scholarly journals In vitro study of processing of the intron-encoded U16 small nucleolar RNA in Xenopus laevis.

1994 ◽  
Vol 14 (5) ◽  
pp. 2966-2974 ◽  
Author(s):  
E Caffarelli ◽  
M Arese ◽  
B Santoro ◽  
P Fragapane ◽  
I Bozzoni
Keyword(s):  
Xenopus Laevis ◽  
In Vitro Study ◽  
Ribosomal Protein Gene ◽  
Common Mechanism ◽  
Protein Coding ◽  
New Class ◽  
Nuclear Extracts ◽  
In Vitro Processing ◽  
New Type

It was recently shown that a new class of small nuclear RNAs is encoded in introns of protein-coding genes and that they originate by processing of the pre-mRNA in which they are contained. Little is known about the mechanism and the factors involved in this new type of processing. The L1 ribosomal protein gene of Xenopus laevis is a well-suited system for studying this phenomenon: several different introns encode for two small nucleolar RNAs (snoRNAs; U16 and U18). In this paper, we analyzed the in vitro processing of these snoRNAs and showed that both are released from the pre-mRNA by a common mechanism: endonucleolytic cleavages convert the pre-mRNA into a precursor snoRNA with 5' and 3' trailer sequences. Subsequently, trimming converts the pre-snoRNAs into mature molecules. Oocyte and HeLa nuclear extracts are able to process X. laevis and human substrates in a similar manner, indicating that the processing of this class of snoRNAs relies on a common and evolutionarily conserved mechanism. In addition, we found that the cleavage activity is strongly enhanced in the presence of Mn2+ ions.

In vitro study of processing of the intron-encoded U16 small nucleolar RNA in Xenopus laevis

1994 ◽  
Vol 14 (5) ◽  
pp. 2966-2974
Author(s):  
E Caffarelli ◽  
M Arese ◽  
B Santoro ◽  
P Fragapane ◽  
I Bozzoni
Keyword(s):  
Xenopus Laevis ◽  
In Vitro Study ◽  
Ribosomal Protein Gene ◽  
Common Mechanism ◽  
Protein Coding ◽  
New Class ◽  
Nuclear Extracts ◽  
In Vitro Processing ◽  
New Type

It was recently shown that a new class of small nuclear RNAs is encoded in introns of protein-coding genes and that they originate by processing of the pre-mRNA in which they are contained. Little is known about the mechanism and the factors involved in this new type of processing. The L1 ribosomal protein gene of Xenopus laevis is a well-suited system for studying this phenomenon: several different introns encode for two small nucleolar RNAs (snoRNAs; U16 and U18). In this paper, we analyzed the in vitro processing of these snoRNAs and showed that both are released from the pre-mRNA by a common mechanism: endonucleolytic cleavages convert the pre-mRNA into a precursor snoRNA with 5' and 3' trailer sequences. Subsequently, trimming converts the pre-snoRNAs into mature molecules. Oocyte and HeLa nuclear extracts are able to process X. laevis and human substrates in a similar manner, indicating that the processing of this class of snoRNAs relies on a common and evolutionarily conserved mechanism. In addition, we found that the cleavage activity is strongly enhanced in the presence of Mn2+ ions.

scholarly journals Efficacy of monepantel against lower developmental stages of a multi-resistant and susceptible Haemonchus contortus isolates: an in vitro study

2013 ◽  
Vol 50 (2) ◽  
pp. 91-95 ◽  
Author(s):  
L. Lecová ◽  
L. Stuchlíková ◽  
J. Lamka ◽  
M. Špulák ◽  
M. Várady ◽  
...  
Keyword(s):  
Haemonchus Contortus ◽  
Developmental Stages ◽  
In Vitro Study ◽  
Lethal Concentration ◽  
In Vitro Tests ◽  
High Efficacy ◽  
Larval Stages ◽  
New Class ◽  
Ovicidal Effect

AbstractMonepantel (MOP) belongs to a new class of anthelmintic compounds, the amino-acetonitrile derivates, which have a different mode of action as the currently used anthelmintics. Many present studies confirmed the high efficacy of MOP against fourth larval and adult stages of Haemonchus contortus. The objective of this study was to determine in vitro efficacy of MOP against lower development stages (eggs, L1–L3 larvae) and to compare it between resistant and susceptible isolates of H. contortus. For this purpose, two in vitro tests - egg hatch test and micro-agar larval development test were used. Results were quantified as 50 % lethal concentration (LC50), 99 % lethal concentration (LC99) and resistance factor (RF). This study revealed the high efficacy against lower larval stages (L1–L3) of both resistant and susceptible strains of this parasite. Larval susceptibility was not dependent of the sensitivity status of the nematode isolate. On the other hand, ovicidal effect of MOP was very low.

3'end maturation of the Chlamydomonas reinhardtii chloroplast atpB mRNA is a two-step process

1993 ◽  
Vol 13 (4) ◽  
pp. 2277-2285
Author(s):  
D B Stern ◽  
K L Kindle
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Higher Plants ◽  
Transcription Termination ◽  
Protein Coding ◽  
Coding Regions ◽  
In Vitro Processing ◽  
Mrna Precursor ◽  
Chloroplast Transcripts

Inverted repeat (IR) sequences are found at the 3' ends of most chloroplast protein coding regions, and we have previously shown that the 3'IR is important for accumulation of atpB mRNA in Chlamydomonas reinhardtii (D. B. Stern, E.R. Radwanski, and K. L. Kindle, Plant Cell 3:285-297, 1991). In vitro studies indicate that 3' IRs are inefficient transcription termination signals in higher plants and have furthermore defined processing activities that act on the 3' ends of chloroplast transcripts, suggesting that most chloroplast mRNAs are processed at their 3' ends in vivo. To investigate the mechanism of 3' end processing in Chlamydomonas reinhardtii chloroplasts, the maturation of atpB mRNA was examined in vitro and in vivo. In vitro, a synthetic atpB mRNA precursor is rapidly cleaved at a position 10 nucleotides downstream from the mature 3' terminus. This cleavage is followed by exonucleolytic processing to generate the mature 3' end. In vivo run-on transcription experiments indicate that a maximum of 50% of atpB transcripts are transcriptionally terminated at or near the IR, while the remainder are subject to 3' end processing. Analysis of transcripts derived from chimeric atpB genes introduced into Chlamydomonas chloroplasts by biolistic transformation suggests that in vivo processing and in vitro processing occur by similar or identical mechanisms.

scholarly journals Composition and processing activity of a semi-recombinant holo U7 snRNP

2019 ◽  
Vol 48 (3) ◽  
pp. 1508-1530 ◽  
Author(s):  
Katarzyna Bucholc ◽  
Wei Shen Aik ◽  
Xiao-cui Yang ◽  
Kaituo Wang ◽  
Z Hong Zhou ◽  
...  
Keyword(s):  
Animal Cells ◽  
Sm Proteins ◽  
Nuclear Extracts ◽  
In Vitro Processing ◽  
Functionally Impaired ◽  
Catalytically Active ◽  
U7 Snrnp ◽  
Core Components ◽  
Processing Activity

Abstract In animal cells, replication-dependent histone pre-mRNAs are cleaved at the 3′ end by U7 snRNP consisting of two core components: a ∼60-nucleotide U7 snRNA and a ring of seven proteins, with Lsm10 and Lsm11 replacing the spliceosomal SmD1 and SmD2. Lsm11 interacts with FLASH and together they recruit the endonuclease CPSF73 and other polyadenylation factors, forming catalytically active holo U7 snRNP. Here, we assembled core U7 snRNP bound to FLASH from recombinant components and analyzed its appearance by electron microscopy and ability to support histone pre-mRNA processing in the presence of polyadenylation factors from nuclear extracts. We demonstrate that semi-recombinant holo U7 snRNP reconstituted in this manner has the same composition and functional properties as endogenous U7 snRNP, and accurately cleaves histone pre-mRNAs in a reconstituted in vitro processing reaction. We also demonstrate that the U7-specific Sm ring assembles efficiently in vitro on a spliceosomal Sm site but the engineered U7 snRNP is functionally impaired. This approach offers a unique opportunity to study the importance of various regions in the Sm proteins and U7 snRNA in 3′ end processing of histone pre-mRNAs.

scholarly journals Effect of the Electromagnetic Field (EMF) Radiation on Transcriptomic Profile of Pig Myometrium during the Peri-Implantation Period—An In Vitro Study

2021 ◽  
Vol 22 (14) ◽  
pp. 7322
Author(s):  
Ewa Monika Drzewiecka ◽  
Wiktoria Kozlowska ◽  
Lukasz Paukszto ◽  
Agata Zmijewska ◽  
Pawel Jozef Wydorski ◽  
...  
Keyword(s):  
Electromagnetic Field ◽  
Immune Responses ◽  
In Vitro Study ◽  
Active Regions ◽  
Differentially Expressed ◽  
Single Nucleotide Variants ◽  
Protein Coding ◽  
Transcriptomic Profile ◽  
Implantation Period

The electromagnetic field (EMF) affects the physiological processes in mammals, but the molecular background of the observed alterations remains not well established. In this study was tested the effect of short duration (2 h) of the EMF treatment (50 Hz, 8 mT) on global transcriptomic alterations in the myometrium of pigs during the peri-implantation period using next-generation sequencing. As a result, the EMF treatment affected the expression of 215 transcript active regions (TARs), and among them, the assigned gene protein-coding biotype possessed 90 ones (differentially expressed genes, DEGs), categorized mostly to gene ontology terms connected with defense and immune responses, and secretion and export. Evaluated DEGs enrich the KEGG TNF signaling pathway, and regulation of IFNA signaling and interferon-alpha/beta signaling REACTOME pathways. There were evaluated 12 differentially expressed long non-coding RNAs (DE-lnc-RNAs) and 182 predicted single nucleotide variants (SNVs) substitutions within RNA editing sites. In conclusion, the EMF treatment in the myometrium collected during the peri-implantation period affects the expression of genes involved in defense and immune responses. The study also gives new insight into the mechanisms of the EMF action in the regulation of the transcriptomic profile through lnc-RNAs and SNVs.

scholarly journals Oryzalin and Gamma Radiation Induced Polyploidization in Garden Balsam Plants (Impatiens balsamina L.) In Vitro

2017 ◽  
Vol 5 (1) ◽  
pp. 01-05 ◽  
Author(s):  
Made Defiani ◽  
Ida Astarini ◽  
Eniek Kriswiyanti
Keyword(s):  
Gamma Radiation ◽  
Gamma Ray ◽  
In Vitro Study ◽  
Leaf Section ◽  
Plant Variation ◽  
In Vitro Methods ◽  
Impatiens Balsamina ◽  
Radiation Induced ◽  
New Type

The aim of the research was to create genetic variation on garden balsam using oryzalin and Gamma radiation. Mutagenic agent may improve plant variation. Garden balsam seeds were treated by oryzalin (0%, 0.01%, 0.02%) then the seedlings were planted in the field four times to gain seeds generation M4. Seedlings of M4 (7 days of age) were radiated by gamma ray 60Co (0, 5, 10, 15 Gy) and planted in the field to collect seeds for in vitro study to induce a new type of mutant plant. In vitro methods was conducted to achieved rapid micropropagation of Impatiens balsamina L. mutant plants. Growth percentage of seedlings reached 90% by gibberellin 0.01 ppm. Leaf section used for explant and cultured in MS media enriched by 0.5 ppm NAA and 0.5 ppm BAP aseptically. Shoots were regenerated on 6 weeks after cultured however some shoots become vitrification. Number of chromosome varied (mixoploid) on treated plants (M5). Form of secondary metabolites ( alkaloids and terpenoids ) in the roots extract was not changed by oryzalin and gamma radiation. Mixoploid explants showed variation in morphology and some treatments only had little shoots and a treatment has vigorous roots. Control plants have shoot and callus.

In-Vitro Study of Sol Gel Synthesized Bioactive Glass Ceramics for Anti-Microbial Properties

2021 ◽  
Vol 21 (3) ◽  
pp. 1606-1612
Author(s):  
Narender Ranga ◽  
Atul Kumar ◽  
C. R. Mariappan ◽  
Surender Duhan
Keyword(s):  
Structural Information ◽  
Sol Gel ◽  
Research Work ◽  
Glass Ceramics ◽  
In Vitro Study ◽  
Apatite Formation ◽  
E Coli ◽  
Transmission Electron ◽  
New Type

In this research work new type of bioglass ceramics successfully synthesized the bioglass composition: 50SiO2−30CaO−10P2O5−10MgO by sol–gel technique which was further heated up to 600 °C. Different characterization techniques were applied on the prepared bioglass powder to obtain the structural information. X-ray powder diffraction (XRD) and fourier-transform infrared spectroscopy (FTIR) analysis confirms the amorphous nature and apatite formation on surface of the sample. The time dependent biological activity was tested on immersed samples with simulated body fluid (SBF). Structural configuration of the hydroxyapatite layer along with nano-size as well as texture properties of the samples were confirmed using field emission scanning electron microscope (FE-SEM), high-resolution transmission electron microscopy (HR-TEM) and Brunauer–Emmett–Teller (BET) techniques, respectively. It was found that magnesium performs a pivotal role in bone proliferation and improves the thermophysical properties of the synthesized bioglass ceramics. The antibacterial effects were studied by two well-known pathogen Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus).

scholarly journals Mechanical Pull-Out Test of a New Hybrid Fixture-Abutment Connection: An In Vitro Study

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1555
Author(s):  
Gianmaria D’addazio ◽  
Bruna Sinjari ◽  
Lorenzo Arcuri ◽  
Beatrice Femminella ◽  
Giovanna Murmura ◽  
...  
Keyword(s):  
Surface Modification ◽  
In Vitro Study ◽  
Mean Value ◽  
Vitro Study ◽  
Test Machine ◽  
Pull Out ◽  
Significant Difference ◽  
Implant Abutment ◽  
New Type

Implant abutment connection was described among the main causes of peri-implant bone resorption. The aim of this in vitro study was to test the coupling capacity, the surface modification of a new hybrid connection and the influence of repeated connection activations caused during the main clinical and laboratory phases. A total of 40 implant-abutment screw retained systems with 10°-conical and internal hexagon connection were tested. The connection was screwed, fixed to the universal test machine, removed the screw and a pull-out test was performed. Test was repeated five times in succession. Also Scanning Electron Microscopy (SEM) was used to detect microscopically surface modification. Analysis of variance and Tukey tests were used for the statistical analysis. Pull-out test reveals a mean value of 131.35 ± 16.52 Newton Centimeter (N·cm). For each single activation, results from first to fifth were: 113.9 ± 13.02, 126.1 ± 12.81, 138.11 ± 15.15, 138.8 ± 11.90 and 140 ± 12.99 N·cm. A statistically significant difference between the measurements and an increase in the removal force was shown. The collected data supports the use of this new type of connection, resulting in a very strong interface between implant and abutment. Also, repeated activation of connection can promote a better coupling of the implant-abutment interface.

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