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@#Introduction: Prediction and identification of miRNAs target genes are crucial for understanding the biology of miRNAs. Amidst reported long-coding RNA (lncRNA), the microRNA 195-497 cluster host gene (MIR497HG) regulation is mediated by multiple non-coding RNAs (ncRNAs) such as microRNAs (miRNAs). MIR497HG has been implicated as a tumour suppressor in various cancers. However, the impact of MIR497HG and its derived miRNAs is largely unknown and still needs to be further explored. Employing an experimental approach is often challenging since some lncRNAs are difficult to identify and isolate by the current isolation technique. Thus, bioinformatic tools are introduced to aid these problems. This study sought to search and identify the miRNAs targeting the 3’untranslated region (3’UTR) of MIR497HG. Methods: Here, bioinformatic tools were adopted to identify a unique list of miRNAs that potentially target the 3’UTR of MIR497HG. Results: A total of 57 candidate miRNAs that target the 3’UTR of MIR497HG were extracted using the miRDB. Meanwhile, STarMir predicted 291 miRNAs that potentially target the 3’UTR of MIR497HG. A common list of 36 miRNAs was obtained using the Venny 2.1.0 and further narrowed down using the LogitProb score of StarMir. Finally, a total 4 miRNAs (hsa-miR-3182, hsa-miR-7156-5p, hsa-miR-452-3p and hsa-miR-2117) were identified. The mRNA target of identified miRNAs was identified by TargetScan. Finally, Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of mRNA target was done using Enrichr. Conclusion: This finding could be useful in understanding the complex interaction between MIR497HG and its regulatory miRNA. In addition, a comparative analysis of computational miRNA-target predictions is provided in this study would potentially lay the foundations for miRNAs to be used for biomarkers in cancer research.
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This article discusses on the natural compounds from the ant plant (Myrmecodia species, family: Rubiaceae). The ethyl acetate (EtOAc) extract from the tuber of M. platytyrea was fractionated by using medium pressure liquid chromatography, giving eight fractions (F1-F8). Those fractions were evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Fraction F5 was recorded as potent (EC50 = 21.57 ± 1.40 µg/mL). Then, it was purified by using column chromatography (CC) (mobile phase = chloroform: EtOAc). From the CC, ten fractions (F5F1-F5F10) were obtained and compound (1) was isolated from F5F3 via preparative thin layer chromatography (TLC). After spraying with anisaldehyde-sulphuric reagent, compound (1) gave a green TLC spot (Rf = 0.65, 100% CHCl3 , multiple development). The 1 H-Nuclear Magnetic Resonance (NMR) spectroscopy (500 MHz, CDCl3 ) was performed to determine the chemical framework of (1). This compound was identified as morindolide, having an iridoid structure. Meanwhile, the mass spectra for compounds (2) and (3) were analysed. The data presented the molecular ion at m/z 375 [M-H]- and 255, suggesting the formulation of 2-(2-methylbutyryl)phloroglucinol glucoside and a flavanone, respectively. From the literature, compound (1) was firstly isolated from a Chinese natural medicine, the dried root of Morinda officinalis (family: Rubiaceae). The flavonoids are also included as the biologically active compounds from Myrmecodia. In short, this is the first occurrence of morindolide from the ant plant.