scholarly journals A plant mitochondrial sequence transcribed in transgenic tobacco chloroplasts is not edited.

1995 ◽  
Vol 15 (3) ◽  
pp. 1377-1381 ◽  
Author(s):  
C A Sutton ◽  
O V Zoubenko ◽  
M R Hanson ◽  
P Maliga
Keyword(s):  
Transgenic Tobacco ◽  
Rna Editing ◽  
Ribosomal Protein Gene ◽  
Regulatory Sequences ◽  
Mitochondrial Rna ◽  
Higher Plant ◽  
Rna Sequences ◽  
Exon 2 ◽  
Chimeric Genes ◽  
Gene Regulatory

RNA editing occurs in two higher-plant organelles, chloroplasts and mitochondria. Because chloroplasts and mitochondria exhibit some similarity in editing site selection, we investigated whether mitochondrial RNA sequences could be edited in chloroplasts. We produced transgenic tobacco plants that contained chimeric genes in which the second exon of a Petunia hybrida mitochondrial coxII gene was under the control of chloroplast gene regulatory sequences. coxII transcripts accumulated to low or high levels in transgenic chloroplasts containing chimeric genes with the plastid ribosomal protein gene rps16 or the rRNA operon promoter, respectively. Exon 2 of coxII was chosen because it carries seven editing sites and is edited in petunia mitochondria even when located in an abnormal context in an aberrant recombined gene. When editing of the coxII transcripts in transgenic chloroplasts was examined, no RNA editing at any of the usual sites was detected, nor was there any novel editing at any other sites. These results indicate that the RNA editing mechanisms of chloroplasts and mitochondria are not identical but must have at least some organelle-specific components.

scholarly journals Molecular Evolution: The Perplexing Diversity of Mitochondrial RNA Editing Systems

2016 ◽  
Vol 26 (1) ◽  
pp. R22-R24 ◽  
Author(s):  
Daniel B. Sloan ◽  
Zhiqiang Wu
Keyword(s):  
Molecular Evolution ◽  
Rna Editing ◽  
Mitochondrial Rna

scholarly journals Role of Transposable Elements in Gene Regulation in the Human Genome

Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 118
Author(s):  
Arsala Ali ◽  
Kyudong Han ◽  
Ping Liang
Keyword(s):  
Gene Regulation ◽  
Transposable Elements ◽  
Regulatory Sequences ◽  
Rna Sequences ◽  
Expression Of Genes ◽  
Wide Range ◽  
Lineage Specificity ◽  
Regulatory Rnas ◽  
Potential Factors ◽  
Interspersed Repeats

Transposable elements (TEs), also known as mobile elements (MEs), are interspersed repeats that constitute a major fraction of the genomes of higher organisms. As one of their important functional impacts on gene function and genome evolution, TEs participate in regulating the expression of genes nearby and even far away at transcriptional and post-transcriptional levels. There are two known principal ways by which TEs regulate the expression of genes. First, TEs provide cis-regulatory sequences in the genome with their intrinsic regulatory properties for their own expression, making them potential factors for regulating the expression of the host genes. TE-derived cis-regulatory sites are found in promoter and enhancer elements, providing binding sites for a wide range of trans-acting factors. Second, TEs encode for regulatory RNAs with their sequences showed to be present in a substantial fraction of miRNAs and long non-coding RNAs (lncRNAs), indicating the TE origin of these RNAs. Furthermore, TEs sequences were found to be critical for regulatory functions of these RNAs, including binding to the target mRNA. TEs thus provide crucial regulatory roles by being part of cis-regulatory and regulatory RNA sequences. Moreover, both TE-derived cis-regulatory sequences and TE-derived regulatory RNAs have been implicated in providing evolutionary novelty to gene regulation. These TE-derived regulatory mechanisms also tend to function in a tissue-specific fashion. In this review, we aim to comprehensively cover the studies regarding these two aspects of TE-mediated gene regulation, mainly focusing on the mechanisms, contribution of different types of TEs, differential roles among tissue types, and lineage-specificity, based on data mostly in humans.

Precise assignment of the heavy-strand promoter of mouse mitochondrial DNA: cognate start sites are not required for transcriptional initiation

1986 ◽  
Vol 6 (9) ◽  
pp. 3262-3267
Author(s):  
D D Chang ◽  
D A Clayton
Keyword(s):  
Mitochondrial Dna ◽  
Dna Sequences ◽  
High Rate ◽  
In Vitro Assays ◽  
Regulatory Sequences ◽  
Sufficient Information ◽  
Mitochondrial Rna ◽  
Loop Region ◽  
Heavy Strand

Transcription of the heavy strand of mouse mitochondrial DNA starts from two closely spaced, distinct sites located in the displacement loop region of the genome. We report here an analysis of regulatory sequences required for faithful transcription from these two sites. Data obtained from in vitro assays demonstrated that a 51-base-pair region, encompassing nucleotides -40 to +11 of the downstream start site, contains sufficient information for accurate transcription from both start sites. Deletion of the 3' flanking sequences, including one or both start sites to -17, resulted in the initiation of transcription by the mitochondrial RNA polymerase from alternative sites within vector DNA sequences. This feature places the mouse heavy-strand promoter uniquely among other known mitochondrial promoters, all of which absolutely require cognate start sites for transcription. Comparison of the heavy-strand promoter with those of other vertebrate mitochondrial DNAs revealed a remarkably high rate of sequence divergence among species.

scholarly journals Recognition of RNA Editing Sites Is Directed by Unique Proteins in Chloroplasts: Biochemical Identification of cis-Acting Elements and trans-Acting Factors Involved in RNA Editing in Tobacco and Pea Chloroplasts

2002 ◽  
Vol 22 (19) ◽  
pp. 6726-6734 ◽  
Author(s):  
Tetsuya Miyamoto ◽  
Junichi Obokata ◽  
Masahiro Sugiura
Keyword(s):  
Rna Editing ◽  
Editing Site ◽  
Mrna Editing ◽  
Higher Plant ◽  
In Vitro System ◽  
Cis Acting ◽  
Biochemical Identification ◽  
Editing Activity

ABSTRACT RNA editing in higher-plant chloroplasts involves C-to-U conversions at specific sites. Although in vivo analyses have been performed, little is known about the biochemical aspects of chloroplast editing reactions. Here we improved our original in vitro system and devised a procedure for preparing active chloroplast extracts not only from tobacco plants but also from pea plants. Using our tobacco in vitro system, cis-acting elements were defined for psbE and petB mRNAs. Distinct proteins were found to bind specifically to each cis-element, a 56-kDa protein to the psbE site and a 70-kDa species to the petB site. Pea chloroplasts lack the corresponding editing site in psbE since T is already present in the DNA. Parallel in vitro analyses with tobacco and pea extracts revealed that the pea plant has no editing activity for psbE mRNAs and lacks the 56-kDa protein, whereas petB mRNAs are edited and the 70-kDa protein is also present. Therefore, coevolution of an editing site and its cognate trans-factor was demonstrated biochemically in psbE mRNA editing between tobacco and pea plants.

scholarly journals A Mathematical Analysis of HDV Genotypes: From Molecules to Cells

Mathematics ◽  
2021 ◽  
Vol 9 (17) ◽  
pp. 2063
Author(s):  
Rami Zakh ◽  
Alexander Churkin ◽  
Franziska Totzeck ◽  
Marina Parr ◽  
Tamir Tuller ◽  
...  
Keyword(s):  
Rna Editing ◽  
Virus Replication ◽  
Mathematical Analysis ◽  
Graph Representation ◽  
Genotype 3 ◽  
Mutational Robustness ◽  
Rna Sequences ◽  
Stem Loop ◽  
Hepatitis D ◽  
Hdv Genotype

Hepatitis D virus (HDV) is classified according to eight genotypes. The various genotypes are included in the HDVdb database, where each HDV sequence is specified by its genotype. In this contribution, a mathematical analysis is performed on RNA sequences in HDVdb. The RNA folding predicted structures of the Genbank HDV genome sequences in HDVdb are classified according to their coarse-grain tree-graph representation. The analysis allows discarding in a simple and efficient way the vast majority of the sequences that exhibit a rod-like structure, which is important for the virus replication, to attempt to discover other biological functions by structure consideration. After the filtering, there remain only a small number of sequences that can be checked for their additional stem-loops besides the main one that is known to be responsible for virus replication. It is found that a few sequences contain an additional stem-loop that is responsible for RNA editing or other possible functions. These few sequences are grouped into two main classes, one that is well-known experimentally belonging to genotype 3 for patients from South America associated with RNA editing, and the other that is not known at present belonging to genotype 7 for patients from Cameroon. The possibility that another function besides virus replication reminiscent of the editing mechanism in HDV genotype 3 exists in HDV genotype 7 has not been explored before and is predicted by eigenvalue analysis. Finally, when comparing native and shuffled sequences, it is shown that HDV sequences belonging to all genotypes are accentuated in their mutational robustness and thermodynamic stability as compared to other viruses that were subjected to such an analysis.

scholarly journals Functional effects of variation in transcription factor binding highlight long-range gene regulation by epromoters

2019 ◽  
Author(s):  
Joanna Mitchelmore ◽  
Nastasiya Grinberg ◽  
Chris Wallace ◽  
Mikhail Spivakov
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Statistical Power ◽  
Target Genes ◽  
Allelic Variation ◽  
Regulatory Function ◽  
Regulatory Sequences ◽  
Distal Enhancer ◽  
Association Testing ◽  
Gene Regulatory

AbstractIdentifying DNA cis-regulatory modules (CRMs) that control the expression of specific genes is crucial for deciphering the logic of transcriptional control. Natural genetic variation can point to the possible gene regulatory function of specific sequences through their allelic associations with gene expression. However, comprehensive identification of causal regulatory sequences in brute-force association testing without incorporating prior knowledge is challenging due to limited statistical power and effects of linkage disequilibrium. Sequence variants affecting transcription factor (TF) binding at CRMs have a strong potential to influence gene regulatory function, which provides a motivation for prioritising such variants in association testing. Here, we generate an atlas of CRMs showing predicted allelic variation in TF binding affinity in human lymphoblastoid cell lines (LCLs) and test their association with the expression of their putative target genes inferred from Promoter Capture Hi-C and immediate linear proximity. We reveal over 1300 CRM TF-binding variants associated with target gene expression, the majority of them undetected with standard association testing. A large proportion of CRMs showing associations with the expression of genes they contact in 3D localise to the promoter regions of other genes, supporting the notion of ‘epromoters’: dual-action CRMs with promoter and distal enhancer activity.

scholarly journals PRESa2i: incremental decision trees for prediction of Adenosine to Inosine RNA editing sites

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 262
Author(s):  
Alif Choyon ◽  
Ashiqur Rahman ◽  
Md. Hasanuzzaman ◽  
Dewan Md Farid ◽  
Swakkhar Shatabda
Keyword(s):  
Rna Editing ◽  
Web Application ◽  
State Of The Art ◽  
Independent Set ◽  
Prediction Tool ◽  
Decision Tree Algorithm ◽  
Rna Sequences ◽  
Feature Selection Technique ◽  
Selection Technique ◽  
Protein Encoding

RNA editing is a very crucial cellular process affecting protein encoding and is sometimes correlated with the cause of fatal diseases, such as cancer. Thus knowledge about RNA editing sites in a RNA sequence is very important. Adenosine to Inosine (A-to-I) is the most common of the RNA editing events. In this paper,we present PRESa2i, a computation prediction tool for identification of A-to-I RNA editing sites in given RNA sequences. PRESa2i uses a simple, yet effective set of sequence based features generated from RNA sequences and a novel feature selection technique. It uses an incremental decision tree algorithm as the classification algorithm. On a standard benchmark dataset and independent set, it achieves 86.48% accuracy and 90.67% sensitivity and significantly outperforms state-of-the-art methods. We have also implemented a web application based on PRESa2i and made it available freely at: http://brl.uiu.ac.bd/presa2i/index.php. The materials for this paper are also available to use from: https://github.com/swakkhar/RNA-Editing/.

scholarly journals RNA Recognition Motif-Containing Protein ORRM4 Broadly Affects Mitochondrial RNA Editing and Impacts Plant Development and Flowering

2015 ◽  
Vol 170 (1) ◽  
pp. 294-309 ◽  
Author(s):  
Xiaowen Shi ◽  
Arnaud Germain ◽  
Maureen R. Hanson ◽  
Stéphane Bentolila
Keyword(s):  
Rna Editing ◽  
Plant Development ◽  
Rna Recognition Motif ◽  
Mitochondrial Rna ◽  
Rna Recognition ◽  
Recognition Motif

scholarly journals Efficient site-specific cleavage by RNase MRP requires interaction with two evolutionarily conserved mitochondrial RNA sequences.

1990 ◽  
Vol 10 (5) ◽  
pp. 2191-2201 ◽  
Author(s):  
J L Bennett ◽  
D A Clayton
Keyword(s):  
Sequence Homology ◽  
Mammalian Species ◽  
Saturation Mutagenesis ◽  
Mitochondrial Rna ◽  
Rna Sequences ◽  
Site Specific ◽  
Conserved Sequence ◽  
Sequence Block ◽  
Rnase Mrp

RNase MRP is a site-specific endonuclease that processes primer mitochondrial RNA from the leading-strand origin of mitochondrial DNA replication. Using deletional analysis and saturation mutagenesis, we have determined the substrate requirements for cleavage by mouse mitochondrial RNase MRP. Two regions of sequence homology among vertebrate mitochondrial RNA primers, conserved sequence blocks II and III, were found to be critical for both efficient and accurate cleavage; a third region of sequence homology, conserved sequence block I, was dispensable. Analysis of insertion and deletion mutations within conserved sequence block II demonstrated that the specificity of RNase MRP accommodates the natural sequence heterogeneity of conserved sequence block II in vivo. Heterologous assays with human RNase MRP and mutated mouse mitochondrial RNA substrates indicated that sequences essential for substrate recognition are conserved between mammalian species.

Sign in / Sign up

Export Citation Format

Share Document