scholarly journals In silico prediction of mtDNA Gene Expression Based on Codon Usage Bias in Ants (Formicidae Latreille, 1802) that Inhabit Limestone Quarry Ecosystems

2018 ◽  
Vol 2 (1) ◽  
pp. 32
Author(s):  
Semir Dorić ◽  
Dinko Osmanković ◽  
Lada Lukić Bilela
Keyword(s):  
Gene Expression ◽  
Codon Usage ◽  
Codon Usage Bias ◽  
In Silico ◽  
Expression Patterns ◽  
Mitochondrial Protein ◽  
Model Organisms ◽  
Molecular Response ◽  
Protein Coding ◽  
Protein Coding Genes

Codon usage is considered as a modulator of gene expression, due to high correlation between codon usage, tRNA abundance and the level of gene expression. Adaptability is primarily manifested at gene level therefore mtDNA gene expression analysis may indicate trends toward the development of adaptive traits for specific environmental conditions. Moreover, modified gene expression patterns may result from such adaptations. Due to their sensitivity to environmental disturbances, great functional importance and accessibility ants (Family: Formicidae Latreille, 1802) are excellent model organisms for  molecular and bioinformatics genome analysis. This in silico simulation is based on the comparison of codon usage bias and the level of gene expression of currently available mitochondrial protein-coding genes of ant species that were sampled at quarry Ribnica (Kakanj, Bosnia and Herzegovina). MILC and MELP algorithms were used forcodon usage bias analysis and mitochondrial gene expression prediction, respectively. The analysis included four mtDNA protein-coding genes from eight selected species of ants totaling in 32 protein sequences. The results of codon usage analysis indicated no statistically significant differences in codon usage bias, as well as relative frequencies of the gene expression level.  The next step should be directed to molecular ecology studies, even using whole genome measures of gene expression (RNA-seq; transcriptomics) to capture molecular response to environmental challenges.

scholarly journals Cell Biology of the Trypanosome Genome

2010 ◽  
Vol 74 (4) ◽  
pp. 552-569 ◽  
Author(s):  
Jan-Peter Daniels ◽  
Keith Gull ◽  
Bill Wickstead
Keyword(s):  
Gene Expression ◽  
Cell Biology ◽  
Nuclear Organization ◽  
Nuclear Architecture ◽  
Gene Clusters ◽  
Model Organisms ◽  
Protein Coding ◽  
African Trypanosomes ◽  
Protein Coding Genes ◽  
A Genome

SUMMARY Trypanosomes are a group of protozoan eukaryotes, many of which are major parasites of humans and livestock. The genomes of trypanosomes and their modes of gene expression differ in several important aspects from those of other eukaryotic model organisms. Protein-coding genes are organized in large directional gene clusters on a genome-wide scale, and their polycistronic transcription is not generally regulated at initiation. Transcripts from these polycistrons are processed by global trans-splicing of pre-mRNA. Furthermore, in African trypanosomes, some protein-coding genes are transcribed by a multifunctional RNA polymerase I from a specialized extranucleolar compartment. The primary DNA sequence of the trypanosome genomes and their cellular organization have usually been treated as separate entities. However, it is becoming increasingly clear that in order to understand how a genome functions in a living cell, we will need to unravel how the one-dimensional genomic sequence and its trans-acting factors are arranged in the three-dimensional space of the eukaryotic nucleus. Understanding this cell biology of the genome will be crucial if we are to elucidate the genetic control mechanisms of parasitism. Here, we integrate the concepts of nuclear architecture, deduced largely from studies of yeast and mammalian nuclei, with recent developments in our knowledge of the trypanosome genome, gene expression, and nuclear organization. We also compare this nuclear organization to those in other systems in order to shed light on the evolution of nuclear architecture in eukaryotes.

scholarly journals Analysis of Mutation Bias in Shaping Codon Usage Bias and Its Association with Gene Expression Across Species

10.29007/87r9 ◽  
2020 ◽  
Author(s):  
Zhixiu Lu ◽  
Michael Gilchrist ◽  
Scott Emrich
Keyword(s):  
Gene Expression ◽  
Codon Usage ◽  
Codon Usage Bias ◽  
Synonymous Codon ◽  
Synonymous Codon Usage ◽  
Mutation Bias ◽  
Protein Coding ◽  
E Coli ◽  
Synonymous Codons ◽  
Computation Efficiency

Codon usage bias has been known to reflect the expression level of a protein-coding gene under the evolutionary theory that selection favors certain synonymous codons. Although measuring the effect of selection in simple organisms such as yeast and E. coli has proven to be effective and accurate, codon-based methods perform less well in plants and humans. In this paper, we extend a prior method that incorporates another evolutionary factor, namely mutation bias and its effect on codon usage. Our results indicate that prediction of gene expression is significantly improved under our framework, and suggests that quantification of mutation bias is essential for fully understanding synonymous codon usage. We also propose an improved method, namely MLE-Φ, with much greater computation efficiency and a wider range of applications. An implementation of this method is provided at https://github.com/luzhixiu1996/MLE- Phi.

scholarly journals In silico screen identifies a new Toxoplasma gondii mitochondrial ribosomal protein essential for mitochondrial translation

2019 ◽  
Author(s):  
Alice Lacombe ◽  
Andrew E. Maclean ◽  
Jana Ovciarikova ◽  
Julie Tottey ◽  
Lilach Sheiner
Keyword(s):  
In Silico ◽  
Expression Patterns ◽  
Mitochondrial Protein ◽  
Small Subunit ◽  
Model Organisms ◽  
Macromolecular Complex ◽  
Mitochondrial Translation ◽  
Apicomplexan Parasites ◽  
Subunit Protein ◽  
Mitochondrial Functions

SummaryApicomplexan parasites cause diseases such as malaria and toxoplasmosis. The apicomplexan mitochondrion shows striking differences from common model organisms, including in fundamental processes such as mitochondrial translation. Despite evidence that mitochondrial translation is essential for parasites survival, it is largely understudied. Progress has been restricted by the absence of functional assays to detect apicomplexan mitochondrial translation, a lack of knowledge of proteins involved in the process and the inability to identify and detect mitoribosomes.Using mRNA expression patterns, 279 candidate mitochondrial housekeeping components were identified in Toxoplasma. 11 were validated, including the mitoribosomal small subunit protein 35 (TgmS35). TgmS35 tagging enabled the detection of a macromolecular complex corresponding to the mitoribosomal small subunit for the first time in apicomplexans. A new analytical pipeline detected defects in mitochondrial translation upon TgmS35 depletion, while other mitochondrial functions remain unaffected. Our work lays a foundation for the study of apicomplexan mitochondrial translation.Abbreviated summaryThe apicomplexan mitochondrion is divergent and essential yet poorly studied. Mitochondrial translation is predicted to utilize ribosomes assembled from fragmented rRNA but this was never shown. Knowing the mitochondrial protein content is critical for these studies. We identified 11 new mitochondrial proteins via in-silico searches. Tagging and depletion of a mitoribosomal small subunit protein enabled the first detection of a macromolecular ribosomal complex, and provided proof of principle for our new mitochondrial translation analytic pipeline.

Polyphyletic Origins of Schizothoracinae Fishes (Cyprinidae) in Respect to Their Mitochondrial Protein-Coding Genes

2019 ◽  
Vol 07 (02) ◽  
Author(s):  
Saira Bibi ◽  
Muhammad Fiaz Khan ◽  
Aqsa Rehman ◽  
Faisal Nouroz
Keyword(s):  
Mitochondrial Protein ◽  
Protein Coding ◽  
Protein Coding Genes

Analysis of Inter-Chromosomal Distribution of Disease-Related Genes in Human Genome

2020 ◽  
Vol 21 (11) ◽  
pp. 1068-1077
Author(s):  
Xiaochao Sun ◽  
Bin Yang ◽  
Qunye Zhang
Keyword(s):  
Spatial Distribution ◽  
Model Organisms ◽  
Nucleotide Polymorphisms ◽  
Chromosomal Distribution ◽  
Single Nucleotide ◽  
Protein Coding ◽  
Single Chromosome ◽  
Deletion Mutations ◽  
Protein Coding Genes ◽  
Disease Related Genes

: Many studies have shown that the spatial distribution of genes within a single chromosome exhibits distinct patterns. However, little is known about the characteristics of inter-chromosomal distribution of genes (including protein-coding genes, processed transcripts and pseudogenes) in different genomes. In this study, we explored these issues using the available genomic data of both human and model organisms. Moreover, we also analyzed the distribution pattern of protein-coding genes that have been associated with 14 common diseases and the insert/deletion mutations and single nucleotide polymorphisms detected by whole genome sequencing in an acute promyelocyte leukemia patient. We obtained the following novel findings. Firstly, inter-chromosomal distribution of genes displays a nonstochastic pattern and the gene densities in different chromosomes are heterogeneous. This kind of heterogeneity is observed in genomes of both lower and higher species. Secondly, protein-coding genes involved in certain biological processes tend to be enriched in one or a few chromosomes. Our findings have added new insights into our understanding of the spatial distribution of genome and disease- related genes across chromosomes. These results could be useful in improving the efficiency of disease-associated gene screening studies by targeting specific chromosomes.

Patterns of Nucleotide Substitution in Mitochondrial Protein Coding Genes of Vertebrates

Genetics ◽  
1996 ◽  
Vol 143 (1) ◽  
pp. 537-548 ◽  
Author(s):  
Sudhir Kumar
Keyword(s):  
Nucleotide Substitution ◽  
Mitochondrial Protein ◽  
Likelihood Estimation ◽  
Nucleotide Composition ◽  
Substitution Rates ◽  
Protein Coding ◽  
Protein Coding Genes ◽  
Conserved Genes ◽  
Maximum Likelihood Methods ◽  
Position Data

Abstract Maximum likelihood methods were used to study the differences in substitution rates among the four nucleotides and among different nucleotide sites in mitochondrial protein-coding genes of vertebrates. In the lst+2nd codon position data, the frequency of nucleotide G is negatively correlated with evolutionary rates of genes, substitution rates vary substantially among sites, and the transition / transversion rate bias (R) is two to five times larger than that expected at random. Generally, largest transition biases and greatest differences in substitution rates among sites are found in the highly conserved genes. The 3rd positions in placental mammal genes exhibit strong nucleotide composition biases and the transitional rates exceed transversional rates by one to two orders of magnitude. Tamura-Nei and Hasegawa-Kishino-Yano models with gamma distributed variable rates among sites (gamma parameter, α) adequately describe the nucleotide substitution process in 1st+2nd position data. In these data, ignoring differences in substitution rates among sites leads to largest biases while estimating substitution rates. Kimura's two-parameter model with variable-rates among sites performs satisfactorily in likelihood estimation of R, α, and overall amount of evolution for lst+2nd position data. It can also be used to estimate pairwise distances with appropriate values of α for a majority of genes.

scholarly journals Mitogenome Analysis of Four Lamiinae Species (Coleoptera: Cerambycidae) and Gene Expression Responses by Monochamus alternatus When Infected with the Parasitic Nematode, Bursaphelenchus mucronatus

Insects ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 453
Author(s):  
Zi-Yi Zhang ◽  
Jia-Yin Guan ◽  
Yu-Rou Cao ◽  
Xin-Yi Dai ◽  
Kenneth B. Storey ◽  
...  
Keyword(s):  
Gene Expression ◽  
Phylogenetic Trees ◽  
Mitochondrial Gene ◽  
Mitochondrial Protein ◽  
Pine Wilt Disease ◽  
Bursaphelenchus Xylophilus ◽  
Monochamus Alternatus ◽  
Genome Database ◽  
Protein Coding ◽  
Nd5 Gene

We determined the mitochondrial gene sequence of Monochamus alternatus and three other mitogenomes of Lamiinae (Insect: Coleoptera: Cerambycidae) belonging to three genera (Aulaconotus, Apriona and Paraglenea) to enrich the mitochondrial genome database of Lamiinae and further explore the phylogenetic relationships within the subfamily. Phylogenetic trees of the Lamiinae were built using the Bayesian inference (BI) and maximum likelihood (ML) methods and the monophyly of Monochamus, Anoplophora, and Batocera genera was supported. Anoplophora chinensis, An. glabripennis and Aristobia reticulator were closely related, suggesting they may also be potential vectors for the transmission of the pine wood pathogenic nematode (Bursaphelenchus xylophilus) in addition to M. alternatus, a well-known vector of pine wilt disease. There is a special symbiotic relationship between M. alternatus and Bursaphelenchus xylophilus. As the native sympatric sibling species of B. xylophilus, B. mucronatus also has a specific relationship that is often overlooked. The analysis of mitochondrial gene expression aimed to explore the effect of B. mucronatus on the energy metabolism of the respiratory chain of M. alternatus adults. Using RT-qPCR, we determined and analyzed the expression of eight mitochondrial protein-coding genes (COI, COII, COIII, ND1, ND4, ND5, ATP6, and Cty b) between M. alternatus infected by B. mucronatus and M. alternatus without the nematode. Expression of all the eight mitochondrial genes were up-regulated, particularly the ND4 and ND5 gene, which were up-regulated by 4–5-fold (p < 0.01). Since longicorn beetles have immune responses to nematodes, we believe that their relationship should not be viewed as symbiotic, but classed as parasitic.

Sign in / Sign up

Export Citation Format

Share Document