scholarly journals Eukaryotic genome evolution: rearrangement and coevolution of compartmentalized genetic information

2003 ◽  
Vol 358 (1429) ◽  
pp. 87-97 ◽  
Author(s):  
Reinhold G. Herrmann ◽  
Rainer M. Maier ◽  
Christian Schmitz-Linneweber
Keyword(s):  
Nicotiana Tabacum ◽  
Gene Transfer ◽  
Genetic Information ◽  
Entire System ◽  
Atropa Belladonna ◽  
Closely Related Species ◽  
Photosynthetic Machinery ◽  
Organismic Evolution ◽  
Almost All ◽  
Multicellular Organisms

The plant cell operates with an integrated, compartmentalized genome consisting of nucleus/cytosol, plastids and mitochondria that, in its entirety, is regulated in time, quantitatively, in multicellular organisms and also in space. This genome, as do genomes of eukaryotes in general, originated in endosymbiotic events, with at least three cells, and was shaped phylogenetically by a massive and highly complex restructuring and intermixing of the genetic potentials of the symbiotic partners and by lateral gene transfer. This was accompanied by fundamental changes in expression signals in the entire system at almost all regulatory levels. The gross genome rearrangements contrast with a highly specific compartmental interplay, which becomes apparent in interspecific nuclear-plastid cybrids or hybrids. Organelle exchanges, even between closely related species, can greatly disturb the intracellular genetic balance (‘hybrid bleaching’), which is indicative of compartmental coevolution and is of relevance for speciation processes. The photosynthetic machinery of plastids, which is embedded in that genetic machinery, is an appealing model to probe into genomic and organismic evolution and to develop functional molecular genomics. We have studied the reciprocal Atropa belladonna-Nicotiana tabacum cybrids, which differ markedly in their phenotypes, and found that transcriptional and post-transcriptional processes can contribute to genome/plastome incompatibility. Allopolyploidy can influence this phenomenon by providing an increased, cryptic RNA editing potential and the capacity to maintain the integrity of organelles of different taxonomic origins.

scholarly journals Poxviral Strategies to Overcome Host Cell Apoptosis

Pathogens ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 6
Author(s):  
Chathura D. Suraweera ◽  
Mark G. Hinds ◽  
Marc Kvansakul
Keyword(s):  
Viral Infections ◽  
B Cell Lymphoma ◽  
Intrinsic Apoptosis ◽  
Host Cell Apoptosis ◽  
Successful Infection ◽  
Infected Cells ◽  
Host Virus Interactions ◽  
Almost All ◽  
Virus Interactions ◽  
Multicellular Organisms

Apoptosis is a form of cellular suicide initiated either via extracellular (extrinsic apoptosis) or intracellular (intrinsic apoptosis) cues. This form of programmed cell death plays a crucial role in development and tissue homeostasis in multicellular organisms and its dysregulation is an underlying cause for many diseases. Intrinsic apoptosis is regulated by members of the evolutionarily conserved B-cell lymphoma-2 (Bcl-2) family, a family that consists of pro- and anti-apoptotic members. Bcl-2 genes have also been assimilated by numerous viruses including pox viruses, in particular the sub-family of chordopoxviridae, a group of viruses known to infect almost all vertebrates. The viral Bcl-2 proteins are virulence factors and aid the evasion of host immune defenses by mimicking the activity of their cellular counterparts. Viral Bcl-2 genes have proved essential for the survival of virus infected cells and structural studies have shown that though they often share very little sequence identity with their cellular counterparts, they have near-identical 3D structures. However, their mechanisms of action are varied. In this review, we examine the structural biology, molecular interactions, and detailed mechanism of action of poxvirus encoded apoptosis inhibitors and how they impact on host–virus interactions to ultimately enable successful infection and propagation of viral infections.

scholarly journals Horizontally transferred genes in the ctenophore Mnemiopsis leidyi encode enzymes and are expressed during early development

2017 ◽  
Author(s):  
Alexandra M Hernandez ◽  
Joseph F Ryan
Keyword(s):  
Antibiotic Resistance ◽  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Early Development ◽  
Genetic Information ◽  
Mnemiopsis Leidyi ◽  
Uncharacterized Protein ◽  
Phylogenetic Incongruence ◽  
Wide Range ◽  
Growing Body

Horizontal gene transfer has had major impacts on the biology of a wide range of organisms from antibiotic resistance in bacteria to adaptations to herbivory in arthropods. A growing body of literature shows that horizontal gene transfer (HGT) between non-animals and animals is more commonplace than previously thought. In this study, we present a thorough investigation of HGT in the ctenophore Mnemiopsis leidyi. We applied tests of phylogenetic incongruence to identify nine genes that were likely transferred horizontally early in ctenophore evolution from bacteria and non-metazoan eukaryotes. All but one of these HGTs (an uncharacterized protein) appear to perform enzymatic activities in M. leidyi, supporting previous observations that enzymes are more likely to be retained after HGT events. We found that the majority of these nine horizontally transferred genes were expressed during early development, suggesting that they are active and play a role in the biology of M. leidyi. This is the first report of HGT in ctenophores, and contributes to an ever-growing literature on the prevalence of genetic information flowing between non-animals and animals.

Molecular Paleontology and Biochemical Evolution

2008 ◽  
Author(s):  
Susan M. Gaines ◽  
Geoffrey Eglinton ◽  
Jürgen Rullkötter
Keyword(s):  
Twentieth Century ◽  
Cambrian Explosion ◽  
Microbial World ◽  
Form And Function ◽  
The Past ◽  
Unicellular Algae ◽  
Almost All ◽  
And Function ◽  
Multicellular Organisms ◽  
Molecular Paleontology

Carl Woese’s drive for a unified system of biological classification didn’t just open the microbial world to exploration: it reshuffled the entire taxonomic system and revolutionized the way that biologists study evolution, reigniting interest in preanimal evolution. Studies of evolution from the mid-nineteenth through most of the twentieth century relied on the comparison of forms in living and fossil organisms and were limited to the complex multicellular organisms that developed over the past 550 million years. In other words, much was known about the evolution of animals and land plants that left distinctive hard fossils, and very little was known about the unicellular algae and microorganisms that occupied the seas for most of the earth’s history. Woese’s Tree of Life, derived from nucleic acid sequences in ribosomal RNA, has revealed ancestral relationships that form and function don’t even hint at, allowing biologists to look beyond the rise of multicellular life and link it with less differentiated, more primal forms—which was precisely Woese’s intention. But evolution is a history, not just a family tree of relationships. If the information stored in the genes of extant organisms is to provide true insight into that history, it needs to be anchored in time, linked to extinct organisms and to past environments. Ultimately, we must look to the record in the rocks and sediments, just as paleontologists and biologists have been doing for the past two centuries. In Darwin’s time, that record comprised rocks from the past 550 million years, a span of time that geologists now call the Phanerozoic eon, based on Greek words meaning visible or evident life. The eon began with the rocks of the Cambrian period, in which nineteenth- and early-twentieth-century paleontologists discovered a fabulous assortment of fossils—traces of trilobites, anemones, shrimp, and other multicellular animals that were completely missing from any of the earlier strata. Thousands of new animals and plants, including representatives of almost all contemporary groups, as well as hundreds of now-extinct ones, appeared so suddenly between 542 and 530 million years ago that paleontologists refer to the phenomenon as the Cambrian “explosion.”

The Plastid Chromosome of Atropa belladonna and its Comparison with that of Nicotiana tabacum: The Role of RNA Editing in Generating Divergence in the Process of Plant Speciation

2002 ◽  
Vol 19 (9) ◽  
pp. 1602-1612 ◽  
Author(s):  
Christian Schmitz-Linneweber ◽  
Ralph Regel ◽  
Tung Gia Du ◽  
Holger Hupfer ◽  
Reinhold G. Herrmann ◽  
...  
Keyword(s):  
Nicotiana Tabacum ◽  
Rna Editing ◽  
Atropa Belladonna ◽  
Plastid Chromosome

scholarly journals Metabolic effects of pesticide effluents on Nicotiana tabacum and Vigna radiata plants

2015 ◽  
Vol 4 (2) ◽  
pp. 87-94
Author(s):  
Kumkum Mishra ◽  
Eera Sanwal ◽  
PK Tandon ◽  
Kiran Gupta
Keyword(s):  
Nicotiana Tabacum ◽  
Enzymatic Activity ◽  
Vigna Radiata ◽  
Sugar Content ◽  
Metabolic Parameters ◽  
Metabolic Effects ◽  
Mda Content ◽  
Catalase Peroxidase ◽  
Almost All ◽  
Industry Effluent

Some important metabolic parameters were investigated in relation to various doses of pesticide effluents in two economically plants viz. Nicotiana and Vigna plants. Increasing doses of pesticide effluents caused decrease in both sugar and protein concentration almost similarly in both plants. However, activities of enzymes, catalase, peroxidase and MDA content were found to be stimulated by higher doses of pesticide factory effluents in both the plants. Protein and sugar content decreased at all doses in Nicotiana tabacum however there were increase in enzymatic activity like catalase and peroxidase. MDA content was also increased in same plant. On the other hand Vigna radiata showed inducing nature of protein content at lower concentration (25%) and thereafter inhibit at all doses while sugar content decreased at all concentrations. Enzymatic activity viz. catalase and peroxidase showed promoting nature at all concentrations. MDA content also increased at all concentrations. Thus it can be concluded that but for small differences in almost all the metabolic parameters towards their response towards pesticide industry effluent both the studied plants i.e. Nicotiana and Vigna were found to be quite susceptible towards pesticide effluents. DOI: http://dx.doi.org/10.3126/ije.v4i2.12628 International Journal of Environment Vol.4(2) 2015: 87-94

scholarly journals Evolutionary insights into Mariner-like elements in Apis species

2020 ◽  
Author(s):  
Kakeru Yokoi ◽  
Kiyoshi Kimura ◽  
Hidemasa Bono
Keyword(s):  
Phylogenetic Analysis ◽  
Transposable Element ◽  
Related Species ◽  
Horizontal Transfer ◽  
The Other ◽  
Closely Related Species ◽  
Sequences Analysis ◽  
Almost All

AbstractBackgroundMariner and mariner-like elements (MLEs) are distributed in various species and their sequences are highly diverse. In previous reports, a few transposable element in the genomes of Apis species mainly consist of mariner and MLE. For further insight of Apis MLEs, detailed classifications of Apis MLE and sequences analysis of long MLEs, which may potentially encode the transposase, are needed.ResultsMuch more MLEs were detected in A. mellifera genome compared to other Apis species genomes. They were classified into 31 Drosophila MLE classes. In this classification, almost all of MLEs were classified into the three classes belonging to mellifera subfamilies, suggesting that Apis MLEs which exist thorough Apis species derived from single MLE belonging to mellifera subfamily. Phylogenetic analysis using MLEs in the three classes showed that there two types of clusters, of which one consist of multiple Apis species MLEs, and others of only A. mellifera MLEs. Long MLEs analysis showed that only one long MLE encoding complete transposase was found in all Apis genome except for A. mellifera genome, and the MLE and multiple MLEs similar to it were found in A. mellifera genome. The analysis also showed that other several long MLEs encoding complete transposase were found only in A. mellifera genome.ConclusionsAlmost all of Apis MLEs are mellifera subfamilies. Of these MLEs, one types of them settled in Apis species and burst in A. mellifera genome. The other one of MLEs invaded into A. mellifera genome by horizontal transfer and exploded in A. mellifera genome. This is the first example of the finer aspects of MLE evolution among closely related species.

scholarly journals Phylogenetic analysis of genomic islands in closely-related species belonging to Sinorhizobium sp.

2020 ◽  
Author(s):  
M. E. Vladimirova ◽  
V. S. Muntyan ◽  
A. S. Saksaganskaya ◽  
B. V. Simarov ◽  
M. L. Roumiantseva
Keyword(s):  
Phylogenetic Analysis ◽  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Related Species ◽  
Genomic Islands ◽  
Closely Related Species ◽  
Homologous Sequences

Genomic islands of closely related S. meliloti and S. medicae species were evaluated and homologous sequences were identified; it has been suggested that horizontal gene transfer occurs at homologous tRNA sites.

scholarly journals Alternative Biochemistries for Alien Life: Basic Concepts and Requirements for the Design of a Robust Biocontainment System in Genetic Isolation

Genes ◽  
2018 ◽  
Vol 10 (1) ◽  
pp. 17 ◽  
Author(s):  
Christian Diwo ◽  
Nediljko Budisa
Keyword(s):  
Genetic Code ◽  
Genetic Information ◽  
Information Transfer ◽  
De Novo ◽  
Genetic Isolation ◽  
Universal Genetic Code ◽  
Synthetic Life ◽  
Beneficial Traits ◽  
Genetic Pool ◽  
Almost All

The universal genetic code, which is the foundation of cellular organization for almost all organisms, has fostered the exchange of genetic information from very different paths of evolution. The result of this communication network of potentially beneficial traits can be observed as modern biodiversity. Today, the genetic modification techniques of synthetic biology allow for the design of specialized organisms and their employment as tools, creating an artificial biodiversity based on the same universal genetic code. As there is no natural barrier towards the proliferation of genetic information which confers an advantage for a certain species, the naturally evolved genetic pool could be irreversibly altered if modified genetic information is exchanged. We argue that an alien genetic code which is incompatible with nature is likely to assure the inhibition of all mechanisms of genetic information transfer in an open environment. The two conceivable routes to synthetic life are either de novo cellular design or the successive alienation of a complex biological organism through laboratory evolution. Here, we present the strategies that have been utilized to fundamentally alter the genetic code in its decoding rules or its molecular representation and anticipate future avenues in the pursuit of robust biocontainment.

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