A chromosome‐level genome assembly of Brachymystax lenok tsinlingensis provides new insights into salmonids evolution

The salmonid-specific fourth vertebrate whole-genome duplication (Ss4R) occurred ~80 million years ago in the ancestor of all salmonids and provides a unique opportunity to study the evolutionary history of the duplicated genome. Study of the genome of Brachymystax lenok tsinlingensis might be particularly insightful given that this is the only Brachymystax species with a published salmonid genome. Here, we present a high-quality chromosome-level genome assembly for B. l. tsinlingensis and found that the salmonids have a unique GC content and codon usage, have undergone a whole-genome duplication event and a burst of transposon-mediated repeat expansion, have a slower evolutionary rate, and possess specific expanded gene families and unique positively selected genes. Generally, the B. l. tsinlingensis genome could provide a valuable reference for the study of other salmonids as well as aid the conservation of this endangered species.

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Chromosome-level genome assembly of Ophiorrhiza pumila reveals the evolution of camptothecin biosynthesis

Nature Communications ◽

10.1038/s41467-020-20508-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Amit Rai ◽

Hideki Hirakawa ◽

Ryo Nakabayashi ◽

Shinji Kikuchi ◽

Koki Hayashi ◽

...

Keyword(s):

Genome Assembly ◽

Whole Genome Duplication ◽

Experimental Validation ◽

Genome Duplication ◽

Indole Alkaloids ◽

Whole Genome ◽

Comparative Genome Analysis ◽

Plant Genomes ◽

Genome Triplication ◽

Chromosome Level

AbstractPlant genomes remain highly fragmented and are often characterized by hundreds to thousands of assembly gaps. Here, we report chromosome-level reference and phased genome assembly of Ophiorrhiza pumila, a camptothecin-producing medicinal plant, through an ordered multi-scaffolding and experimental validation approach. With 21 assembly gaps and a contig N50 of 18.49 Mb, Ophiorrhiza genome is one of the most complete plant genomes assembled to date. We also report 273 nitrogen-containing metabolites, including diverse monoterpene indole alkaloids (MIAs). A comparative genomics approach identifies strictosidine biogenesis as the origin of MIA evolution. The emergence of strictosidine biosynthesis-catalyzing enzymes precede downstream enzymes’ evolution post γ whole-genome triplication, which occurred approximately 110 Mya in O. pumila, and before the whole-genome duplication in Camptotheca acuminata identified here. Combining comparative genome analysis, multi-omics analysis, and metabolic gene-cluster analysis, we propose a working model for MIA evolution, and a pangenome for MIA biosynthesis, which will help in establishing a sustainable supply of camptothecin.

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Giant African snail genomes provide insights into molluscan whole-genome duplication and aquatic-terrestrial transition

10.1101/2020.02.02.930693 ◽

2020 ◽

Cited By ~ 2

Author(s):

Conghui Liu ◽

Yuwei Ren ◽

Zaiyuan Li ◽

Qi Hu ◽

Lijuan Yin ◽

...

Keyword(s):

Whole Genome Duplication ◽

Genome Duplication ◽

Terrestrial Ecosystems ◽

Gene Families ◽

Gene Clusters ◽

Immune Defense ◽

Whole Genome ◽

Genomic Plasticity ◽

Ecological Adaptability ◽

Chromosome Level

AbstractWhole-genome duplication (WGD) has been observed across a wide variety of eukaryotic groups, contributing to evolutionary diversity and environmental adaptability. Mollusks are the second largest group of animals, and are among the organisms that have successfully adapted to the nonmarine realm through aquatic-terrestrial (A-T) transition, and no comprehensive research on WGD has been reported in this group. To explore WGD and the A-T transition in Mollusca, we assembled a chromosome-level reference genome for the giant African snail Achatina immaculata, a global invasive species, and compared the genomes of two giant African snails (A. immaculata and Achatina fulica) to the other available mollusk genomes. The chromosome-level macrosynteny, colinearity blocks, Ks peak and Hox gene clusters collectively suggested the occurrence of a WGD event shared by A. immaculata and A. fulica. The estimated timing of this WGD event (∼70 MYA) was close to the speciation age of the Sigmurethra-Orthurethra (within Stylommatophora) lineage and the Cretaceous-Tertiary (K-T) mass extinction, indicating that the WGD reported herein may have been a common event shared by all Sigmurethra-Orthurethra species and could have conferred ecological adaptability and genomic plasticity allowing the survival of the K-T extinction. Based on macrosynteny, we deduced an ancestral karyotype containing 8 conserved clusters for the Gastropoda-Bivalvia lineage. To reveal the mechanism of WGD in shaping adaptability to terrestrial ecosystems, we investigated gene families related to the respiration, aestivation and immune defense of giant African snails. Several mucus-related gene families expanded early in the Stylommatophora lineage, functioning in water retention, immune defense and wound healing. The hemocyanins, PCK and FBP families were doubled and retained after WGD, enhancing the capacity for gas exchange and glucose homeostasis in aestivation. After the WGD, zinc metalloproteinase genes were highly tandemly duplicated to protect tissue against ROS damage. This evidence collectively suggests that although the WGD may not have been the direct driver of the A-T transition, it provided an important legacy for the terrestrial adaptation of the giant African snail.

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A chromosome-level genome of the spider Trichonephila antipodiana reveals the genetic basis of its polyphagy and evidence of an ancient whole-genome duplication event

GigaScience ◽

10.1093/gigascience/giab016 ◽

2021 ◽

Vol 10 (3) ◽

Author(s):

Zheng Fan ◽

Tao Yuan ◽

Piao Liu ◽

Lu-Yu Wang ◽

Jian-Feng Jin ◽

...

Keyword(s):

Whole Genome Duplication ◽

Large Scale ◽

Hox Genes ◽

Genome Duplication ◽

Duplication Event ◽

Whole Genome ◽

High Quality ◽

Genome Duplication Event ◽

Whole Genome Duplication Event ◽

Chromosome Level

Abstract Background The spider Trichonephila antipodiana (Araneidae), commonly known as the batik golden web spider, preys on arthropods with body sizes ranging from ∼2 mm in length to insects larger than itself (>20‒50 mm), indicating its polyphagy and strong dietary detoxification abilities. Although it has been reported that an ancient whole-genome duplication event occurred in spiders, lack of a high-quality genome has limited characterization of this event. Results We present a chromosome-level T. antipodiana genome constructed on the basis of PacBio and Hi-C sequencing. The assembled genome is 2.29 Gb in size with a scaffold N50 of 172.89 Mb. Hi-C scaffolding assigned 98.5% of the bases to 13 pseudo-chromosomes, and BUSCO completeness analysis revealed that the assembly included 94.8% of the complete arthropod universal single-copy orthologs (n = 1,066). Repetitive elements account for 59.21% of the genome. We predicted 19,001 protein-coding genes, of which 96.78% were supported by transcriptome-based evidence and 96.32% matched protein records in the UniProt database. The genome also shows substantial expansions in several detoxification-associated gene families, including cytochrome P450 mono-oxygenases, carboxyl/cholinesterases, glutathione-S-transferases, and ATP-binding cassette transporters, reflecting the possible genomic basis of polyphagy. Further analysis of the T. antipodiana genome architecture reveals an ancient whole-genome duplication event, based on 2 lines of evidence: (i) large-scale duplications from inter-chromosome synteny analysis and (ii) duplicated clusters of Hox genes. Conclusions The high-quality T. antipodiana genome represents a valuable resource for spider research and provides insights into this species’ adaptation to the environment.

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The genome of the venomous snail Lautoconus ventricosus sheds light on the origin of conotoxin diversity

GigaScience ◽

10.1093/gigascience/giab037 ◽

2021 ◽

Vol 10 (5) ◽

Cited By ~ 1

Author(s):

José Ramón Pardos-Blas ◽

Iker Irisarri ◽

Samuel Abalde ◽

Carlos M L Afonso ◽

Manuel J Tenorio ◽

...

Keyword(s):

Whole Genome Duplication ◽

Genome Duplication ◽

Duplication Event ◽

Pomacea Canaliculata ◽

Whole Genome ◽

Genome Duplication Event ◽

Whole Genome Duplication Event ◽

Venomous Animals ◽

Genes Encoding ◽

Chromosome Level

Abstract Background Venoms are deadly weapons to subdue prey or deter predators that have evolved independently in many animal lineages. The genomes of venomous animals are essential to understand the evolutionary mechanisms involved in the origin and diversification of venoms. Results Here, we report the chromosome-level genome of the venomous Mediterranean cone snail, Lautoconus ventricosus (Caenogastropoda: Conidae). The total size of the assembly is 3.59 Gb; it has high contiguity (N50 = 93.53 Mb) and 86.6 Mb of the genome assembled into the 35 largest scaffolds or pseudochromosomes. On the basis of venom gland transcriptomes, we annotated 262 complete genes encoding conotoxin precursors, hormones, and other venom-related proteins. These genes were scattered in the different pseudochromosomes and located within repetitive regions. The genes encoding conotoxin precursors were normally structured into 3 exons, which did not necessarily coincide with the 3 structural domains of the corresponding proteins. Additionally, we found evidence in the L. ventricosus genome for a past whole-genome duplication event by means of conserved gene synteny with the Pomacea canaliculata genome, the only one available at the chromosome level within Caenogastropoda. The whole-genome duplication event was further confirmed by the presence of a duplicated hox gene cluster. Key genes for gastropod biology including those encoding proteins related to development, shell formation, and sex were located in the genome. Conclusions The new high-quality L. ventricosus genome should become a reference for assembling and analyzing new gastropod genomes and will contribute to future evolutionary genomic studies among venomous animals.

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Phylogenetic Analysis of T-Box Genes Demonstrates the Importance of Amphioxus for Understanding Evolution of the Vertebrate Genome

Genetics ◽

10.1093/genetics/156.3.1249 ◽

2000 ◽

Vol 156 (3) ◽

pp. 1249-1257

Author(s):

Ilya Ruvinsky ◽

Lee M Silver ◽

Jeremy J Gibson-Brown

Keyword(s):

Phylogenetic Analysis ◽

Whole Genome Duplication ◽

Genome Duplication ◽

Gene Families ◽

Vertebrate Evolution ◽

Whole Genome ◽

Vertebrate Genome ◽

T Box ◽

Genetic Complexity ◽

History Of

Abstract The duplication of preexisting genes has played a major role in evolution. To understand the evolution of genetic complexity it is important to reconstruct the phylogenetic history of the genome. A widely held view suggests that the vertebrate genome evolved via two successive rounds of whole-genome duplication. To test this model we have isolated seven new T-box genes from the primitive chordate amphioxus. We find that each amphioxus gene generally corresponds to two or three vertebrate counterparts. A phylogenetic analysis of these genes supports the idea that a single whole-genome duplication took place early in vertebrate evolution, but cannot exclude the possibility that a second duplication later took place. The origin of additional paralogs evident in this and other gene families could be the result of subsequent, smaller-scale chromosomal duplications. Our findings highlight the importance of amphioxus as a key organism for understanding evolution of the vertebrate genome.

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Comparative Mapping Between Coho Salmon (Oncorhynchus kisutch) and Three Other Salmonids Suggests a Role for Chromosomal Rearrangements in the Retention of Duplicated Regions Following a Whole Genome Duplication Event

G3 Genes|Genome|Genetics ◽

10.1534/g3.114.012294 ◽

2014 ◽

Vol 4 (9) ◽

pp. 1717-1730 ◽

Cited By ~ 37

Author(s):

M. Kodama ◽

M. S. O. Brieuc ◽

R. H. Devlin ◽

J. J. Hard ◽

K. A. Naish

Keyword(s):

Comparative Mapping ◽

Whole Genome Duplication ◽

Genome Duplication ◽

Coho Salmon ◽

Chromosomal Rearrangements ◽

Oncorhynchus Kisutch ◽

Duplication Event ◽

Whole Genome ◽

Genome Duplication Event ◽

Whole Genome Duplication Event

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Rapid Diversification of FoxP2 in Teleosts through Gene Duplication in the Teleost-Specific Whole Genome Duplication Event

PLoS ONE ◽

10.1371/journal.pone.0083858 ◽

2013 ◽

Vol 8 (12) ◽

pp. e83858 ◽

Cited By ~ 2

Author(s):

Xiaowei Song ◽

Yajun Wang ◽

Yezhong Tang

Keyword(s):

Gene Duplication ◽

Whole Genome Duplication ◽

Genome Duplication ◽

Duplication Event ◽

Whole Genome ◽

Genome Duplication Event ◽

Whole Genome Duplication Event ◽

Rapid Diversification

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Comparative Inference of Duplicated Genes Produced by Polyploidization in Soybean Genome

International Journal of Genomics ◽

10.1155/2013/275616 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4

Author(s):

Yanmei Yang ◽

Jinpeng Wang ◽

Jianyong Di

Keyword(s):

Statistical Analysis ◽

Whole Genome Duplication ◽

Genome Duplication ◽

Duplication Event ◽

Plant Evolution ◽

Soybean Genome ◽

Whole Genome ◽

Duplicated Genes ◽

Genome Duplication Event ◽

Scientific Value

Soybean (Glycine max) is one of the most important crop plants for providing protein and oil. It is important to investigate soybean genome for its economic and scientific value. Polyploidy is a widespread and recursive phenomenon during plant evolution, and it could generate massive duplicated genes which is an important resource for genetic innovation. Improved sequence alignment criteria and statistical analysis are used to identify and characterize duplicated genes produced by polyploidization in soybean. Based on the collinearity method, duplicated genes by whole genome duplication account for 70.3% in soybean. From the statistical analysis of the molecular distances between duplicated genes, our study indicates that the whole genome duplication event occurred more than once in the genome evolution of soybean, which is often distributed near the ends of chromosomes.

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A chromosome-level genome assembly of the oriental river prawn, Macrobrachium nipponense

GigaScience ◽

10.1093/gigascience/giaa160 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Shubo Jin ◽

Chao Bian ◽

Sufei Jiang ◽

Kai Han ◽

Yiwei Xiong ◽

...

Keyword(s):

Genome Assembly ◽

Evolutionary Biology ◽

Sex Differentiation ◽

Duplication Event ◽

Whole Genome ◽

Genome Duplication Event ◽

Protein Coding ◽

Macrobrachium Nipponense ◽

Oriental River Prawn ◽

Chromosome Level

Abstract Background The oriental river prawn, Macrobrachium nipponense, is an economically important shrimp in China. Male prawns have higher commercial value than females because the former grow faster and reach larger sizes. It is therefore important to reveal sex-differentiation and development mechanisms of the oriental river prawn to enable genetic improvement. Results We sequenced 293.3 Gb of raw Illumina short reads and 405.7 Gb of Pacific Biosciences long reads. The final whole-genome assembly of the Oriental river prawn was ∼4.5 Gb in size, with predictions of 44,086 protein-coding genes. A total of 49 chromosomes were determined, with an anchor ratio of 94.7% and a scaffold N50 of 86.8 Mb. A whole-genome duplication event was deduced to have happened 109.8 million years ago. By integration of genome and transcriptome data, 21 genes were predicted as sex-related candidate genes. Conclusion The first high-quality chromosome-level genome assembly of the oriental river prawn was obtained. These genomic data, along with transcriptome sequences, are essential for understanding sex-differentiation and development mechanisms in the oriental river prawn, as well as providing genetic resources for in-depth studies on developmental and evolutionary biology in arthropods.

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