scholarly journals RNA dactyloscopy

2017 ◽  
Vol 63 (4) ◽  
Author(s):  
Marta Magdalena Gabryelska ◽  
Eliza Wyszko ◽  
Jan Barciszewski

Despite the wealth of data on RNA secondary structure, conformational dynamics and tertiary structure in vitro and in vivo, predicting RNA biological activity in cellular environments remains difficult. Here we describe a method of in silico RNA fingerprinting that allows efficient design of hammerhead ribozyme molecules with a high intracellular efficiency. Our method, which we call RNA dactyloscopy, is a reliable tool for assessing catalytic properties, modeling and design of RNA.

2002 ◽  
Vol 30 (6) ◽  
pp. 1145-1149 ◽  
Author(s):  
Y. Takagi ◽  
E. Suyama ◽  
H. Kawasaki ◽  
M. Miyagishi ◽  
K. Taira

A hammerhead ribozyme was demonstrated to be a metalloenzyme. By controlling the metal-binding ability of the hammerhead ribozyme in the presence or absence of a specific sequence of interest, we engineered an allosterically controllable ribozyme, designated the maxizyme. Hybrid ribozymes were then constructed by coupling the site-specific cleavage activity of a hammerhead ribozyme with the unwinding activity of an endogenous RNA helicase. This leads to extremely efficient cleavage of target mRNA, not only in vitro, but also in vivo, and eliminates one of the major problems arising in the application of ribozymes for cleavage of mRNA in vivo: that many target sites on the RNA were previously inaccessible to cleavage owing to secondary and/or tertiary structure formation. Since hybrid ribozymes can efficiently attack target sites within mRNA, libraries were made of hybrid ribozymes with randomized binding arms, which were then introduced into cells. This procedure made it possible to readily identify the relevant genes associated with a specific phenotype, such as in apoptosis and cancer metastasis pathways. This application of a randomized library of hybrid ribozymes represents a simple, yet powerful, method for the identification of genes associated with specific phenotypes in the post-genome era. Moreover, vector-based siRNA (short-interfering RNA for RNA interference, RNAi) can also be used for the creation of the libraries and for the subsequent confirmation of the identified genes, relevant in the examined phenotype.


2013 ◽  
Vol 451 (3) ◽  
pp. 439-451 ◽  
Author(s):  
Marta Magdalena Gabryelska ◽  
Eliza Wyszko ◽  
Maciej Szymański ◽  
Mariusz Popenda ◽  
Jan Barciszewski

Hammerhead ribozyme is a versatile tool for down-regulation of gene expression in vivo. Owing to its small size and high activity, it is used as a model for RNA structure–function relationship studies. In the present paper we describe a new extended hammerhead ribozyme HH-2 with a tertiary stabilizing motif constructed on the basis of the tetraloop receptor sequence. This ribozyme is very active in living cells, but shows low activity in vitro. To understand it, we analysed tertiary structure models of substrate–ribozyme complexes. We calculated six unique catalytic core geometry parameters as distances and angles between particular atoms that we call the ribozyme fingerprint. A flanking sequence and tertiary motif change the geometry of the general base, general acid, nucleophile and leaving group. We found almost complete correlation between these parameters and the decrease of target gene expression in the cells. The tertiary structure model calculations allow us to predict ribozyme intracellular activity. Our approach could be widely adapted to characterize catalytic properties of other RNAs.


2020 ◽  
Vol 27 (1) ◽  
pp. 54-77 ◽  
Author(s):  
Bogdan Bumbăcilă ◽  
Mihai V. Putz

Pesticides are used today on a planetary-wide scale. The rising need for substances with this biological activity due to an increasing consumption of agricultural and animal products and to the development of urban areas makes the chemical industry to constantly investigate new molecules or to improve the physicochemical characteristics, increase the biological activities and improve the toxicity profiles of the already known ones. Molecular databases are increasingly accessible for in vitro and in vivo bioavailability studies. In this context, structure-activity studies, by their in silico - in cerebro methods, are used to precede in vitro and in vivo studies in plants and experimental animals because they can indicate trends by statistical methods or biological activity models expressed as mathematical equations or graphical correlations, so a direction of study can be developed or another can be abandoned, saving financial resources, time and laboratory animals. Following this line of research the present paper reviews the Structure-Activity Relationship (SAR) studies and proposes a correlation between a topological connectivity index and the biological activity or toxicity made as a result of a study performed on 11 molecules of organophosphate compounds, randomly chosen, with a basic structure including a Phosphorus atom double bounded to an Oxygen atom or to a Sulfur one and having three other simple covalent bonds with two alkoxy (-methoxy or -ethoxy) groups and to another functional group different from the alkoxy groups. The molecules were packed on a cubic structure consisting of three adjacent cubes, respecting a principle of topological efficiency, that of occupying a minimal space in that cubic structure, a method that was called the Clef Method. The central topological index selected for correlation was the Wiener index, since it was possible this way to discuss different adjacencies between the nodes in the graphs corresponding to the organophosphate compounds molecules packed on the cubic structure; accordingly, "three dimensional" variants of these connectivity indices could be considered and further used for studying the qualitative-quantitative relationships for the specific molecule-enzyme interaction complexes, including correlation between the Wiener weights (nodal specific contributions to the total Wiener index of the molecular graph) and the biochemical reactivity of some of the atoms. Finally, when passing from SAR to Q(uantitative)-SAR studies, especially by the present advanced method of the cubic molecule (Clef Method) and its good assessment of the (neuro)toxicity of the studied molecules and of their inhibitory effect on the target enzyme - acetylcholinesterase, it can be seen that a predictability of the toxicity and activity of different analogue compounds can be ensured, facilitating the in vivo experiments or improving the usage of pesticides.


2019 ◽  
Vol 16 (3) ◽  
pp. 175-180
Author(s):  
Fengjin Hao ◽  
Yueqin Feng ◽  
Yifu Guan

Objective: To verify whether the botulinum toxin heavy chain HCS has specific neuronal targeting function and to confirm whether TAT-EGFP-LC has hydrolyzable SNAP-25 and has transmembrane biological activity. Methods: We constructed the pET-28a-TAT-EGFP-HCS/LC plasmid. After the plasmid is expressed and purified, we co-cultured it with nerve cells or tumors. In addition, we used Western-Blot to identify whether protein LC and TAT-EGFP-LC can digest the protein SNAP-25. Results: Fluorescence imaging showed that PC12, BV2, C6 and HeLa cells all showed green fluorescence, and TAT-EGFP-HCS had the strongest fluorescence. Moreover, TAT-EGFP-LC can hydrolyze intracellular SNAP-25 in PC12 cells, C6 cells, BV2 cells and HeLa, whereas LC alone cannot. In addition, the in vivo protein TAT-EGFP-HCS can penetrate the blood-brain barrier and enter mouse brain tissue. Conclusion: TAT-EGFP-HSC expressed in vitro has neural guidance function and can carry large proteins across the cell membrane without influencing the biological activity.


2020 ◽  
Vol 17 (2) ◽  
pp. 125-132
Author(s):  
Marjanu Hikmah Elias ◽  
Noraziah Nordin ◽  
Nazefah Abdul Hamid

Background: Chronic Myeloid Leukaemia (CML) is associated with the BCRABL1 gene, which plays a central role in the pathogenesis of CML. Thus, it is crucial to suppress the expression of BCR-ABL1 in the treatment of CML. MicroRNA is known to be a gene expression regulator and is thus a good candidate for molecularly targeted therapy for CML. Objective: This study aims to identify the microRNAs from edible plants targeting the 3’ Untranslated Region (3’UTR) of BCR-ABL1. Methods: In this in silico analysis, the sequence of 3’UTR of BCR-ABL1 was obtained from Ensembl Genome Browser. PsRNATarget Analysis Server and MicroRNA Target Prediction (miRTar) Server were used to identify miRNAs that have binding conformity with 3’UTR of BCR-ABL1. The MiRBase database was used to validate the species of plants expressing the miRNAs. The RNAfold web server and RNA COMPOSER were used for secondary and tertiary structure prediction, respectively. Results: In silico analyses revealed that cpa-miR8154, csi-miR3952, gma-miR4414-5p, mdm-miR482c, osa-miR1858a and osa-miR1858b show binding conformity with strong molecular interaction towards 3’UTR region of BCR-ABL1. However, only cpa-miR- 8154, osa-miR-1858a and osa-miR-1858b showed good target site accessibility. Conclusion: It is predicted that these microRNAs post-transcriptionally inhibit the BCRABL1 gene and thus could be a potential molecular targeted therapy for CML. However, further studies involving in vitro, in vivo and functional analyses need to be carried out to determine the ability of these miRNAs to form the basis for targeted therapy for CML.


2021 ◽  
Vol 22 (11) ◽  
pp. 5912
Author(s):  
Patricia Alvarez-Sieiro ◽  
Hendrik R. Sikkema ◽  
Bert Poolman

Many proteins have a multimeric structure and are composed of two or more identical subunits. While this can be advantageous for the host organism, it can be a challenge when targeting specific residues in biochemical analyses. In vitro splitting and re-dimerization to circumvent this problem is a tedious process that requires stable proteins. We present an in vivo approach to transform homodimeric proteins into apparent heterodimers, which then can be purified using two-step affinity-tag purification. This opens the door to both practical applications such as smFRET to probe the conformational dynamics of homooligomeric proteins and fundamental research into the mechanism of protein multimerization, which is largely unexplored for membrane proteins. We show that expression conditions are key for the formation of heterodimers and that the order of the differential purification and reconstitution of the protein into nanodiscs is important for a functional ABC-transporter complex.


Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2198
Author(s):  
Marcos Mateo-Fernández ◽  
Fernando Valenzuela-Gómez ◽  
Rafael Font ◽  
Mercedes Del Río-Celestino ◽  
Tania Merinas-Amo ◽  
...  

Taurine is one of the main ingredients used in energy drinks which are highly consumed in adolescents for their sugary taste and stimulating effect. With energy drinks becoming a worldwide phenomenon, the biological effects of these beverages must be evaluated in order to fully comprehend the potential impact of these products on the health due to the fact nutrition is closely related to science since the population consumes food to prevent certain diseases. Therefore, the aim of this study was to evaluate the biological effects of taurine, glucose, classic Red Bull® and sugar-free Red Bull® in order to check the food safety and the nutraceutical potential of these compounds, characterising different endpoints: (i) Toxicology, antitoxicology, genotoxicology and life expectancy assays were performed in the Drosophila melanogaster model organism; (ii) The in vitro chemopreventive activity of testing compounds was determined by assessing their cytotoxicity, the proapoptotic DNA-damage capability to induce internucleosomal fragmentation, the strand breaks activity and the modulator role on the methylation status of genomic repetitive sequences of HL-60 promyelocytic cells. Whereas none tested compounds showed toxic or genotoxic effect, all tested compounds exerted antitoxic and antigenotoxic activity in Drosophila. Glucose, classic Red Bull® and sugar-free Red Bull® were cytotoxic in HL-60 cell line. Classic Red Bull® induced DNA internucleosomal fragmentation although none of them exhibited DNA damage on human leukaemia cells. In conclusion, the tested compounds are safe on Drosophila melanogaster and classic Red Bull® could overall possess nutraceutical potential in the in vivo and in vitro model used in this study. Besides, taurine could holistically be one of the bioactive compounds responsible for the biological activity of classic Red Bull®.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Samira Sanami ◽  
Fatemeh Azadegan-Dehkordi ◽  
Mahmoud Rafieian-Kopaei ◽  
Majid Salehi ◽  
Maryam Ghasemi-Dehnoo ◽  
...  

AbstractCervical cancer, caused by human papillomavirus (HPV), is the fourth most common type of cancer among women worldwide. While HPV prophylactic vaccines are available, they have no therapeutic effects and do not clear up existing infections. This study aims to design a therapeutic vaccine against cervical cancer using reverse vaccinology. In this study, the E6 and E7 oncoproteins from HPV16 were chosen as the target antigens for epitope prediction. Cytotoxic T lymphocytes (CTL) and helper T lymphocytes (HTL) epitopes were predicted, and the best epitopes were selected based on antigenicity, allergenicity, and toxicity. The final vaccine construct was composed of the selected epitopes, along with the appropriate adjuvant and linkers. The multi-epitope vaccine was evaluated in terms of physicochemical properties, antigenicity, and allergenicity. The tertiary structure of the vaccine construct was predicted. Furthermore, several analyses were also carried out, including molecular docking, molecular dynamics (MD) simulation, and in silico cloning of the vaccine construct. The results showed that the final proposed vaccine could be considered an effective therapeutic vaccine for HPV; however, in vitro and in vivo experiments are required to validate the efficacy of this vaccine candidate.


Blood ◽  
1996 ◽  
Vol 87 (5) ◽  
pp. 1862-1872 ◽  
Author(s):  
M Introna ◽  
VV Alles ◽  
M Castellano ◽  
G Picardi ◽  
L De Gioia ◽  
...  

Abstract Pentraxins, which include C reactive protein (CRP) and serum amyloid P component (SAP), are prototypic acute phase reactants that serve as indicators of inflammatory reactions. Here we report genomic and cDNA cloning of mouse ptx3 (mptx3), a member of the pentraxin gene family and characterize its extrahepatic expression in vitro and in vivo. mptx3 is organized into three exons on chromosome 3: the first (43 aa) and second exon (175 aa) code for the signal peptide and for a protein portion with no high similarity to known sequences the third (203 aa) for a domain related to classical pentraxins, which contains the “pentraxin family signature.” Analysis of the N terminal portion predicts a predominantly alpha helical structure, while the pentraxin domain of ptx3 is accommodated comfortably in the tertiary structure fold of SAP. Normal and transformed fibroblasts, undifferentiated and differentiated myoblasts, normal endothelial cells, and mononuclear phagocytes express mptx3 mRNA and release the protein in vitro on exposure to interleukin-1beta (IL-1beta) and tumor necrosis factor (TNF)alpha. mptx3 was induced by bacterial lipopolysaccharide in vivo in a variety of organs and, most strongly, in the vascular endothelium of skeletal muscle and heart. Thus, mptx3 shows a distinct pattern of in vivo expression indicative of a significant role in cardiovascular and inflammatory pathology.


2005 ◽  
Vol 91 (3) ◽  
pp. 492-498 ◽  
Author(s):  
Xiang Xiao ◽  
Tianping Wang ◽  
Xiaodong Zheng ◽  
Guangjing Shen ◽  
Zhigang Tian
Keyword(s):  

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