scholarly journals Mechanisms of Gene Duplication and Translocation and Progress towards Understanding Their Relative Contributions to Animal Genome Evolution

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Olivia Mendivil Ramos ◽  
David E. K. Ferrier
Keyword(s):  
Gene Duplication ◽  
Genome Evolution ◽  
Sequence Data ◽  
Genetic Material ◽  
Genetic Change ◽  
Genome Organisation ◽  
Base Pairs ◽  
Duplication Events ◽  
Major Route ◽  
Animal Genomes

Duplication of genetic material is clearly a major route to genetic change, with consequences for both evolution and disease. A variety of forms and mechanisms of duplication are recognised, operating across the scales of a few base pairs upto entire genomes. With the ever-increasing amounts of gene and genome sequence data that are becoming available, our understanding of the extent of duplication is greatly improving, both in terms of the scales of duplication events as well as their rates of occurrence. An accurate understanding of these processes is vital if we are to properly understand important events in evolution as well as mechanisms operating at the level of genome organisation. Here we will focus on duplication in animal genomes and how the duplicated sequences are distributed, with the aim of maintaining a focus on principles of evolution and organisation that are most directly applicable to the shaping of our own genome.

scholarly journals Genome evolution of SARS-CoV-2 and its virological characteristics

2020 ◽  
Vol 40 (1) ◽  
Author(s):  
So Nakagawa ◽  
Takayuki Miyazawa
Keyword(s):  
Genome Evolution ◽  
Genome Sequence ◽  
Causative Agent ◽  
Sequence Data ◽  
Genome Sequences ◽  
Genome Sequence Data ◽  
Global Prevalence ◽  
Horseshoe Bats

AbstractCoronavirus disease of 2019 (COVID-19), which originated in China in 2019, shows mild cold and pneumonia symptoms that can occasionally worsen and result in deaths. SARS-CoV-2 was reported to be the causative agent of the disease and was identified as being similar to SARS-CoV, a causative agent of SARS in 2003. In this review, we described the phylogeny of SARS-CoV-2, covering various related studies, in particular, focusing on viruses obtained from horseshoe bats and pangolins that belong to Sarbecovirus, a subgenus of Betacoronavirus. We also describe the virological characteristics of SARS-CoV-2 and compare them with other coronaviruses. More than 30,000 genome sequences of SARS-CoV-2 are available in the GISAID database as of May 28, 2020. Using the genome sequence data of closely related viruses, the genomic characteristics and evolution of SARS-CoV-2 were extensively studied. However, given the global prevalence of COVID-19 and the large number of associated deaths, further computational and experimental virological analyses are required to fully characterize SARS-CoV-2.

scholarly journals The First Glimpse of Streptocarpus ionanthus (Gesneriaceae) Phylogenomics: Analysis of Five Subspecies’ Chloroplast Genomes

Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 456 ◽  
Author(s):  
Cornelius M. Kyalo ◽  
Zhi-Zhong Li ◽  
Elijah M. Mkala ◽  
Itambo Malombe ◽  
Guang-Wan Hu ◽  
...  
Keyword(s):  
Phylogenetic Relationships ◽  
Sequence Data ◽  
Structural Features ◽  
Base Pairs ◽  
Protein Coding ◽  
Variable Regions ◽  
Morphological Heterogeneity ◽  
Chloroplast Genomes ◽  
Chloroplast Genome Sequence ◽  
Phylogenomic Analyses

Streptocarpus ionanthus (Gesneriaceae) comprise nine herbaceous subspecies, endemic to Kenya and Tanzania. The evolution of Str. ionanthus is perceived as complex due to morphological heterogeneity and unresolved phylogenetic relationships. Our study seeks to understand the molecular variation within Str. ionanthus using a phylogenomic approach. We sequence the chloroplast genomes of five subspecies of Str. ionanthus, compare their structural features and identify divergent regions. The five genomes are identical, with a conserved structure, a narrow size range (170 base pairs (bp)) and 115 unique genes (80 protein-coding, 31 tRNAs and 4 rRNAs). Genome alignment exhibits high synteny while the number of Simple Sequence Repeats (SSRs) are observed to be low (varying from 37 to 41), indicating high similarity. We identify ten divergent regions, including five variable regions (psbM, rps3, atpF-atpH, psbC-psbZ and psaA-ycf3) and five genes with a high number of polymorphic sites (rps16, rpoC2, rpoB, ycf1 and ndhA) which could be investigated further for phylogenetic utility in Str. ionanthus. Phylogenomic analyses here exhibit low polymorphism within Str. ionanthus and poor phylogenetic separation, which might be attributed to recent divergence. The complete chloroplast genome sequence data concerning the five subspecies provides genomic resources which can be expanded for future elucidation of Str. ionanthus phylogenetic relationships.

Genetic Material and Sequence Data to Protect Global Health in the Light of Pandemic Outbreaks: Mapping the Legal Landscape under European and International Law

2020 ◽  
Vol 27 (3) ◽  
pp. 232-241
Author(s):  
Claudia Seitz
Keyword(s):  
Global Health ◽  
International Law ◽  
Sequence Data ◽  
Influenza Pandemic ◽  
Genetic Material ◽  
World Health ◽  
The European Union ◽  
Corona Virus ◽  
Health Organization ◽  
The Eu

Abstract The current pandemic outbreak of corona virus SARS-CoV-2 shows the need for comprehensive European cooperation in drug development and the importance of genetic material and sequence data in research concerning this unknown disease. As corona virus SARS-CoV-2 is spreading across Europe and worldwide, national authorities and the European Union (EU) institutions do their utmost to address the pandemic and accelerate innovation to protect global health. In order to be prepared and to be able to respond immediately to serious epidemic and pandemic diseases, the EU has already adopted the Decision No (EU) 1082/2013 on serious cross-border threats to health. The World Health Organization (WHO) has established a global system to collect genetic material and information to protect a global influenza pandemic outbreak. The article describes the current legal landscape under EU and international law.

Genetic Diversity and Origin of Siam Weed (Chromolaena odorata) in Australia

1998 ◽  
Vol 12 (1) ◽  
pp. 27-31 ◽  
Author(s):  
Leon J. Scott ◽  
Corinna L. Lange ◽  
Glenn C. Graham ◽  
David K. Yeates
Keyword(s):  
Genetic Diversity ◽  
Internal Transcribed Spacer ◽  
Sequence Data ◽  
Southern Brazil ◽  
Chromolaena Odorata ◽  
Base Pairs ◽  
Its1 Sequence ◽  
Its1 Region ◽  
Native And Introduced Ranges ◽  
The U.S

Asynchronous flowering was noted in a recently discovered infestation of siam weed in north Queensland. This may indicate some genetic diversity in the infestation, increasing concerns about the origin of the infestation. Internal transcribed spacer 1 (ITS1) sequence data were obtained for siam weed individuals from north Queensland, Indonesia, Thailand, South Africa, Ivory Coast, Brazil, Colombia, and the U.S. The ITS1 region is 258 base pairs long, and the populations that flower at different times in north Queensland differ by four base substitutions. The genotype common in north Queensland is also reported throughout the native and introduced ranges. The other genotype is reported only in north Queensland and southern Brazil. These data, in conjunction with prior investigations into possible origins, indicate that Brazil is the most likely source of the infestation in Australia.

A new species of big-headed, fanged dicroglossine frog (Genus Limnonectes) from Thailand

Zootaxa ◽  
2008 ◽  
Vol 1807 (1) ◽  
pp. 26 ◽  
Author(s):  
DAVID S. McLEOD
Keyword(s):  
New Species ◽  
Dna Sequence ◽  
Sequence Data ◽  
Sequence Divergence ◽  
Type Material ◽  
Base Pairs ◽  
Dna Sequence Data ◽  
16S Gene ◽  
A New Species

A new species of the dicroglossine genus Limnonectes from eastern Thailand and its tadpole are described. Analysis of DNA sequence data from 2518 base-pairs of the mitochondrial 12S and 16S gene regions places the species within the complex of frogs currently referred to as Limnonectes kuhlii and demonstrates it to be a separate lineage (>18% sequence divergence from type-material of L. kuhlii from Java). The new species differs from L. kuhlii by having nuptial pads, a greater snout–vent length, and different relative finger lengths than specimens from Java. It has more extensive toe webbing, a different arrangement of nuptial pads, and a greater snout–vent length than Limnonectes laticeps. The new species, which lacks vocal slits, also can be distinguished from the morphologically similar Limnonectes namiyei from Japan, which possesses vocal slits.

Evolution of Placental Function in Mammals: The Molecular Basis of Gas and Nutrient Transfer, Hormone Secretion, and Immune Responses

2012 ◽  
Vol 92 (4) ◽  
pp. 1543-1576 ◽  
Author(s):  
Anthony M. Carter
Keyword(s):  
Gene Duplication ◽  
Convergent Evolution ◽  
Globin Gene ◽  
Hormone Secretion ◽  
Human Leukocyte ◽  
Amino Acid Transporters ◽  
Placental Lactogens ◽  
Wide Range ◽  
Duplication Events ◽  
Range Of Functions

Placenta has a wide range of functions. Some are supported by novel genes that have evolved following gene duplication events while others require acquisition of gene expression by the trophoblast. Although not expressed in the placenta, high-affinity fetal hemoglobins play a key role in placental gas exchange. They evolved following duplications within the beta-globin gene family with convergent evolution occurring in ruminants and primates. In primates there was also an interesting rearrangement of a cassette of genes in relation to an upstream locus control region. Substrate transfer from mother to fetus is maintained by expression of classic sugar and amino acid transporters at the trophoblast microvillous and basal membranes. In contrast, placental peptide hormones have arisen largely by gene duplication, yielding for example chorionic gonadotropins from the luteinizing hormone gene and placental lactogens from the growth hormone and prolactin genes. There has been a remarkable degree of convergent evolution with placental lactogens emerging separately in the ruminant, rodent, and primate lineages and chorionic gonadotropins evolving separately in equids and higher primates. Finally, coevolution in the primate lineage of killer immunoglobulin-like receptors and human leukocyte antigens can be linked to the deep invasion of the uterus by trophoblast that is a characteristic feature of human placentation.

Characterizing mutagenic effects of recombination through a sequence-level genetic map

Science ◽  
2019 ◽  
Vol 363 (6425) ◽  
pp. eaau1043 ◽  
Author(s):  
Bjarni V. Halldorsson ◽  
Gunnar Palsson ◽  
Olafur A. Stefansson ◽  
Hakon Jonsson ◽  
Marteinn T. Hardarson ◽  
...  
Keyword(s):  
Genetic Map ◽  
Meiotic Recombination ◽  
De Novo ◽  
Sequence Data ◽  
Mutagenic Effect ◽  
Whole Genome Sequence ◽  
De Novo Mutation ◽  
Base Pairs ◽  
Males And Females ◽  
Mutagenic Effects

Genetic diversity arises from recombination and de novo mutation (DNM). Using a combination of microarray genotype and whole-genome sequence data on parent-child pairs, we identified 4,531,535 crossover recombinations and 200,435 DNMs. The resulting genetic map has a resolution of 682 base pairs. Crossovers exhibit a mutagenic effect, with overrepresentation of DNMs within 1 kilobase of crossovers in males and females. In females, a higher mutation rate is observed up to 40 kilobases from crossovers, particularly for complex crossovers, which increase with maternal age. We identified 35 loci associated with the recombination rate or the location of crossovers, demonstrating extensive genetic control of meiotic recombination, and our results highlight genes linked to the formation of the synaptonemal complex as determinants of crossovers.

scholarly journals DNA Barcoding: Mixed results for big-headed flies (Diptera: Pipunculidae)

Zootaxa ◽  
2007 ◽  
Vol 1423 (1) ◽  
pp. 1-26 ◽  
Author(s):  
JEFFREY H. SKEVINGTON ◽  
CHRISTIAN KEHLMAIER ◽  
GUNILLA STÅHLS
Keyword(s):  
Dna Barcoding ◽  
Sequence Data ◽  
Phylogenetic Signal ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Base Pairs ◽  
Data Set ◽  
Taxonomic Decision ◽  
Morphological Species

Sequence data from 658 base pairs of mitochondrial cytochrome c oxidase I (cox1) were analysed for 28 described species of Pipunculidae (Diptera) in an effort to test the concept of DNA Barcoding on this family. Two recently revised but distantly related pipunculid lineages with presumed different evolutionary histories were used for the test (Clistoabdominalis Skevington, 2001 and Nephrocerus Zetterstedt, 1838). An effort was made to test the concept using sister taxa and morphologically similar sibling species swarms in these two genera. Morphological species concepts for Clistoabdominalis taxa were either supported by cox1 data or found to be too broad. Most of the discordance could be accounted for after reassessing morphological characters. In these cases, the molecular data were invaluable in assisting taxonomic decision-making. The radiation of Nearctic species of Nephrocerus could not be diagnosed using cox1. The ability of cox1 to recover phylogenetic signal was also tested on Clistoabdominalis. Morphological data for Clistoabdominalis were combined with the molecular data set. The pipunculid phylogeny from molecular data closely resembles the published phylogeny based on morphology. Partitioned Bremer support is used to localize areas of conflict between the datasets.

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