• 원예과학기술지
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• 제32권4호
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• pp.535-543
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• 2014

Backcross breeding is the method most commonly used to introgress new traits into elite lines. Conventional backcross breeding requires at least 4-5 generations to recover the genomic background of the recurrent parent. Marker-assisted backcrossing (MABC) represents a new breeding approach that can substantially reduce breeding time and cost. For successful MABC, highly polymorphic markers with known positions in each chromosome are essential. Single nucleotide polymorphism (SNP) markers have many advantages over other marker systems for MABC due to their high abundance and amenability to genotyping automation. To facilitate MABC in hot pepper (Capsicum annuum), we utilized expressed sequence tags (ESTs) to develop SNP markers in this study. For SNP identification, we used Bukang $F_1$-hybrid pepper ESTs to prepare a reference sequence through de novo assembly. We performed large-scale transcriptome sequencing of eight accessions using the Illumina Genome Analyzer (IGA) IIx platform by Solexa, which generated small sequence fragments of about 90-100 bp. By aligning each contig to the reference sequence, 58,151 SNPs were identified. After filtering for polymorphism, segregation ratio, and lack of proximity to other SNPS or exon/intron boundaries, a total of 1,910 putative SNPs were chosen and positioned to a pepper linkage map. We further selected 412 SNPs evenly distributed on each chromosome and primers were designed for high throughput SNP assays and tested using a genetic diversity panel of 27 Capsicum accessions. The SNP markers clearly distinguished each accession. These results suggest that the SNP marker set developed in this study will be valuable for MABC, genetic mapping, and comparative genome analysis.

• Journal of Plant Biotechnology
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• 제46권4호
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• pp.274-281
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• 2019

Pistacia chinensis Bunge has not only been used as a medicinal plant to treat various illnesses but its young shoots and leaves have also been used as vegetables. In addition, P. chinensis is used as a rootstock for Pistacia vera (pistachio). Here, the transcriptome of P. chinensis was sequenced to enrich genetic resources and identify secondary metabolite biosynthetic pathways using Illumina RNA-seq methods. De novo assembly resulted in 18,524 unigenes with an average length of 873 bp from 19 million RNA-seq reads. A Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation tool assigned KO (KEGG orthology) numbers to 6,553 (36.2%) unigenes, among which 4,061 unigenes were mapped into 391 different metabolic pathways. For terpenoid backbone and carotenoid biosynthesis pathways, 44 and 22 unigenes encode enzymes corresponding to 30 and 16 entries, respectively. Twenty-two unigenes encode proteins for 16 entries of the carotenoid biosynthesis pathway. As for the phenylpropanoid and flavonoid biosynthesis pathways, 63 and 24 unigenes were homologous to 17 and 14 entry proteins, respectively. Mining of simple sequence repeat identified 2,599 simple sequence repeats from P. chinensis unigenes. The results of the present study provide a valuable resource for in-depth studies on comparative and functional genomics to unravel the underlying mechanisms of the medicinal properties of Pistacia L.

• Journal of Plant Biotechnology
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• 제43권3호
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• pp.302-310
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• 2016

A study aimed at identifying putative drought responsive genes that confer tolerance to water stress deficit in tea plants was conducted in a 'rain-out shelter' using potted plants. Eighteen months old drought tolerant and susceptible tea cultivars were each separately exposed to water stress or control conditions of 18 or 34% soil moisture content, respectively, for three months. After the treatment period, leaves were harvested from each treatment for isolation of RNA and cDNA synthesis. The cDNA libraries were sequenced on Roche 454 high-throughput pyrosequencing platform to produce 232,853 reads. After quality control, the reads were assembled into 460 long transcripts (contigs). The annotated contigs showed similarity with proteins in the Arabidopsis thaliana proteome. Heat shock proteins (HSP70), superoxide dismutase (SOD), catalase (cat), peroxidase (PoX), calmodulinelike protein (Cam7) and galactinol synthase (Gols4) droughtrelated genes were shown to be regulated differently in tea plants exposed to water stress. HSP70 and SOD were highly expressed in the drought tolerant cultivar relative to the susceptible cultivar under drought conditions. The genes and pathways identified suggest efficient regulation leading to active adaptation as a basal defense response against water stress deficit by tea. The knowledge generated can be further utilized to better understand molecular mechanisms underlying stress tolerance in tea.

• Journal of Ginseng Research
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• 제44권2호
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• pp.312-320
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• 2020

Background: Ginseng (Panax ginseng Meyer) is an essential source of pharmaceuticals and functional foods. Ginseng productivity has been compromised by high light (HL) stress, which is one of the major abiotic stresses during the ginseng cultivation period. The genetic improvement for HL tolerance in ginseng could be facilitated by analyzing its genetic and molecular characteristics associated with HL stress. Methods: Genome-wide analysis of gene expression was performed under HL and recovery conditions in 1-year-old Korean ginseng (P. ginseng cv. Chunpoong) using the Illumina HiSeq platform. After de novo assembly of transcripts, we performed expression profiling and identified differentially expressed genes (DEGs). Furthermore, putative functions of identified DEGs were explored using Gene Ontology terms and Kyoto Encyclopedia of Genes and Genome pathway enrichment analysis. Results: A total of 438 highly expressed DEGs in response to HL stress were identified and selected from 29,184 representative transcripts. Among the DEGs, 326 and 114 transcripts were upregulated and downregulated, respectively. Based on the functional analysis, most upregulated and a significant number of downregulated transcripts were related to stress responses and cellular metabolic processes, respectively. Conclusion: Transcriptome profiling could be a strategy to comprehensively elucidate the genetic and molecular mechanisms of HL tolerance and susceptibility. This study would provide a foundation for developing breeding and metabolic engineering strategies to improve the environmental stress tolerance of ginseng.

• Journal of Ginseng Research
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• 제44권1호
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• pp.123-134
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• 2020

Background: The lepidopteran Asiatic corn borer (ACB), Ostrinia furnacalis (Guenee), has caused huge economic losses throughout the Asian-Western Pacific region. Usually, chemical pesticides are used for the control, but excessive use of pesticides has caused great harm. Therefore, the inartificial ecotypic pesticides to ACB are extremely essential. In our previous study, we found that panaxadiol saponins (PDS) can effectively reduce the harm of ACB by causing antifeedant activity. Therefore, it is necessary to reveal the biological molecular changes in ACB and the functionary mechanism of PDS. Methods: We analyzed the global transcription of ACB with different PDS concentration treatment (5 mg/mL, 10 mg/mL, and 25 mg/mL) by high-throughput sequencing and de novo transcriptome assembly method. Results: PDS treatment could cause the changes of many gene expressions which regulate its signal pathways. The genes in peroxisome proliferator-activated receptor (PPAR) signaling pathway were significantly downregulated, and then, the downstream fatty acid degradation pathway had also been greatly affected. Conclusion: Through this experiment, we hypothesized that the occurrence of antifeedant action of ACB is because the PDS brought about the downregulation of FATP and FABP, the key regulators in the PPAR, and the downregulation of FATP and FABP exerts further effects on the expression of SCD-1, ACBP, LPL, SCP-X, and ACO, which leads to the disorder of PPAR signaling pathway and the fatty acid degradation pathway. Not only that, PDS treatment leads to enzyme activity decrease by inhibiting the expression of genes associated with catalytic activity, such as cytochrome P450 and other similar genes.

• Genomics & Informatics
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• 제17권1호
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• pp.5.1-5.9
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• 2019

The chinstrap (Pygoscelis antarcticus) and gentoo (P. papua) penguins are distributed throughout Antarctica and the sub-Antarctic islands. In this study, high-quality de novo assemblies of blood transcriptomes from these penguins were generated using the Illumina MiSeq platform. A total of 22.2 and 21.8 raw reads were obtained from chinstrap and gentoo penguins, respectively. These reads were assembled using the Oases assembly platform and resulted in 26,036 and 21,854 contigs with N50 values of 929 and 933 base pairs, respectively. Functional gene annotations through pathway analyses of the Gene Ontology, EuKaryotic Orthologous Groups, and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were performed for each blood transcriptome, resulting in a similar compositional order between the two transcriptomes. Ortholog comparisons with previously published transcriptomes from the $Ad{\acute{e}}lie$ (P. adeliae) and emperor (Aptenodytes forsteri) penguins revealed that a high proportion of the four penguins' transcriptomes had significant sequence homology. Because blood and tissues of penguins have been used to monitor pollution in Antarctica, immune parameters in blood could be important indicators for understanding the health status of penguins and other Antarctic animals. In the blood transcriptomes, KEGG analyses detected many essential genes involved in the major innate immunity pathways, which are key metabolic pathways for maintaining homeostasis against exogenous infections or toxins. Blood transcriptome studies such as this may be useful for checking the immune and health status of penguins without sacrifice.

• The Plant Pathology Journal
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• 제37권6호
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• pp.619-631
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• 2021

Alfalfa mosaic virus (AMV), an economically important pathogen, is present worldwide with a very wide host range. This work reports for the first time the infection of Vinca minor and Wisteria sinensis with AMV using RNA sequencing and reverse transcription polymerase chain reaction confirmation. De novo assembly and annotating of contigs revealed that RNA1, RNA2, and RNA3 genomic fragments consist of 3,690, 2,636, and 2,057 nucleotides (nt) for IR-VM and 3,690, 2,594, and 2,057 nt for IR-WS. RNA1 and RNA3 segments of IR-VM and IR-WS closely resembled those of the Chinese isolate HZ, with 99.23-99.26% and 98.04-98.09% nt identity, respectively. Their RNA2 resembled that of Canadian isolate CaM and American isolate OH-2-2017, with 97.96-98.07% nt identity. The P2 gene revealed more nucleotide diversity compared with other genes. Genes in the AMV genome were under dominant negative selection during evolution, and the P1 and coat protein (CP) proteins were subject to the strongest and weakest purifying selection, respectively. In the population genetic analysis based on the CP gene sequences, all 107 AMV isolates fell into two main clades (A, B) and isolates of clade A were further divided into three groups with significant subpopulation differentiation. The results indicated moderate genetic variation within and no clear geographic or genetic structure between the studied populations, implying moderate gene flow can play an important role in differentiation and distribution of genetic diversity among populations. Several factors have shaped the genetic structure and diversity of AMV: selection, recombination/reassortment, gene flow, and random processes such as founder effects.

• Parasites, Hosts and Diseases
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• 제61권2호
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• pp.202-209
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• 2023

Lophomonas blattarum is an anaerobic protozoan living in the intestine of cockroaches and house dust mites, with ultramicroscopic characteristics such as the presence of a parabasal body, axial filament, and absence of mitochondria. More than 200 cases of Lophomonas infection of the respiratory tract have been reported worldwide. However, the current diagnosis of such infection depends only on light microscopic morphological findings from respiratory secretions. In this study, we attempted to provide more robust evidence of protozoal infection in an immunocompromised patient with atypical pneumonia, positive for Lophomonas-like protozoal cell forms. A direct search of bronchoalveolar lavage fluid via polymerase chain reaction (PCR), transmission electron microscopy (TEM), and metagenomic next-generation sequencing did not prove the presence of protozoal infection. PCR results were not validated with sufficient rigor, while de novo assembly and taxonomic classification results did not confirm the presence of an unidentified pathogen. The TEM results implied that such protozoal forms in light microscopy are actually non-detached ciliated epithelial cells. After ruling out infectious causes, the patient's final diagnosis was drug-induced pneumonitis. These findings underscore the lack of validation in the previously utilized diagnostic methods, and more evidence in the presence of L. blattarum is required to further prove its pathogenicity.

• Mycobiology
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• 제51권1호
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• pp.36-48
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• 2023

Xanthoria elegans is a lichen symbiosis, that inhabits extreme environments and can absorb UV-B. We reported the de novo sequencing and assembly of X. elegans genome. The whole genome was approximately 44.63 Mb, with a GC content of 40.69%. Genome assembly generated 207 scaffolds with an N50 length of 563,100 bp, N90 length of 122,672 bp. The genome comprised 9,581 genes, some encoded enzymes involved in the secondary metabolism such as terpene, polyketides. To further understand the UV-B absorbing and adaptability to extreme environments mechanisms of X. elegans, we searched the secondary metabolites genes and gene-cluster from the genome using genome-mining and bioinformatics analysis. The results revealed that 7 NR-PKSs, 12 HR-PKSs and 2 hybrid PKS-PKSs from X. elegans were isolated, they belong to Type I PKS (T1PKS) according to the domain architecture; phylogenetic analysis and BGCs comparison linked the putative products to two NR-PKSs and three HR-PKSs, the putative products of two NR-PKSs were emodin xanthrone (most likely parietin) and mycophelonic acid, the putative products of three HR-PKSs were soppilines, (+)-asperlin and macrolactone brefeldin A, respectively. 5 PKSs from X. elegans build a correlation between the SMs carbon skeleton and PKS genes based on the domain architecture, phylogenetic and BGC comparison. Although the function of 16 PKSs remains unclear, the findings emphasize that the genes from X. elegans represent an unexploited source of novel polyketide and utilization of lichen gene resources.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.537-545
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• 2018

본 연구에서는 메밀의 발아초기에 발현되는 전사체의 다양한 정보 수집을 위해 양절메밀과 대관 3-3호의 RNA를 추출하여 전사체 분석을 수행하였다. 제주산 양절메밀과 대관3-3호의 종자 및 발아 후 12, 24, 36시간별로 total RNA를 추출하고, llumina Hiseq 2000 플랫폼을 사용하여 시퀀싱 하였다. SolexaQA package의 DynamicTrim과 LengthsORT 프로그램으로 이용하여 raw 데이터 분석을 실시한 후, 어셈블리(assembly)와 annotation을 수행하였다. RNA-seq raw 데이터로부터 약 84.2%, 81.5%에 해당하는 16.5Gb, 16.2Gb의 transcriptome 데이터를 확보하였다. 47Mb에 해당하는 43,494개의 대표적인 전사체(representative transcripts)를 확보하였고, 그 중에서 annotation DB와 서열 유사도를 갖는 서열은 23,165개로 확인되었다. 메밀의 representative transcripts 유전자의 유전자 온톨로지(gene ontology) 분석결과, biological process는 metabolic process (49.49%)에서, cellular components는 cell (46.12%)에서, molecular function은 catalyltic activity (80.43%)에서 유전자가 많이 분포되어 있는 것을 확인하였다. 종자의 발아에 관련된 gibberellin receptor GID1C의 경우에는 양절메밀, 대관 3-3호의 발현양이 모두 시간이 지남에 따라 증가되는 것을 확인할 수 있었으며, gibberellin 20-oxidase1의 경우에는 양절메밀에서는 발아 후 12 시간이내에 증가되었으나, 대관 3-3호에서는 36시간까지 유전자 발현양 증가하는 것을 확인할 수 있었다. 이러한 제주산 메밀의 발아초기 단계별 전사체 분석 데이터는 종간의 기능적, 형태학적 차이를 일으키는 메커니즘 규명에 도움을 줄 것으로 사료된다.