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Methods in Molecular Biology (Clifton,... 2014In animals, the Microprocessor complex cleaves primary transcripts of microRNAs (pri-miRNAs) to produce precursor microRNAs in the nucleus. The core components of...
In animals, the Microprocessor complex cleaves primary transcripts of microRNAs (pri-miRNAs) to produce precursor microRNAs in the nucleus. The core components of Microprocessor include the Drosha ribonuclease and its RNA-binding partner protein DiGeorge critical region 8 (DGCR8). DGCR8 has been shown to tightly bind an Fe(III) heme cofactor, which activates its pri-miRNA processing activity. Here we describe how to reconstitute pri-miRNA processing using recombinant human Drosha and DGCR8 proteins. In particular, we present the procedures for expressing and purifying DGCR8 as an Fe(III) heme-bound dimer, the most active form of this protein, and for estimating its heme content.
Topics: Escherichia coli; Heme; Humans; MicroRNAs; Proteins; RNA Cleavage; RNA Processing, Post-Transcriptional; RNA, Messenger; RNA-Binding Proteins; Recombinant Proteins; Ribonuclease III; Transcription, Genetic
PubMed: 24166303
DOI: 10.1007/978-1-62703-703-7_5 -
Zhurnal Nevrologii I Psikhiatrii Imeni... 2018Today, stroke is the third most common pathology after cardiovascular disease and cancer, as well as the leading cause of disability in the world. Although some progress... (Review)
Review
Today, stroke is the third most common pathology after cardiovascular disease and cancer, as well as the leading cause of disability in the world. Although some progress has been made in the field of primary and secondary stroke prevention over the past few decades, a deeper knowledge of the pathophysiology of the disease is needed to significantly improve diagnosis and therapy. MicroRNA (miRNA) is an important, recently identified class of posttranscriptional regulators of gene expression. MiRNA can be used as a tool for therapeutic interventions. This review considers a role of miRNAs in the regulation of experimental stroke and in the development of carotid artery stroke. A potential role of miRNAs as promising biomarkers of stroke is discussed.
Topics: Biomarkers; Brain Ischemia; Carotid Arteries; Humans; MicroRNAs; Stroke
PubMed: 29798981
DOI: 10.17116/jnevro20181183248-56 -
RNA (New York, N.Y.) Jan 2020Within the forensic science community, there is a continued push to develop novel tools to aid in criminal investigations. microRNA (miRNA) analysis has been the focus... (Review)
Review
Within the forensic science community, there is a continued push to develop novel tools to aid in criminal investigations. microRNA (miRNA) analysis has been the focus of many researcher's attention in the biomedical field since its discovery in 1993; however, the forensic application of miRNA analysis has only been suggested within the last 10 years and has been gaining considerable traction recently. The primary focus of the forensic application of miRNA analysis has been on body fluid identification to provide confirmatory universal analysis of unknown biological stains obtained from crime scenes or evidence items. There are, however, other forensic applications of miRNA profiling that have shown potential, yet are largely understudied, and warrant further investigation such as organ tissue identification, donor age estimation, and more. This review paper aims to evaluate the current literature and future potential of miRNA analysis within the forensic science field.
Topics: Forensic Anthropology; Forensic Medicine; Forensic Sciences; Humans; MicroRNAs
PubMed: 31658993
DOI: 10.1261/rna.072173.119 -
Frontiers in Bioscience (Landmark... Nov 2023Fibrotic disorders are defined by accumulating excessive extracellular matrix (ECM) components, especially collagens, in various organs, leading to tissue scarring and... (Review)
Review
Fibrotic disorders are defined by accumulating excessive extracellular matrix (ECM) components, especially collagens, in various organs, leading to tissue scarring and organ dysfunction. These conditions are associated with significant challenges in the healthcare system because of their progressive nature and limited treatment options. MicroRNAs (miRNAs) are small non-coding RNA molecules (approximately 22 nucleotides) that modulate gene expression by selectively targeting mRNAs for degradation or translational repression. MiRNAs have recently been identified as potential targets for therapeutic developments in fibrotic disorders. They play vital roles in inducing fibrotic phenotype by regulating fibroblast activation and ECM remodeling. Multiple strategies for targeting specific miRNAs in fibrotic disorders have been explored, including antisense oligonucleotides, small molecule modulators, and natural compounds. This review discussed the role of miRNAs in different fibrotic disorders, including cardiac fibrosis, liver fibrosis, kidney fibrosis, lung fibrosis, dermal fibrosis, and primary myelofibrosis, with recent advances in developing miRNA-based therapeutics.
Topics: Humans; MicroRNAs; Fibrosis; Pulmonary Fibrosis; Liver Cirrhosis; Oligonucleotides, Antisense
PubMed: 38062842
DOI: 10.31083/j.fbl2811317 -
Nucleic Acids Research Jun 2018Microprocessor, which consists of a ribonuclease III DROSHA and its cofactor DGCR8, initiates microRNA (miRNA) maturation by cleaving primary miRNA transcripts...
Microprocessor, which consists of a ribonuclease III DROSHA and its cofactor DGCR8, initiates microRNA (miRNA) maturation by cleaving primary miRNA transcripts (pri-miRNAs). We recently demonstrated that the DGCR8 dimer recognizes the apical elements of pri-miRNAs, including the UGU motif, to accurately locate and orient Microprocessor on pri-miRNAs. However, the mechanism underlying the selective RNA binding remains unknown. In this study, we find that hemin, a ferric ion-containing porphyrin, enhances the specific interaction between the apical UGU motif and the DGCR8 dimer, allowing Microprocessor to achieve high efficiency and fidelity of pri-miRNA processing in vitro. Furthermore, by generating a DGCR8 mutant cell line and carrying out rescue experiments, we discover that hemin preferentially stimulates the expression of miRNAs possessing the UGU motif, thereby conferring differential regulation of miRNA maturation. Our findings reveal the molecular action mechanism of hemin in pri-miRNA processing and establish a novel function of hemin in inducing specific RNA-protein interaction.
Topics: Cell Line; Gene Knockout Techniques; Hemin; Humans; MicroRNAs; RNA Precursors; RNA-Binding Proteins; Ribonuclease III
PubMed: 29750274
DOI: 10.1093/nar/gky248 -
General and Comparative Endocrinology Sep 2020The sesquiterpenoid juvenile hormone(s) (JHs) of insects are the primary regulators of growth, metamorphosis, and reproduction in most insect species. As a consequence,... (Review)
Review
The sesquiterpenoid juvenile hormone(s) (JHs) of insects are the primary regulators of growth, metamorphosis, and reproduction in most insect species. As a consequence, it is essential that JH production be precisely regulated so that it is present only during appropriate periods necessary for the control of these processes. The presence of JH at inappropriate times results in disruption to metamorphosis and development and, in some cases, to disturbances in female reproduction. Neuropeptides regulate the timing and production of JH by the corpora allata. Allatostatin and allatotropin were the names coined for neuropeptides that serve as inhibitors or stimulators of JH biosynthesis, respectively. Three different allatostatin neuropeptide families are capable of inhibiting juvenile hormone but only one family is utilized for that purpose dependent on the insect studied. The function of allatotropin also varies in different insects. These neuropeptides are pleiotropic in function acting on diverse physiological processes in different insects such as muscle contraction, sleep and neuromodulation. Genome projects and expression studies have assigned individual neuropeptide families to their respective receptors. An understanding of the localization of these receptors is providing clues as to how numerous peptide families might be integrated in regulating physiological functions. In recent years microRNAs have been identified that down-regulate enzymes and transcription factors that are involved in the biosynthesis and action of juvenile hormone.
Topics: Amino Acid Sequence; Animals; Evolution, Molecular; Insect Hormones; Juvenile Hormones; MicroRNAs; Neuropeptides
PubMed: 32413346
DOI: 10.1016/j.ygcen.2020.113507 -
Molecular Cell May 2020Metazoan microRNAs require specific maturation steps initiated by Microprocessor, comprising Drosha and DGCR8. Lack of structural information for the assembled complex...
Metazoan microRNAs require specific maturation steps initiated by Microprocessor, comprising Drosha and DGCR8. Lack of structural information for the assembled complex has hindered an understanding of how Microprocessor recognizes primary microRNA transcripts (pri-miRNAs). Here we present a cryoelectron microscopy structure of human Microprocessor with a pri-miRNA docked in the active site, poised for cleavage. The basal junction is recognized by a four-way intramolecular junction in Drosha, triggered by the Belt and Wedge regions that clamp over the ssRNA. The belt is important for efficiency and accuracy of pri-miRNA processing. Two dsRBDs form a molecular ruler to measure the stem length between the two dsRNA-ssRNA junctions. The specific organization of the dsRBDs near the apical junction is independent of Drosha core domains, as observed in a second structure in the partially docked state. Collectively, we derive a molecular model to explain how Microprocessor recognizes a pri-miRNA and accurately identifies the cleavage site.
Topics: Cryoelectron Microscopy; Humans; MicroRNAs; Models, Molecular; Protein Conformation; RNA, Double-Stranded; RNA-Binding Proteins; Ribonuclease III
PubMed: 32220646
DOI: 10.1016/j.molcel.2020.02.016 -
Molecular Neurobiology May 2017Fragile X mental retardation protein (FMRP), associated with fragile X syndrome, is known as an RNA-binding protein to regulate gene expression at post-transcriptional...
Fragile X mental retardation protein (FMRP), associated with fragile X syndrome, is known as an RNA-binding protein to regulate gene expression at post-transcriptional level in the brain. FMRP is also involved in microRNA (miRNA) biogenesis during the process of precursor miRNA (pre-miRNA) into mature miRNA. However, there is no description of the effect of FMRP on primary miRNA (pri-miRNA) processing. Here, we uncover a novel role of FMRP in pri-miRNA processing via controlling Drosha translation. We show that the expression of DROSHA protein, instead of its messenger RNA (mRNA) transcripts, is downregulated in both the hippocampus of Fmr1-knockout mice and the FMRP-knockdown Neuro-2a cells. Overexpression or knockdown FMRP does not alter Drosha mRNA stability. Immunoprecipitation and polysome analyses demonstrate that FMRP binds to the Drosha mRNA and enhances its translation. Additionally, we show that loss of FMRP in Fmr1-deficient mice results in the accumulation of three in six analyzed pri-miRNAs and the reduction of the corresponding pre-miRNAs and mature miRNAs. Thus, our data suggest that FMRP is involved in pri-miRNA processing via enhancing DROSHA expression that may play an important role in fragile X syndrome.
Topics: Animals; Cell Line, Tumor; Down-Regulation; Fragile X Mental Retardation Protein; Gene Knockdown Techniques; Mice, Knockout; MicroRNAs; Protein Binding; Protein Biosynthesis; RNA Processing, Post-Transcriptional; RNA Stability; RNA, Messenger; Ribonuclease III; Up-Regulation
PubMed: 26993298
DOI: 10.1007/s12035-016-9855-9 -
The EMBO Journal Jan 2005A critical step during human microRNA maturation is the processing of the primary microRNA transcript by the nuclear RNaseIII enzyme Drosha to generate the approximately...
A critical step during human microRNA maturation is the processing of the primary microRNA transcript by the nuclear RNaseIII enzyme Drosha to generate the approximately 60-nucleotide precursor microRNA hairpin. How Drosha recognizes primary RNA substrates and selects its cleavage sites has remained a mystery, especially given that the known targets for Drosha processing show no discernable sequence homology. Here, we show that human Drosha selectively cleaves RNA hairpins bearing a large (>/=10 nucleotides) terminal loop. From the junction of the loop and the adjacent stem, Drosha then cleaves approximately two helical RNA turns into the stem to produce the precursor microRNA. Beyond the precursor microRNA cleavage sites, approximately one helix turn of stem extension is also essential for efficient processing. While the sites of Drosha cleavage are determined largely by the distance from the terminal loop, variations in stem structure and sequence around the cleavage site can fine-tune the actual cleavage sites chosen.
Topics: Animals; Base Sequence; Cell Line; Humans; MicroRNAs; Molecular Sequence Data; Nucleic Acid Conformation; RNA Precursors; Ribonuclease III
PubMed: 15565168
DOI: 10.1038/sj.emboj.7600491 -
Biomedicine & Pharmacotherapy =... Sep 2023MicroRNAs (miRNAs) are a class of small non-coding RNAs that post-transcriptionally regulate the expression of approximately 50 % of all protein-coding genes. They have... (Review)
Review
MicroRNAs (miRNAs) are a class of small non-coding RNAs that post-transcriptionally regulate the expression of approximately 50 % of all protein-coding genes. They have been demonstrated to act as key regulators in various pathophysiological processes and play significant roles in a wide range of human diseases, particularly cancer. Current research highlights the aberrant expression of microRNA-488 (miR-488) in multiple human diseases and its critical involvement in disease initiation and progression. Moreover, the expression level of miR-488 has been linked to clinicopathological features and patient prognosis across different diseases. However, a comprehensive systematic review of miR-488 is lacking. Therefore, our study aims to consolidate the current knowledge surrounding miR-488, with a primary focus on its emerging biological functions, regulatory mechanisms, and potential clinical applications in human diseases. Through this review, we aim to establish a comprehensive understanding of the diverse roles of miR-488 in the development of various diseases.
Topics: Humans; MicroRNAs; Neoplasms
PubMed: 37418982
DOI: 10.1016/j.biopha.2023.115115