scholarly journals ONT-based draft genome assembly and annotation of Alternaria atra

Author(s):  
Bhawna Bonthala ◽  
Corinn Sophia Small ◽  
Maximilian Anton Lutz ◽  
Alexander Graf ◽  
Stefan Krebs ◽  
...  

Species of Alternaria (phylum Ascomycota, family Pleosporaceae) are known as serious plant pathogens, causing major losses on a wide range of crops. Alternaria atra (Preuss) Woudenb. & Crous (previously known as Ulocladium atrum) can grow as a saprophyte on many hosts and causes Ulocladium blight on potato. It has been reported that it can also be used as a biocontrol agent against a.o. Botrytis cinerea Here we present a scaffold-level reference genome assembly for A. atra. The assembly contains 43 scaffolds with a total length of 39.62 Mbp, with scaffold N50 of 3,893,166 bp , L50 of 4 and the longest 10 scaffolds containing 89.9% of the assembled data. RNA Seq-guided, gene prediction using BRAKER resulted in 12,173 protein-coding genes with their functional annotation. This first high-quality reference genome assembly and annotation for A. Atra can be used as a resource for studying evolution in the highly complicated Alternaria genus and might help understand the mechanisms defining its role as pathogen or biocontrol agent.

2020 ◽  
Vol 33 (7) ◽  
pp. 880-883
Author(s):  
Stefan Kusch ◽  
Heba M. M. Ibrahim ◽  
Catherine Zanchetta ◽  
Celine Lopez-Roques ◽  
Cecile Donnadieu ◽  
...  

The fungus Myriosclerotinia sulcatula is a close relative of the notorious polyphagous plant pathogens Botrytis cinerea and Sclerotinia sclerotiorum but exhibits a host range restricted to plants from the Carex genus (Cyperaceae family). To date, there are no genomic resources available for fungi in the Myriosclerotinia genus. Here, we present a chromosome-scale reference genome assembly for M. sulcatula. The assembly contains 24 contigs with a total length of 43.53 Mbp, with scaffold N50 of 2,649.7 kbp and N90 of 1,133.1 kbp. BRAKER-predicted gene models were manually curated using WebApollo, resulting in 11,275 protein-coding genes that we functionally annotated. We provide a high-quality reference genome assembly and annotation for M. sulcatula as a resource for studying evolution and pathogenicity in fungi from the Sclerotiniaceae family.


2018 ◽  
Vol 6 (16) ◽  
pp. e00265-18 ◽  
Author(s):  
Stewart T. G. Burgess ◽  
Kathryn Bartley ◽  
Edward J. Marr ◽  
Harry W. Wright ◽  
Robert J. Weaver ◽  
...  

ABSTRACT Sheep scab, caused by infestation with Psoroptes ovis, is highly contagious, results in intense pruritus, and represents a major welfare and economic concern. Here, we report the first draft genome assembly and gene prediction of P. ovis based on PacBio de novo sequencing. The ∼63.2-Mb genome encodes 12,041 protein-coding genes.


Genes ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 708 ◽  
Author(s):  
Julien Alban Nguinkal ◽  
Ronald Marco Brunner ◽  
Marieke Verleih ◽  
Alexander Rebl ◽  
Lidia de los Ríos-Pérez ◽  
...  

The pikeperch (Sander lucioperca) is a fresh and brackish water Percid fish natively inhabiting the northern hemisphere. This species is emerging as a promising candidate for intensive aquaculture production in Europe. Specific traits like cannibalism, growth rate and meat quality require genomics based understanding, for an optimal husbandry and domestication process. Still, the aquaculture community is lacking an annotated genome sequence to facilitate genome-wide studies on pikeperch. Here, we report the first highly contiguous draft genome assembly of Sander lucioperca. In total, 413 and 66 giga base pairs of DNA sequencing raw data were generated with the Illumina platform and PacBio Sequel System, respectively. The PacBio data were assembled into a final assembly size of ~900 Mb covering 89% of the 1,014 Mb estimated genome size. The draft genome consisted of 1966 contigs ordered into 1,313 scaffolds. The contig and scaffold N50 lengths are 3.0 Mb and 4.9 Mb, respectively. The identified repetitive structures accounted for 39% of the genome. We utilized homologies to other ray-finned fishes, and ab initio gene prediction methods to predict 21,249 protein-coding genes in the Sander lucioperca genome, of which 88% were functionally annotated by either sequence homology or protein domains and signatures search. The assembled genome spans 97.6% and 96.3% of Vertebrate and Actinopterygii single-copy orthologs, respectively. The outstanding mapping rate (99.9%) of genomic PE-reads on the assembly suggests an accurate and nearly complete genome reconstruction. This draft genome sequence is the first genomic resource for this promising aquaculture species. It will provide an impetus for genomic-based breeding studies targeting phenotypic and performance traits of captive pikeperch.


2021 ◽  
Author(s):  
Roger Huerlimann ◽  
Jeff A Cowley ◽  
Nicholas M Wade ◽  
Yinan Wang ◽  
Naga Kasinadhuni ◽  
...  

Shrimp are a valuable aquaculture species globally; however, disease remains a major hindrance to shrimp aquaculture sustainability and growth. Mechanisms mediated by endogenous viral elements (EVEs) have been proposed as a means by which shrimp that encounter a new virus start to accommodate rather than succumb to infection over time. However, evidence on the nature of such EVEs and how they mediate viral accommodation is limited. More extensive genomic data on Penaeid shrimp from different geographical locations should assist in exposing the diversity of EVEs. In this context, reported here is a PacBio Sequel-based draft genome assembly of an Australian black tiger shrimp (Penaeus monodon) inbred for one generation. The 1.89 Gbp draft genome is comprised of 31,922 scaffolds (N50: 496,398 bp) covering 85.9% of the projected genome size. The genome repeat content (61.8% with 30% representing simple sequence repeats) is almost the highest identified for any species. The functional annotation identified 35,517 gene models, of which 25,809 were protein-coding and 17,158 were annotated using interproscan. Scaffold scanning for specific EVEs identified an element comprised of a 9,045 bp stretch of repeated, inverted and jumbled genome fragments of Infectious hypodermal and hematopoietic necrosis virus (IHHNV) bounded by a repeated 591/590 bp host sequence. As only near complete linear ~4 kb IHHNV genomes have been found integrated in the genome of P. monodon previously, its discovery has implications regarding the validity of PCR tests designed to specifically detect such linear EVE types. The existence of conjoined inverted IHHNV genome fragments also provides a means by which hairpin dsRNAs could be expressed and processed by the shrimp RNA interference (RNAi) machinery.


2020 ◽  
Vol 12 (7) ◽  
pp. 1074-1079 ◽  
Author(s):  
Ruihao Shu ◽  
Jihong Zhang ◽  
Qian Meng ◽  
Huan Zhang ◽  
Guiling Zhou ◽  
...  

Abstract Ophiocordyceps sinensis (Berk.) is an entomopathogenic fungus endemic to the Qinghai-Tibet Plateau. It parasitizes and mummifies the underground ghost moth larvae, then produces a fruiting body. The fungus-insect complex, called Chinese cordyceps or “DongChongXiaCao,” is not only a valuable traditional Chinese medicine, but also a major source of income for numerous Himalayan residents. Here, taking advantage of rapid advances in single-molecule sequencing, we assembled a highly contiguous genome assembly of O. sinensis. The assembly of 23 contigs was ∼110.8 Mb with a N50 length of 18.2 Mb. We used RNA-seq and homologous protein sequences to identify 8,916 protein-coding genes in the IOZ07 assembly. Moreover, 63 secondary metabolite gene clusters were identified in the improved assembly. The improved assembly and genome features described in this study will further inform the evolutionary study and resource utilization of Chinese cordyceps.


Author(s):  
Qiye Li ◽  
Qunfei Guo ◽  
Yang Zhou ◽  
Huishuang Tan ◽  
Terry Bertozzi ◽  
...  

AbstractAmphibian genomes are usually challenging to assemble due to large genome size and high repeat content. The Limnodynastidae is a family of frogs native to Australia, Tasmania and New Guinea. As an anuran lineage that successfully diversified on the Australian continent, it represents an important lineage in the amphibian tree of life but lacks reference genomes. Here we sequenced and annotated the genome of the eastern banjo frog Limnodynastes dumerilii dumerilii to fill this gap. The total length of the genome assembly is 2.38 Gb with a scaffold N50 of 285.9 kb. We identified 1.21 Gb of non-redundant sequences as repetitive elements and annotated 24,548 protein-coding genes in the assembly. BUSCO assessment indicated that more than 94% of the expected vertebrate genes were present in the genome assembly and the gene set. We anticipate that this annotated genome assembly will advance the future study of anuran phylogeny and amphibian genome evolution.


GigaScience ◽  
2019 ◽  
Vol 8 (8) ◽  
Author(s):  
Xin Jiang ◽  
Qian Zhang ◽  
Yaoguo Qin ◽  
Hang Yin ◽  
Siyu Zhang ◽  
...  

AbstractBackgroundSitobion miscanthi is an ideal model for studying host plant specificity, parthenogenesis-based phenotypic plasticity, and interactions between insects and other species of various trophic levels, such as viruses, bacteria, plants, and natural enemies. However, the genome information for this species has not yet to be sequenced and published. Here, we analyzed the entire genome of a parthenogenetic female aphid colony using Pacific Biosciences long-read sequencing and Hi-C data to generate chromosome-length scaffolds and a highly contiguous genome assembly.ResultsThe final draft genome assembly from 33.88 Gb of raw data was ∼397.90 Mb in size, with a 2.05 Mb contig N50. Nine chromosomes were further assembled based on Hi-C data to a 377.19 Mb final size with a 36.26 Mb scaffold N50. The identified repeat sequences accounted for 26.41% of the genome, and 16,006 protein-coding genes were annotated. According to the phylogenetic analysis, S. miscanthi is closely related to Acyrthosiphon pisum, with S. miscanthi diverging from their common ancestor ∼25.0–44.9 million years ago.ConclusionsWe generated a high-quality draft of the S. miscanthi genome. This genome assembly should help promote research on the lifestyle and feeding specificity of aphids and their interactions with each other and species at other trophic levels. It can serve as a resource for accelerating genome-assisted improvements in insecticide-resistant management and environmentally safe aphid management.


2019 ◽  
Vol 8 (36) ◽  
Author(s):  
Duy An Duong ◽  
Patricia Espinosa-Artiles ◽  
Rousel A. Orozco ◽  
István Molnár ◽  
S. Patricia Stock

Photorhabdus luminescens subsp. sonorensis strain Caborca is an entomopathogenic bacterium with a dual lifestyle, namely, as a mutualist of the Heterorhabditis sonorensis nematode and a pathogen to a wide range of insect species. The genome assembly, in 231 contigs, is 5.2 Mbp long and includes 25 putative gene clusters for secondary metabolism.


2021 ◽  
Vol 11 (2) ◽  
Author(s):  
Robert C Lee ◽  
Lina Farfan-Caceres ◽  
Johannes W Debler ◽  
Angela H Williams ◽  
Robert A Syme ◽  
...  

Abstract Ascochyta lentis causes ascochyta blight in lentil (Lens culinaris Medik.) and yield loss can be as high as 50%. With careful agronomic management practices, fungicide use, and advances in breeding resistant lentil varieties, disease severity and impact to farmers have been largely controlled. However, evidence from major lentil producing countries, Canada and Australia, suggests that A. lentis isolates can change their virulence profile and level of aggressiveness over time and under different selection pressures. In this paper, we describe the first genome assembly for A. lentis for the Australian isolate Al4, through the integration of data from Illumina and PacBio SMRT sequencing. The Al4 reference genome assembly is almost 42 Mb in size and encodes 11,638 predicted genes. The Al4 genome comprises 21 full-length and gapless chromosomal contigs and two partial chromosome contigs each with one telomere. We predicted 31 secondary metabolite clusters, and 38 putative protein effectors, many of which were classified as having an unknown function. Comparison of A. lentis genome features with the recently published reference assembly for closely related A. rabiei show that genome synteny between these species is highly conserved. However, there are several translocations and inversions of genome sequence. The location of secondary metabolite clusters near transposable element and repeat-rich genomic regions was common for A. lentis as has been reported for other fungal plant pathogens.


2021 ◽  
Author(s):  
Alison L Gould ◽  
James B Henderson ◽  
Athena W Lam

The bioluminescent symbiosis between the sea urchin cardinalfish Siphamia tubifer (Kurtiformes: Apogonidae) and the luminous bacterium Photobacterium mandapamensis is an emerging vertebrate-bacteria model for the study of microbial symbiosis. However, there is little genetic data available for the host fish, limiting the scope of potential research that can be carried out with this association. In this study, we present a chromosomal-level genome assembly of S. tubifer using a combination of PacBio HiFi sequencing and Hi-C technologies. The final genome assembly was 1.2 Gb distributed on 23 chromosomes and contained 32,365 protein coding genes with a BUSCO completeness score of 99%. A comparison of the S. tubifer genome to that of another non-luminous cardinalfish revealed a high degree of synteny, whereas a similar comparison to a more distant relative in the Gobiiformes order revealed a fusion of two chromosomes in the cardinalfish genomes. An additional comparison of orthologous clusters among these three genomes revealed a set of 710 clusters that were unique to S. tubifer in which 23 GO pathways were significantly enriched, including several relating to host-microbe interactions and one involved in visceral muscle development, which could be related to the musculature involved in the gut-associated light organ of S. tubifer. We also assembled the complete mitogenome of S. tubifer and discovered both an inversion in the WANCY tRNA gene region resulting in a WACNY gene order as well as heteroplasmy in the length of the control region for this individual. A phylogenetic analysis based on the whole mitochondrial genome indicated that S. tubifer is divergent from the rest of the cardinalfish family, bringing up questions of the involvement of the bioluminescent symbiosis in the initial divergence of the ancestral Siphamia species. This draft genome assembly of S. tubifer will enable future studies investigating the evolution of bioluminescence in fishes as well as candidate genes involved in the symbiosis and will provide novel opportunities to use this system as a vertebrate-bacteria model for symbiosis research.


Sign in / Sign up

Export Citation Format

Share Document