotes cell proliferation and migration in glioblastoma.

Glioblastoma (GBM) is a primary malignant tumor characterized by high infiltration and angiogenesis in the brain parenchyma. Glioma stem cells (GSCs), a heterogeneous GBM cell type with the potential for self-renewal and differentiation to tumor cells, are responsible for the high malignancy of GBM. The purpose of the present study was to investigate the roles of significantly differentially expressed genes between GSCs and GBM cells in GBM progression. The gene profiles GSE74304 and GSE124145, containing 10 GSC samples and 12 GBM samples in total, were obtained from the Gene Expression Omnibus (GEO) database. The overlapping differentially expressed genes were identified with GEO2R tools and Venn software online. Subsequently, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis was performed on the 41 upregulated and 142 downregulated differentially expressed genes in GSCs compared with in GBM cells via the DAVID website. Protein-protein interaction and module analyses in Cytoscape with the STRING database revealed 21 hub genes that were downregulated in GSCs compared with in GBM cells. Survival analysis conducted via the GEPIA2 website revealed that low expression levels of the hub genes prolyl 4-hydroxylase subunit α2 (P4HA2), TGF-ß induced, integrin subunit α3 and thrombospondin 1 were associated with significantly prolonged survival time in patients with GBM. Further experiments were performed focusing on P4HA2. Reverse transcription-quantitative PCR was used to detect P4HA2 gene expression. In agreement with the bioinformatics analysis, P4HA2 expression was higher in U87 cells than in GSCs. Cell Counting Kit-8, EdU incorporation, cell cycle analysis, wound healing and Transwell assays demonstrated that the cell proliferation and migration increased after P4HA2 overexpression and decreased after P4HA2-knockdown. In conclusion, the present study demonstrated that low P4HA2 expression in GSCs promoted GBM cell proliferation and migration, suggesting that P4HA2 may act as a switch in the transition from GSCs to GBM cells.

CircHECTD1 Regulates Cell Proliferation and Migration by the miR-320-5p/SLC2A1 Axis in Glioblastoma Multiform.

Glioblastoma multiform (GBM) is the most common and malignant primary brain cancer in adults, and thus, novel potential therapeutic targets for diagnosis and treatment are urgently needed. Circular RNAs (circRNAs) are a class of widespread and diverse endogenous RNAs that have been suggested as potential critical mediators during progression of various tumors. In this study, we investigated the involvement of circHECTD1 in GBM progression. CircHECTD1 Lentivirus, miR-320-5p mimic, and SLC2A1 Lentivirus were transduced into cancer cells independently or together. circHECTD1, miR-320-5p, and SLC2A1 level were detected by qRT-PCR. Western blot and qRT-PCR were applied to measure the expression of SLC2A1, CyclinD1, CDK2, and PCNA. Flow cytometry, EdU, colony formation, Transwell and wound-healing assays were conducted to assess cell proliferation and migration. Luciferase reporter assays were performed to determine the effect of miR-320-5p on circHECTD1 or SLC2A1. Xenograft experiments were implemented to evaluate tumor growth in vivo. CircHECTD1 expression led to the promotion of proliferation and migration of GBM cells. In addition, circHECTD1 acted as a ceRNA to interact with miR-320-5p, which targeted the solute carrier family 2 member 1 (SLC2A1). In vivo experiments also revealed that circHECTD1 promoted tumor growth. Collectively, our findings showed that the circHECTD1-miR-320-5p-SLC2A1 regulatory pathway promoted the progression of GBM, suggesting that circHECTD1 may be a therapeutic target for GBM.

miR-33-3p Regulates PC12 Cell Proliferation and Differentiation In Vitro by Targeting Slc29a1.

MicroRNA-33-3p (miR-33-3p) has been widely investigated for its roles in lipid metabolism and mitochondrial function; however, there are few studies on miR-33-3p in the context of neurological diseases. In this study, we investigated the functional role of miR-33-3p in rat pheochromocytoma PC12 cells. A miR-33-3p mimic was transduced into PC12 cells, and its effects on proliferation, apoptosis, and differentiation were studied using the MTS assay, EdU labeling, flow cytometry, qRT-PCR, western blot, ELISA, and immunofluorescence. We found that miR-33-3p significantly suppressed PC12 cell proliferation, but had no effect on apoptosis. Furthermore, miR-33-3p promoted the differentiation of PC12 cells into Tuj1-positive and choline acetyltransferase-positive neuron-like cells. Mechanistically, miR-33-3p repressed the expression of Slc29a1 in PC12 cells. Importantly, knocking down Slc29a1 in PC12 cells inhibited proliferation and induced differentiation into neuron-like cells. In conclusion, this study showed that miR-33-3p regulated Slc29a1, which in turn controlled the proliferation and differentiation of PC12 cells. Thus, we hypothesize that the miR-33-3p/Slc29a1 axis could be a promising therapeutic target for recovering neurons and the cholinergic nervous system.

Expression and function of Ndel1 during the differentiation of neural stem cells induced by hippocampal exosomesticle.

BACKGROUND: In the brain of adult mammals, neural stem cells persist in the subventricular zone of the lateral ventricle and the subgranular zone of the dentate gyrus, which are specialized niches with proliferative capacity. Most neural stem cells are in a quiescent state, but in response to extrinsic stimuli, they can exit from quiescence and become reactivated to produce new neurons, so neural stem cells are considered to be a potential source for cell replacement therapy of many nervous system diseases. We characterized the expression of Ndel1 during the differentiation of neural stem cells induced by hippocampus exosomes, and assessed the effect of Ndel1 on neural stem cells differentiation. METHODS: Hippocampal exosomes were isolated and extracted, and co-cultured exosomes with neural stem cells. Western blot, flow cytometry, and immunofluorescence analyses were used to analyze expression of neuronal markers. Further, utilizing high-throughput RNA sequencing technology, we found that nudE neurodevelopment protein 1-like 1 was significantly upregulated in exosomes derived from denervated hippocampus, and then characterized its mechanism and function during neural stem cells differentiation by qRT-PCR, western blot, flow cytometry, and immunofluorescence analyses. RESULTS: Our results revealed that exosomes of denervated hippocampus promoted the differentiation of neural stem cells into neuron. Hence, we identified that nudE neurodevelopment protein 1-like 1 was significantly upregulated and highly expressed in the nervous system. In addition, we found that miR-107-3p may regulate neural stem cell differentiation by targeting Ndel1. CONCLUSIONS: Our results revealed that deafferentation of the hippocampal exosomes co-cultured with neural stem cells could promote them to differentiate into neurons. Hence, we found that miR-107-3p may regulate neural stem cells differentiation by targeting Ndel1. Importantly, Ndel1 enhanced spatial learning and hippocampal neurogenesis in rats after fimbria fornix transection in vivo. These findings set the stage for a better understanding of neurogenesis, a process that 1 day may inspire new treatments for central nervous system diseases.

The role of hippocampal niche exosomes in rat hippocampal neurogenesis after fimbria-fornix transection.

Exosomes transfer signaling molecules such as proteins, lipids, and RNAs to facilitate cell-cell communication and play an important role in the stem cell microenvironment. In previous work, we demonstrated that rat fimbria-fornix transection (FFT) enhances neurogenesis from neural stem cells (NSCs) in the subgranular zone (SGZ). However, how neurogenesis is modulated after denervation remains unknown. Here, we investigated whether exosomes in a denervated hippocampal niche may affect neurogenesis. Using the FFT rat model, we extracted hippocampal exosomes and identified them using western blots, transmission electron microscopy (TEM), and nanoparticle size measurement. We also used RNA sequencing and bioinformatic analysis of exosomes to identify noncoding RNA expression profiles and neurogenesis-related miRNAs, respectively. RNA sequencing analysis demonstrated 9 upregulated and 15 downregulated miRNAs. miR-3559-3P and miR-6324 increased gradually after FFT. Thus, we investigated the function of miR-3559-3P and miR-6324 with NSC proliferation and differentiation assays. Transfection of miR-3559-3p and miR-6324 mimics inhibited the proliferation of NSCs and promoted the differentiation of NSCs into neurons, while miR-3559-3p and miR-6324 inhibitors promoted NSC proliferation and inhibited neuronal differentiation. Additionally, the exosome marker molecules CD9, CD63, and Alix were expressed in exosomes extracted from the hippocampal niche. Finally, TEM showed that exosomes were ∼100 nm in diameter and had a "saucer-like" bilayer membrane structure. Taken together, these findings suggest that differentially expressed exosomes and their related miRNAs in the denervated hippocampal niche can promote differentiation of NSCs into neurons.

GAS5 which is regulated by Lhx8 promotes the recovery of learning and memory in rats with cholinergic nerve injury.

Damage to the cholinergic system in central nervous system injuries such as traumatic brain injury (TBI) and neurodegenerative diseases leads to impaired learning and cognition. Neural stem cells (NSCs) have self-renewal capacity and multi-directional differentiation potential and considered the best source of cells for cell replacement therapy. However, how to promote the differentiation of NSCs into neurons is a major challenge in current research. Lhx8 has a specific effect on the development of the cholinergic nervous system, but its exact function is unclear. In this study, we found that Lhx8 could regulate the expression of Growth arrest-specific (GAS)5 which has been implicated in cancer but was less studied in the nervous system. Additionally, results from PCR, fluorescence in situ hybridization, and immunocytochemical analyses showed that GAS5 is mainly expressed in the cytoplasm of hippocampal neural stems cells and promotes their differentiation into neurons; the Morris water maze test demonstrated that GAS5 overexpression restored learning and memory in rats with cholinergic injury. These findings indicate that GAS5, which is regulated by Lhx8, improve brain function following cholinergic nerve injury.

MiR-210-3p Inhibits Proliferation and Migration of C6 Cells by Targeting Iscu.

Glioma is the most common primary brain tumor and the most malignant type of glioma is glioblastoma with the character of high mortality, high recurrence rate and poor prognosis. MicroRNAs act as an important component in glioma development and thus may be a potential target for the treatment of glioma. There were some researches indicated that miR-210-3p played a role in glioma development, but if it can inhibit glioma growth, as well as the underlying mechanism, is still uncertain. In the present study, we investigated the effects of miR-210-3p and its potential target gene Iscu on glioma (C6) cells proliferation and migration in vitro as well as the influence of miR-210-3p on glioma growth in vivo. The results showed that miR-210-3p inhibited the proliferation and migration of C6 cells by regulating the expression of its target gene Iscu in vitro. We also demonstrated that glioma growth was suppressed in immunodeficient mice when they were implanted with C6 cells overexpressing miR-210-3p. Our data indicated that miR-210-3p played an important role in the prevention of glioma growth by targeting Iscu and so miR-210-3p/Iscu axis might be a potential target for the treatment of glioma.

Runx1t1 promotes the neuronal differentiation in rat hippocampus.

BACKGROUND: Runt-related transcription factor 1 translocated to 1 (Runx1t1) is one of the members of the myeloid translocation gene family. Our previous work showed that Runx1t1 induced the neuronal differentiation of radial glia cells in vitro. METHODS: To better uncover the role of Runx1t1 in hippocampal neurogenesis, in this study, we further explore its localization and function during the hippocampal neurogenesis. RESULTS: Our results showed that insufficient expression of Runx1t1 reduced the neuronal differentiation, and overexpression of Runx1t1 promoted the neuronal differentiation in vitro. We also found that Runx1t1 localized in neurons but not astrocytes both in vivo and in vitro. Furthermore, we found that Runx1t1 overexpression elevated the number of newborn neurons in the hippocampal dentate gyrus. CONCLUSIONS: Taken together, our results further proved that Runx1t1 could be worked as a regulator in the process of hippocampal neurogenesis.

CXCL12 promotes proliferation of radial glia like cells after traumatic brain injury in rats.

To investigate the effect of CXCL12 on regeneration of radial glia like cells after traumatic brain injury (TBI). We randomly divided 48 rats into 4 groups: (1) the sham group, rats were performed craniotomy only, (2) the control group, saline were injected into the ipsilateral cortex after TBI, (3) the CXCL12 group, CXCL12 were injected, and (4) the CXCL12 + AMD3100 group, a mixture of CXCL12 and AMD3100 were injected. Seven days after TBI, the brain tissues were subjected to immunofluorescence double-labeled staining of BrdU/Nestin, BLBP/Nestin, BLBP/Vimentin, BLBP/SOX2, BLBP/CXCR4, BLBP/DCX. Western Blot assay was used to measure the levels of Nestin, BLBP, and Vimentin. Compared with the control group, CXCL12 treatment significantly increased the number of cells stained with BrdU/Nestin, BLBP/Nestin, and BLBP/Vimentin around the injured cortex and corpus callosum areas. CXCL12 + AMD3100 treatment significantly decreased the number of these cells compared with the CXCL12 treatment and control group. The protein levels of Nestin, BLBP, and Vimentin had the same change trends as those of the immunofluorescence staining. The BLBP/Vimentin positive cells presented with the astrocyte pattern around the injured cortex area but with the RGCs pattern around the injured corpus callosum area. The BLBP positive cells also expressed CXCR4 and SOX2. Altogether, CXCL12 promotes the proliferation of neural precursor cells after TBI by combing to its receptor, CXCR4. The proliferating neural precursor cells presents radial glial cell like cells. The RGCs-like cells can differentiate into immature neurons and promote the migration of immature neurons.

Gene expression changes induced by valproate in the process of rat hippocampal neural stem cells differentiation.

Valproate (VPA), an effective clinical approved anti-epileptic drug and mood stabilizer, has been believed to induce neuronal differentiation at the expense of inhibiting astrocytic and oligodendrocytic differentiation. Nevertheless, the involving mechanisms of it remain unclear yet. In the present study, we explored the global gene expression changes of fetus rat hippocampal neural stem cells following VPA treatment by high-throughput microarray. We obtained 874 significantly upregulated genes and 258 obviously downregulated genes (fold change > 2 and P < 0.05). Then, we performed gene ontology and pathway analyses of these differentially expressed genes and chose several genes associated with nervous system according to gene ontology analysis to conduct expression analysis to validate the reliability of the array results as well as reveal possible mechanisms of VPA. To get a better comprehension of the differentially regulated genes by VPA, we conducted protein-protein association analysis of these genes, which offered a source for further studies. In addition, we made the overlap between the VPA-downregulated genes and the predicted target genes of VPA-upregulated microRNAs (miRNAs), which were previously demonstrated. These overlapped genes may provide a source to find functional VPA/miRNA/mRNA axes during neuronal differentiation. This study first constructed a comprehensive potential downstream gene map of VPA in the process of neuronal differentiation.

Molecular Analysis of UV-C Induced Resveratrol Accumulation in Polygonum cuspidatum Leaves.

Resveratrol is one of the most studied plant secondary metabolites owing to its numerous health benefits. It is accumulated in some plants following biotic and abiotic stress pressures, including UV-C irradiation. Polygonum cuspidatum represents the major natural source of concentrated resveratrol but the underlying mechanisms as well as the effects of UV-C irradiation on resveratrol content have not yet been documented. Herein, we found that UV-C irradiation significantly increased by 2.6-fold and 1.6-fold the resveratrol content in irradiated leaf samples followed by a dark incubation for 6 h and 12 h, respectively, compared to the untreated samples. De novo transcriptome sequencing and assembly resulted into 165,013 unigenes with 98 unigenes mapped to the resveratrol biosynthetic pathway. Differential expression analysis showed that P. cuspidatum strongly induced the genes directly involved in the resveratrol synthesis, including phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase, 4-coumarate-CoA ligase and stilbene synthase (STS) genes, while strongly decreased the chalcone synthase (CHS) genes after exposure to UV-C. Since CHS and STS share the same substrate, P. cuspidatum tends to preferentially divert the substrate to the resveratrol synthesis pathway under UV-C treatment. We identified several members of the MYB, bHLH and ERF families as potential regulators of the resveratrol biosynthesis genes.

Function and mechanism of long non-coding RNA Gm21284 in the development of hippocampal cholinergic neurons.

BACKGROUND: Increasing evidence has revealed that long non-coding RNAs (lncRNAs) play a pivotal role in the development of nervous system. Our previous studies have demonstrated that enhanced cholinergic neurogenesis occurs in the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG) after cholinergic denervation, which is closely associated with the core transcription factor Lhx8. This study aimed to identify novel lncRNAs in a denervated hippocampal niche, which may affect cholinergic neurogenesis, and to explore the molecular mechanisms underlying cholinergic neurogenesis. METHODS: The gene expression profiles of the denervated hippocampus were examined by microarray analysis, and targeted lncRNAs were filtered using bioinformatics analysis. The lncRNA Gm21284 was predicted to be associated with Lhx8. RT-PCR and FISH were used to observe the expression and localization of Gm21284 in vitro and in vivo. The interaction between Gm21284 and Lhx8 and miR-30e-3P was verified using the luciferase reporter gene assay. Cell proliferation and differentiation was observed to reveal the effects of Gm21284 in cholinergic neurogenesis. RESULTS: Microarray analysis demonstrated 482 up-regulated and 135 down-regulated mRNAs, 125 up-regulated and 55 down-regulated lncRNAs, and 10 up-regulated and 3 down-regulated miRNAs in the denervated hippocampal niche. Overall, 32 lncRNAs were differentially expressed in the denervated hippocampal niche, which could interact with miR-30e-3p, miR-431, and miR-147. Among these 32 lncRNAs, Gm21284 and Adarb1 were identified after interleaving with lncRNAs in a co-expression network and WGCNA. Gm21284 was mainly located in the hippocampal DG. Furthermore, Gm21284-positive cells were considerably increased in the denervated hippocampus than in the normal side. EdU proliferation assay revealed that the proliferation of neural stem cells was repressed after the overexpression of Gm21284. Compared with the control group, the proportion of ChAT-positive cells increased at 7 days of differentiation of NSCs overexpressing Gm21284. CONCLUSION: Thus, Gm21284 functions as a competing endogenous RNA, which inhibits the proliferation of hippocampal NSCs and promotes their differentiation toward cholinergic neurons by inhibiting miR-30e-3P competitively.