scholarly journals Exploring the evolutionary process of alkannin/shikonin O-acyltransferases by a reliable Lithospermum erythrorhizon genome

DNA Research ◽  
2021 ◽  
Vol 28 (5) ◽  
Author(s):  
Chengyi Tang
Keyword(s):  
Gene Duplication ◽  
Positive Selection ◽  
Genome Size ◽  
Coming Out ◽  
Draft Genome ◽  
Evolutionary Process ◽  
Functional Differentiation ◽  
Acid Sites ◽  
Lithospermum Erythrorhizon ◽  
Size Estimation

Abstract Increasing genome data are coming out. Genome size estimation plays an essential role in guiding genome assembly. Several months ago, other researchers were the first to publish a draft genome of the red gromwell (i.e. Lithospermum erythrorhizon). However, we considered that the genome size they estimated and assembled was incorrect. This study meticulously estimated the L. erythrorhizon genome size to should be ∼708.74 Mb and further provided a reliable genome version (size ≈ 693.34 Mb; contigN50 length ≈ 238.08 Kb) to support our objection. Furthermore, according to our genome, we identified a gene family of the alkannin/shikonin O-acyltransferases (i.e. AAT/SAT) that catalysed enantiomer-specific acylations in the alkannin/shikonin biosynthesis (a characteristic metabolic pathway in L. erythrorhizon’s roots) and further explored its evolutionary process. The results indicated that the existing AAT/SAT were not generated from only one round of gene duplication but three rounds; after different rounds of gene duplication, the existing AAT/SAT and their recent ancestors were under positive selection at different amino acid sites. These suggested that a combined power from gene duplication plus positive selection plausibly propelled AAT/SAT’s functional differentiation in evolution.

scholarly journals First Draft Genome Sequence of Salmonella enterica subsp. enterica Serovar Enteritidis Isolated from the Chicken Meat in Russia

Proceedings ◽  
2020 ◽  
Vol 76 (1) ◽  
pp. 2
Author(s):  
Alexey V. Rakov ◽  
Anatoly A. Yakovlev ◽  
Viacheslav V. Sinkov
Keyword(s):  
Genome Size ◽  
Genome Sequence ◽  
Salmonella Enterica ◽  
Salmonella Enteritidis ◽  
Reference Strain ◽  
Draft Genome ◽  
Noncoding Rnas ◽  
Gallus Domesticus ◽  
Gallus Gallus Domesticus ◽  
Zoonotic Pathogens

Salmonella enterica subsp. enterica serovar Enteritidis is one of the most common zoonotic pathogens. We report here the genome sequence of Salmonella enterica subsp. enterica serovar Enteritidis S-25048 isolated from chicken (Gallus gallus domesticus) meat in Artyom, Russia. The assembled genome size was 4,695,145 bp. A total of 4565 coding genes, four rRNAs, 62 tRNAs, and 14 noncoding RNAs were predicted. To our knowledge, this is the first publically deposited annotated genome of this serovar isolated in Russia. The Salmonella Enteritidis S-25048 genome is suitable for use as a reference strain of Salmonella Enteritidis isolated in Russia.

scholarly journals Genome Size Diversity in Rare, Endangered, and Protected Orchids in Poland

Genes ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 563
Author(s):  
Monika Rewers ◽  
Iwona Jedrzejczyk ◽  
Agnieszka Rewicz ◽  
Anna Jakubska-Busse
Keyword(s):  
Genome Size ◽  
Species Identification ◽  
Dna Content ◽  
Size Estimation ◽  
Orchid Species ◽  
Infraspecific Taxon ◽  
2C Dna Content ◽  
Plant Families ◽  
Liparis Loeselii ◽  
Identification And Characterization

Orchidaceae is one of the largest and the most widespread plant families with many species threatened with extinction. However, only about 1.5% of orchids’ genome sizes have been known so far. The aim of this study was to estimate the genome size of 15 species and one infraspecific taxon of endangered and protected orchids growing wild in Poland to assess their variability and develop additional criterion useful in orchid species identification and characterization. Flow cytometric genome size estimation revealed that investigated orchid species possessed intermediate, large, and very large genomes. The smallest 2C DNA content possessed Liparis loeselii (14.15 pg), while the largest Cypripedium calceolus (82.10 pg). It was confirmed that the genome size is characteristic to the subfamily. Additionally, for four species Epipactis albensis, Ophrys insectifera, Orchis mascula, Orchis militaris and one infraspecific taxon, Epipactis purpurata f. chlorophylla the 2C DNA content has been estimated for the first time. Genome size estimation by flow cytometry proved to be a useful auxiliary method for quick orchid species identification and characterization.

scholarly journals Codon-Substitution Models for Heterogeneous Selection Pressure at Amino Acid Sites

Genetics ◽  
2000 ◽  
Vol 155 (1) ◽  
pp. 431-449 ◽  
Author(s):  
Ziheng Yang ◽  
Rasmus Nielsen ◽  
Nick Goldman ◽  
Anne-Mette Krabbe Pedersen
Keyword(s):  
Amino Acid ◽  
Positive Selection ◽  
Selective Pressure ◽  
Acid Sites ◽  
Data Sets ◽  
Protein Coding ◽  
Important Indicator ◽  
Diversifying Selection ◽  
Codon Substitution ◽  
Neutral Mutations

AbstractComparison of relative fixation rates of synonymous (silent) and nonsynonymous (amino acid-altering) mutations provides a means for understanding the mechanisms of molecular sequence evolution. The nonsynonymous/synonymous rate ratio (ω = dN/dS) is an important indicator of selective pressure at the protein level, with ω = 1 meaning neutral mutations, ω < 1 purifying selection, and ω > 1 diversifying positive selection. Amino acid sites in a protein are expected to be under different selective pressures and have different underlying ω ratios. We develop models that account for heterogeneous ω ratios among amino acid sites and apply them to phylogenetic analyses of protein-coding DNA sequences. These models are useful for testing for adaptive molecular evolution and identifying amino acid sites under diversifying selection. Ten data sets of genes from nuclear, mitochondrial, and viral genomes are analyzed to estimate the distributions of ω among sites. In all data sets analyzed, the selective pressure indicated by the ω ratio is found to be highly heterogeneous among sites. Previously unsuspected Darwinian selection is detected in several genes in which the average ω ratio across sites is <1, but in which some sites are clearly under diversifying selection with ω > 1. Genes undergoing positive selection include the β-globin gene from vertebrates, mitochondrial protein-coding genes from hominoids, the hemagglutinin (HA) gene from human influenza virus A, and HIV-1 env, vif, and pol genes. Tests for the presence of positively selected sites and their subsequent identification appear quite robust to the specific distributional form assumed for ω and can be achieved using any of several models we implement. However, we encountered difficulties in estimating the precise distribution of ω among sites from real data sets.

First estimates of genome size in ribbon worms (phylum Nemertea) using flow cytometry and Feulgen image analysis densitometry

2014 ◽  
Vol 92 (10) ◽  
pp. 847-851 ◽  
Author(s):  
Kelly L. Mulligan ◽  
Terra C. Hiebert ◽  
Nicholas W. Jeffery ◽  
T. Ryan Gregory
Keyword(s):  
Flow Cytometry ◽  
Image Analysis ◽  
Body Size ◽  
Genome Size ◽  
Positive Relationship ◽  
Nuclear Dna ◽  
Nuclear Dna Content ◽  
Size Estimation ◽  
Size Diversity ◽  
Size Estimates

Ribbon worms (phylum Nemertea) are among several animal groups that have been overlooked in past studies of genome-size diversity. Here, we report genome-size estimates for eight species of nemerteans, including representatives of the major lineages in the phylum. Genome sizes in these species ranged more than fivefold, and there was some indication of a positive relationship with body size. Somatic endopolyploidy also appears to be common in these animals. Importantly, this study demonstrates that both of the most common methods of genome-size estimation (flow cytometry and Feulgen image analysis densitometry) can be used to assess genome size in ribbon worms, thereby facilitating additional efforts to investigate patterns of variability in nuclear DNA content in this phylum.

Comparative genome size estimation of different life stages of grey mullet, Mugil cephalus Linnaeus, 1758 by flow cytometry

2021 ◽  
Author(s):  
Jani Angel J. Raymond ◽  
Mudagandur Shashi Shekhar ◽  
Vinaya Kumar Katneni ◽  
Ashok Kumar Jangham ◽  
Sudheesh Kommu Prabhudas ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Genome Size ◽  
Mugil Cephalus ◽  
Life Stages ◽  
Size Estimation ◽  
Grey Mullet ◽  
Comparative Genome

scholarly journals Genome Sequence of Clostridium botulinum Strain Adk2012 Associated with a Foodborne Botulinum Case in Tottori, Japan, in 2012

2017 ◽  
Vol 5 (34) ◽  
Author(s):  
Hiroshi Asakura ◽  
Shiori Yamamoto ◽  
Yoshika Momose ◽  
Haru Kato ◽  
Masaaki Iwaki ◽  
...  
Keyword(s):  
Genome Size ◽  
Genome Sequence ◽  
Clostridium Botulinum ◽  
Draft Genome ◽  
Draft Genome Sequence ◽  
Content Type ◽  
Foodborne Botulism

ABSTRACT We report here a draft genome sequence of Clostridium botulinum Adk2012 responsible for a foodborne botulism case that occurred in Tottori, Japan, in 2012. Its genome size was 2,904,173 bp, with 46 rRNAs and 54 tRNAs, at a coverage of 14.5×.

scholarly journals Draft Genome Sequence of a Red Basidiomycete Yeast, Symmetrospora coprosmae Strain UCD350, Isolated from Soil in Ireland

2019 ◽  
Vol 8 (44) ◽  
Author(s):  
Jameela Almasoud ◽  
Laoise McArdle ◽  
Ryan Henne ◽  
Karen Mathews ◽  
Ísla O’Connor ◽  
...  
Keyword(s):  
Genome Size ◽  
Genome Sequence ◽  
Draft Genome ◽  
Draft Genome Sequence ◽  
Content Type ◽  
Red Yeast

Symmetrospora coprosmae is a red yeast from the subphylum Pucciniomycotina in the phylum Basidiomycota. Here, we present the first genome sequence of S. coprosmae strain UCD350, from an isolate collected from soil in Ireland. The genome size is 20.2 Mb.

scholarly journals First draft genome of loach (Orenectus shuilongensis; Cypriniformes: Nemacheilidae) provide insights into the evolution of cavefish

2021 ◽  
Author(s):  
Zhijin Liu ◽  
Xuekun Qian ◽  
Ziming Wang ◽  
Huamei Wen ◽  
Ling Han ◽  
...  
Keyword(s):  
Single Molecule ◽  
Genome Assembly ◽  
Eye Development ◽  
Draft Genome ◽  
Evolutionary Process ◽  
Integrated Approach ◽  
Sequencing Data ◽  
Retina Development ◽  
Draft Genome Assembly ◽  
Surface Dwelling

Abstract BcakgroundLoaches of the superfamily Cobitoidea (Cypriniformes, Nemacheilidae) are small elongated bottom-dwelling freshwater fishes with several barbels near the mouth. The genus Oreonectes with 18 currently recognized species contains representatives for all three key stages of the evolutionary process (a surface-dwelling lifestyle, facultative cave persistence, and permanent cave dwelling). Some Oreonectes species show typical cave dwelling-related traits, such as partial or complete leucism and regression of the eyes, rendering them as suitable study objects of micro-evolution. Genome information of Oreonectes species is therefore an indispensable resource for research into the evolution of cavefishes.ResultsHere we assembled the genome sequence of O. shuilongensis, a surface-dwelling species, using an integrated approach that combined PacBio single-molecule real-time sequencing and Illumina X-ten paired-end sequencing. Based on in total 50.9 Gb of sequencing data, our genome assembly from Canu and Pilon spans approximately 515.64 Mb (estimated coverage of 100 ×), containing 803 contigs with N50 values of 5.58 Mb. 25,247 protein-coding genes were predicted, of which 95.65% have been functionally annotated. We also performed genome re-sequencing of three additional cave-dwelling Oreonectes fishes. Twenty-nine pseudogenes annotated using DAVID showed significant enrichment for the GO terms of “eye development” and “retina development in camera-type eye”. It is presumed that these pseudogenes might lead to eye degeneration of semi/complete cave-dwelling Oreonectes species. Furthermore, Mc1r (melanocortin-1 receptor) is a pseudogenization by a deletion in O. daqikongensis, likely blocking biosynthesis of melanin and leading to the albino phenotype.ConclusionsWe here report the first draft genome assembly of Oreonectes fishes, which is also the first genome reference for Cobitidea fishes. Pseudogenization of genes related to body color and eye development may be responsible for loss of pigmentation and vision deterioration in cave-dwelling species. This genome assembly will contribute to the study of the evolution and adaptation of fishes within Oreonectes and beyond (Cobitidea).

Sign in / Sign up

Export Citation Format

Share Document