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Alzheimer's disease (AD) is currently the most common neurodegenerative disease. Glycogen synthase kinase 3β (GSK-3β) is a pivotal factor in AD pathogenesis. Recent research has demonstrated that plant miRNAs exert cross-kingdom regulation on the target genes in animals. Gastrodia elata ( G. elata ) is a valuable traditional Chinese medicine that has significant pharmacological activity against diseases of the central nervous system (CNS). Our previous studies have indicated that G. elata -specific miRNA plays a cross-kingdom regulatory role for the NF- κ B signaling pathway in mice. In this study, further bioinformatics analysis suggested that Gas-miR36-5p targets GSK-3β. Through western blot, RT-qPCR, and assessments of T-AOC, SOD, and MDA levels, Gas-miR36-5p demonstrated its neuroprotective effects in an AD cell model. Furthermore, Gas-miR36-5p was detected in the murine brain tissues. The results of the Morris water maze test and western blot analysis provided positive evidence for reversing the learning deficits and hyperphosphorylation of Tau in AD mice, elucidating significant neuroprotective effects in an AD model following G. elata RNA administration. Our research emphasizes Gas-miR36-5p as a novel G. elata -specific miRNA with neuroprotective properties in Alzheimer's disease by targeting GSK-3β. Consequently, our findings provide valuable insights into the cross-kingdom regulatory mechanisms underlying G. elata -specific miRNA, presenting a novel perspective for the treatment of Alzheimer's disease.

MicroRNA is an important regulation factor in insect development and metamorphosis. It has been reported that E(spl)m4 is a miRNA-targeted gene, as well as the target of the Notch signaling pathway in Drosophila. The expression of E(spl)m4 can be regulated by microRNA and further affect the neural development of Drosophila. Here, we found that BmEm4, an ortholog of E(spl)m4 from Bombyx mori, was the target gene of bmo-miR-79, with target sites containing the Brd and K boxes of the BmEm4_3'UTR, which was validated by the dual luciferase reporter (DLR) assay. Furthermore, bmo-miR-79 mimics can inhibit the expression of BmEm4 in BmN cells after transfection, and bmo-miR-79 can also inhibit the expression of BmEm4 in different developmental stages of Bombyx mori at a posttranscriptional level, to different degrees. The EMSA test further showed that bmo-miR-79 could bind to BmAGO2, which is the Bombyx mori argonaute2 protein, suggesting that bmo-miR-79 might regulate the expression of BmEm4 by forming miRISC complexes with BmAGO2. Taken together, bmo-miR-79 could regulate the expression of BmEm4 mediated by BmAGO2 and further affect its function in the silkworm Bombyx mori., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Dysregulation of miR-452 has been observed in many tumors, but its biological function in hepatocellular carcinoma (HCC) is still unknown. Our results showed that miR-452 expression is significantly increased in HCC tissues and HCC cell lines. We also found that overexpression of miR-452 dramatically accelerated proliferation, induced cell cycle from G1 to S transition, and blocked apoptosis of HCC cells. Migration and matrigel invasion assays indicated that miR-452 significantly promotes HepG2 and QGY-7703 cells migration and invasion in vitro. Further studies showed that miR-452 directly targets the 3'-untranslated region of cyclin-dependent kinase inhibitor 1B (CDKN1B), ectopic miR-452 expression suppressed CDKN1B expression on mRNA and protein level. Silencing CDKN1B by small interfering RNA resembled the phenotype resulting from ectopic miR-452 expression. This study provides new insights into the potential molecular mechanisms that miRNA-452 contributed to HCC.

MicroRNAs are indispensable players in the regulation of a broad range of biological processes. Here, we report the first deep sequencing of the whitespotted bamboo shark (Chiloscyllium plagiosum) liver. We mapped 91 miRNAs in the Callorhinchus milii genome that have previously been described in the Danio rerio, Fugu rubripes, Oryzias latipes, Xenopus laevis, Xenopus tropicalis, Homo sapiens, and Mus musculus. In addition, 156 new putative candidate (PC) C. plagiosum miRNAs were identified. From these 247 miRNAs, 39 miRNA clusters were identified, and the expression of these clustered miRNAs was observed to vary significantly. A total of 7 candidate miRNAs were selected for expression confirmation by stem-loop RT-PCR. This study resulted in the addition of a significant number of novel miRNA sequences to GenBank and laid the foundation for further understanding of the function of miRNAs in the regulation of C. plagiosum liver development., (Copyright © 2013 Elsevier B.V. All rights reserved.)

To understand the mechanisms of liver regeneration better to promote research examining liver diseases and marine biology, normal and regenerative liver tissues of Chiloscyllium plagiosum were harvested 0 h and 24 h after partial hepatectomy (PH) and used to isolate small RNAs for miRNA sequencing. In total, 91 known miRNAs and 166 putative candidate (PC) miRNAs were identified for the first time in Chiloscyllium plagiosum. Through target prediction and GO analysis, 46 of 91 known miRNAs were screened specially for cellular proliferation and growth. Differential expression levels of three miRNAs (xtr-miR-125b, fru-miR-204, and hsa-miR-142-3p_R-1) related to cellular proliferation and apoptosis were measured in normal and regenerating liver tissues at 0 h, 6 h, 12 h, and 24 h using real-time PCR. The expression of these miRNAs showed a rising trend in regenerative liver tissues at 6 h and 12 h but exhibited a downward trend compared to normal levels at 24 h. Differentially expressed genes were screened in normal and regenerating liver tissues at 24 h by DDRT-PCR, and ten sequences were identified. This study provided information regarding the function of genes related to liver regeneration, deepened the understanding of mechanisms of liver regeneration, and resulted in the addition of a significant number of novel miRNAs sequences to GenBank.

MicroRNAs (miRNAs) are the family of noncoding single-strand RNA molecules of 21-25 nucleotides in length and play a broad and key regulation role in various physiological and pathological processes including differentiation, apoptosis, proliferation, and tumorigenesis. In Bombyx mori, a total of 487 pre-miRNAs and 562 mature miRNAs were identified by experimental or computational approaches, but their functions remain unknown. To carry out the research of gain-of-function of miRNAs in BmN cells, we firstly identified the endogenous expression of miRNAs in BmN cells by microarray and found that only 73 miRNAs could be detected by miRNA microarray. Then three low abundance or undetected miRNAs, pri-mir-1a, pri-mir-8 and pri-mir-133, were selected to express in BmN cells. The eukaryotic expression vector pIEx-1 harboring baculovirus ie1 promoter and hr5 enhancer was screened and used for expressing miRNA in BmN cells. Three miRNA expression vectors pIEx-1-EGFP-pri-mir-1a/8/133 were constructed, which contained the three corresponding pri-miRNA sequences, respectively. The constructed miRNA vectors were successfully transfected into BmN cells and the qRT-PCR analysis showed that relative abundance of bmo-mir-1a, bmo-mir-8 and bmo-mir-133 in BmN cells transfected with the pIEx-1-EGFP-pri-mir-1a/8/133 is as 32, 4.4 and 904 times as that in BmN cells transfected with the control vector pIEx-1-EGFP, respectively. The present work lays a foundation for the further functional studies of miRNAs in silkworm., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression by targeting messenger RNAs (mRNAs) and causing mRNA cleavage or translation blockage. Of the 355 Arthropod miRNAs that have been identified, only 21 are B. mori miRNAs that were predicted computationally; of these, only let-7 has been confirmed by Northern blotting., Results: Combining a computational method based on sequence homology searches with experimental identification based on microarray assays and Northern blotting, we identified 46 miRNAs, an additional 21 plausible miRNAs, and a novel small RNA in B. mori. The latter, bmo-miR-100-like, was identified using the known miRNA aga-miR-100 as a probe; bmo-miR-100-like was detected by microarray assay and Northern blotting, but its precursor sequences did not fold into a hairpin structure. Among these identified miRNAs, we found 12 pairs of miRNAs and miRNA*s. Northern blotting revealed that some B. mori miRNA genes were expressed only during specific stages, indicating that B. mori miRNA genes (e.g., bmo-miR-277) have developmentally regulated patterns of expression. We identified two miRNA gene clusters in the B. mori genome. bmo-miR-2b, which is found in the gene cluster bmo-miR-2a-1/bmo-miR-2a-1*/bmo-miR-2a-2/bmo-miR-2b/bmo-miR-13a*/bmo-miR-13b, encodes a newly identified member of the mir-2 family. Moreover, we found that methylation can increase the sensitivity of a DNA probe used to detect a miRNA by Northern blotting. Functional analysis revealed that 11 miRNAs may regulate 13 B. mori orthologs of the 25 known Drosophila miRNA-targeted genes according to the functional conservation. We predicted the binding sites on the 1671 3'UTR of B. mori genes; 547 targeted genes, including 986 target sites, were predicted. Of these target sites, 338 had perfect base pairing to the seed region of 43 miRNAs. From the predicted genes, 61 genes, each of them with multiple predicted target sites, should be considered excellent candidates for future functional studies. Biological classification of predicted miRNA targets showed that "binding", "catalytic activity" and "physiological process" were over-represented for the predicted genes., Conclusion: Combining computational predictions with microarray assays, we identified 46 B. mori miRNAs, 13 of which were miRNA*s. We identified a novel small RNA and 21 plausible B. mori miRNAs that could not be located in the available B. mori genome, but which could be detected by microarray. Thirteen and 547 target genes were predicted according to the functional conservation and binding sites, respectively. Identification of miRNAs in B. mori, particularly those that are developmentally regulated, provides a foundation for subsequent functional studies.