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To investigate the role and mechanism of microRNA-124-3p (miR-124-3p) and serine palmitoyltransferase long chain base subunit 2 (SPTLC2) in neuronal apoptosis induced by mechanical injury. Transient transfection was used to modify the expression of miR-124-3p and SPTLC2. After transfection, neuronal apoptosis was evaluated in an in vitro injury model of primary neurons using TUNEL staining and western blot. The correlation between miR-124-3p and SPTLC2 was identified through a dual luciferase reporter assay in HEK293 cells. A rescue experiment in primary neurons was performed to further confirm the result. To explore the downstream mechanisms, co-immunoprecipitation was performed to identify proteins that interact with SPTLC2 in toll-like receptor 4 (TLR4) signalling pathway. Subsequently, the relative expression levels of TLR4 pathway molecules were measured by western blot. Our results showed that increased miR-124-3p can inhibit neuronal apoptosis, which is opposite to the effect of SPTLC2. In addition, miR-124-3p was proved to negatively regulate SPTLC2 expression and suppress the apoptosis-promoting effect of SPTLC2 via the TLR4 signalling pathway.
相似文献Trigeminal neuralgia (TN) is a type of chronic neuropathic pain that is caused by peripheral nerve lesions that result from various conditions, including the compression of vessels, tumors and viral infections. MicroRNAs (miRs) are increasingly recognized as potential regulators of neuropathic pain. Previous evidence has demonstrated that miR-195 is involved in neuropathic pain, but the mechanism remains unclear. To investigate the pathophysiological role of miR-195 and Shh signaling in TN, persistent facial pain was induced by infraorbital nerve chronic constriction injury (CCI-IoN), and facial pain responses were evaluated by Von Frey hairs. qPCR and Western blotting were used to determine the relative expression of miR-195 and Patched1, the major receptor of the Sonic Hedgehog (Shh) signaling pathway, in the caudal brain stem at distinct time points after CCI-IoN. Here, we found that the expression of miR-195 was increased in a rat model of CCI-IoN. In contrast, the expression of Patched1 decreased significantly. Luciferase assays confirmed the binding of miR-195 to Patched1. In addition, the overexpression of miR-195 by an intracerebroventricular (i.c.v) administration of LV-miR-195 aggravated facial pain development, and this was reversed by upregulating the expression of Patched1. These results suggest that miR-195 is involved in the development of TN by targeting Patched1 in the Shh signaling pathway, thus regulating extracellular glutamate.
相似文献Methods. Examination of the type material confirmed that the alar cell structure in these species do not conform to the generic concept of Heterophyllium (Schimp.) Kindb. The study also revealed some new features previously unreported in these species, i.e., the filamentous pseudoparaphyllia, one of the characteristic features of the genus Isopterygium Mitt.
Key Results & Conclusions. Three new combinations, Isopterygium albicans (Thér.) Y.Jia & S.He, I. micro-alare (Broth. & Paris) Y.Jia & S.He, and I. tonkinense (Broth. & Paris) Y.Jia & S.He are proposed. Heterophyllium henryi Tixier is treated as a new synonym of Brotherella henonii (Duby) M.Fleisch. 相似文献
The Taiyi mountainous region of Shandong province in eastern China has an abundance of wild Malus species. We evaluated the genetic diversity of 88 Malus accessions (45 Asian apple cultivars, 10 American apple cultivars, 12 European apple cultivars, 19 Chinese wild apples, and two apple cultivars with unknown origins) based on single-nucleotide polymorphism (SNP) markers. A total of 38,364 SNPs were obtained with an average of 2256 SNPs per chromosome. The average of the polymorphism information content (PIC), gene diversity, and allele frequency for SNPs was 0.268, 0.306, and 0.364, respectively. A circular phylogenetic tree constructed based on SNP data revealed that the 88 Malus accessions could be divided into three groups. However, a population structure analysis suggested the 88 Malus accessions could be divided into four groups. A principal component analysis (PCA) revealed some population stratification. The first three PCs accounted for 41.62% of the population-wide SNP variation, with PC1 accounting for 33.9%. Moreover, the kinship values of the 88 Malus accessions ranged from 0 to 2.36, with 96.42% of the kinship values between 0 and 0.2. A phylogenetic tree and a PCA indicated the Chinese wild apples widely distributed among the cultivated apples had a diverse genetic background. Characterizing the genetic relationships between cultivated apples and Chinese wild apples is essential for increasing the genetic diversity of the germplasms used by apple breeders.
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