Eung-Jun Park

National Institute of Forest Science, South Korea · Tree Biotechnology

Wood is the most important renewable resource not only for numerous practical utilizations but also for mitigating the global climate crisis by sequestering atmospheric carbon dioxide. The compressed wood (CW) of gymnosperms, such as conifers, plays a pivotal role in determining the structure of the tree through the reorientation of stems displaced...

The genome of Populus davidiana, a keystone aspen species, has been sequenced to improve our understanding of the evolutionary and functional genomics of the Populus genus. The Hi-C scaffolding genome assembly resulted in a 408.1 Mb genome with 19 pseudochromosomes. The BUSCO assessment revealed that 98.3% of the genome matched the embryophytes dat...

We report the high-quality genome sequence of Tricholoma matsutake strain 2001, which was isolated from a mushroom fruiting body in South Korea. The genome has 80 contigs, a size of 162.6 Mb, and an N50 value of 5,103,859 bp and will provide insight into the symbiotic association between T. matsutake and Pinus densiflora.

Tracheary elements (i.e., vessel elements and tracheids) are highly specialized, non-living cells present in the water-conducting xylem tissue. In angiosperms, proteins in the VASCULAR-RELATED NAC-DOMAIN (VND) subgroup of the NAC transcription factor family (e.g., AtVND6) are required for the differentiation of vessel elements through transcription...

Gastrodia elata, an obligate mycoheterotrophic orchid, requires complete carbon and mineral nutrient supplementation from mycorrhizal fungi during its entire life cycle. Although full mycoheterotrophy occurs most often in the Orchidaceae family, no chromosome-level reference genome from this group has been assembled to date. Here, we report a high-...

Both anthocyanins and lignins are essential secondary metabolites in plant growth and development. Their biosynthesis is metabolically interconnected and diverges in the central metabolite 4-coumaroyl CoA of the phenylpropanoid pathway. Considerable progress has been made in understanding transcriptional regulation of genes involved in lignin and a...

Although conifers have significant ecological and economic value, information on transcriptional regulation of wood formation in conifers is still limited. Here, to gain insight into secondary cell wall (SCW) biosynthesis and tracheid formation in conifers, we performed wood tissue-specific transcriptome analyses of Pinus densiflora (Korean red pin...

Drought stress is one of the major environmental problems in the growth of crops and woody perennials, but it is getting worse due to the global climate crisis. XERICO, a RING (Really Interesting New Gene) zinc-finger E3 ubiquitin ligase, has been shown to be a positive regulator of drought tolerance in plants through the control of abscisic acid (...

Kalopanax septemlobus is a deciduous medicinal tree species belonging to the family Araliaceae. It contains a number of triterpenoid saponins primarily constituted of hederagenin aglycones. Here, we presented de novo comparative transcriptome analysis using 454 pyrosequencing technology between embryogenic (EC) and nonembryogenic callus (NEC) of K....

The TALE (Three Amino acid Loop Extension) transcription factor family has been shown to control meristem formation and organogenesis in plants. To understand the functional roles of the TALE family in woody perennials, each of the TALE members of Populus trichocarpa was overexpressed in Arabidopsis as a proxy. Among them, the overexpression of Ptr...

Increasing our understanding of how evolutionary processes drive the genomic landscape of variation is fundamental to a better understanding of the genomic consequences of speciation. However, genome‐wide patterns of within‐ and between‐ species variation have not been fully investigated in most forest tree species despite their global ecological a...

The completed chloroplast genome of Gastrodia elata Blume (G. elata) from Korea was determined in this study. The cpDNA is 35,230 bp in length and lacked the large and small single copy (LSC and SSC) regions, due to the lost inverted repeat (IR). The overall AT content is 73.30%, and the cpDNA contains 20 protein-coding genes, 5 tRNA genes, and 3 r...

Increasing our understanding of how various evolutionary processes drive the genomic landscape of variation is fundamental to a better understanding of the genomic consequences of speciation. However, the genome-wide patterns of within- and between- species variation have not been fully investigated in most forest tree species despite their global...

Nut weight is one of the most important traits that can affect a chestnut grower's returns. Due to the long juvenile phase of chestnut trees, the selection of desired characteristics at early developmental stages represents a major challenge for chestnut breeding. In this study, we identified single nucleotide polymorphisms (SNPs) in transcriptomic...

Wood, the most abundant biomass on Earth, is composed of secondary xylem differentiated from vascular cambium. However, the underlying molecular mechanisms of wood formation remain largely unclear. To gain insight into wood formation, we performed a series of wood-forming tissue-specific transcriptome analyses from a hybrid poplar (Populus alba × P...

The complete chloroplast genome sequence of Castanea crenata was sequenced and assembled using PacBio Sequel data. The cpDNA was 160,787 bp in length, containing a pair of inverted repeats (IRs) of 25,654 bp each separated by a large and small single copy (LSC and SSC) regions of 90,645 bp and 18,836 bp, respectively. The cpDNA contained 102 genes,...

Figure S1 Schematic diagram of vector construction for bicistronic gene expression under the control of the DX15 promoter used in producing transgenic plants. Figure S2 PtrMYB221, a poplar MYB transcription factor, is the closest homolog of EgMYB1. Figure S3 Stem‐specific expression of PdGA20ox1 transcripts in transgenic poplar plants. Figure S4...

With the exponential growth of the human population and industrial developments, research on renewable energy resources is required to alleviate environmental and economic impacts caused by the consumption of fossil fuels. In this study, we present a synthetic biological application of a wood forming tissue‐specific bicistronic gene expression syst...

Significance We performed de novo, full-genome sequence analysis of two Populus species, North American quaking and Eurasian trembling aspen, that contain striking levels of genetic variation. Our results showed that positive and negative selection broadly affects patterns of genomic variation, but to varying degrees across coding and noncoding reg...

Key message Downregulating PagSAP1 expression increases salt tolerance in poplar and leads to the alterations in the regulation of genes involved in maintaining cellular ionic homeostasis. Abstract Plants have evolved defense mechanisms to cope with unfavorable climate conditions such as salinity, drought, and extreme temperatures. Such adaptive s...

Background and aims: Anisotropic cell elongation depends on cell wall relaxation and cellulose microfibril arrangement. The aim of this study was to characterize the molecular function of AtDICE1 encoding a novel transmembrane protein involved in anisotropic cell elongation in Arabidopsis. Methods: Phenotypic characterizations of transgenic Arab...

ABSTRACT Background: Gastrodia elata Blume is a saprophytic perennial plant in the Orchidaceae family and its agricultural and medicinal effectiveness spurs researches on its genome and chemical components. But, there is very limited cytogenetic information based on chromosome structure and composition to construct chromosomal backbone for genome...

A phenotype-based screening of the T1 transgenic Arabidopsis population transformed by overexpression constructs of the entire poplar MYB transcription factor family found that overexpression of a poplar MYB transcription factor, PtrMYB012, in Arabidopsis resulted in upwardly curled rosette leaves, dwarfism and male sterility. Sequence analysis ide...

The genus Populus contains 25–35 species of deciduous flowering plants in the family Salicaceae. It has evolved to overcome various environmental stresses including drought stress through changes in physiological processes such a stomatal movement, photosynthesis, stress signaling, defense responses, and overall growth rate. In this study, we perfo...

Benzoic acids (BAs) are important structural elements in a wide variety of essential compounds and natural products, and play crucial roles in plant fitness. BA is a precursor of diverse benzenoid compounds, including the hormone salicylic acid (SA) and the aglycone moiety of salicin, which is particularly important in the Salicaceae family. The bi...

Populus davidiana is native to the Korean Peninsula and is one of the most dominant and abundantly growing forest trees in eastern Asia. Compared to other Populus species such as P. trichocarpa, P. euphratica, and P. tremula, relatively little is known about P. davidiana. Here, we performed transcriptomic analysis of P. davidiana under drought stre...

Gastrodia elata belongs to the Orchidaceae family and is one of the most popular medicinal herbs used for patients with convulsion, ischemia, dementia, tremors, and vertigo. G. elata must develop symbiotic relationships with two compatible fungi, Mycena osmundicola and Armillaria mellea, for seed germination and vegetative growth, respectively (†)....

This study investigated the in vitro symbiotic seed germination of the achlorophyllous orchid, Gastrodia elata, using a new Mycena species. A leaf-disc (2x2 cm) of Quercus accutissima was inoculated with either of the two fungal species, NIFOS101 (NCBI accession number KY449288) or KFRI1212 (HQ662845), following which it was placed on water agar me...

This study sequenced the entire mitochondrial genome of Populus davidiana Dode. It was 779,361 bp in length, containing 33 protein-coding genes, 3 rRNA genes and 22 tRNA genes and 1 pseudogene, and its GC content was 44.8%. Phylogenetic analysis was conducted using 6 mitochondrial genomes from the Salicaceae and Euphorbiaceae families, resulting th...

Due to wood's potential for large-scale commercial production of biofuels, a rapid increase in the use of wood as a source of energy is expected as policies promoting greater use of renewable energy are adopted globally. However, the economics of purpose-grown tree feedstocks for energy show that these production systems are not financially viable...

Gastrodia elata is an achlorophyllous orchid that must be colonized by the wood-rotting pathogen Armillaria mellea for its growth and development (Kusano 1911). G. elata is grown and harvested as a medicinal herb in the mountainous areas of Korea, China, Japan, and India (Jones 1991). The soft rot disease of G. elata has recently caused 60% losses...

Unlike xylem, which is primarily composed of dead cells in vascular bundles, phloem has living cells. It transports organic nutrients and long-distance communication signals to all parts of plants. In this report, we describe a promoter from Populus trichocarpa that drives strong gene expression in a phloem tissue-specific manner. First, we identif...

The complete chloroplast genome sequence of Populus davidiana Dode was determined in this study. The cpDNA was 155,853 bp in length, containing a pair of inverted repeats (IRs) of 27,571 bp each separated by a large and small single copy (LSC and SSC) regions of 84,127 bp and 16,584 bp, respectively. The cpDNA contained 130 genes, including 85 prot...

Anthocyanins are a group of colorful and bioactive natural pigments with important physiological and ecological functions in plants. We found an MYB transcription factor (PtrMYB119) from Populus trichocarpa that positively regulates anthocyanin production when expressed under the control of the CaMV 35S promoter in transgenic Arabidopsis. Amino aci...

Woody biomass has gained popularity as an environmentally friendly, renewable and sustainable resource for liquid fuel production. Here, we demonstrate biotechnological improvement of the quantity and quality of woody biomass by employing developing xylem (DX)-preferential production of gibberellin (GA), a phytohormone that positively regulates ste...

Gibberellins (GAs) are important regulators of plant shoot biomass growth, and GA 20-oxidase (GA20ox) is one of the major regulatory enzymes in the GA biosynthetic pathway. Previously, we showed that the expression levels of a putative GA20ox1 (i.e., PdGA20ox1) in stem tissue of 3-month-old seedlings of 12 families of Pinus densiflora were positive...

Acorn production varies considerably among individual trees, years, and locations, which directly affect oak regeneration and populations of wildlife species. This study was conducted to estimate the acorn production capacities of trees in a clonal seed orchard (CSO) of Quercus acutissima by analyzing the relationship among morphological characteri...

A retrospective metabolomics approach was utilized as a tool in genomics-assisted selection for forest tree improvement. Key metabolic components were thus correlated with the inherently rapid stem growth of Pinus densiflora Siebold & Zucc. trees, including water soluble metabolites and amino acids found in the inner bark (phloem) of cambial region...

Monodehydroascorbate reductase (MDHAR) is an important enzyme that plays a role in the detoxification of reactive oxygen species (ROS) by maintaining reduced pool of ascorbate through recycling the oxidized form of ascorbate. In this study, we isolated a PagMDHAR1 gene from Populus alba × P. glandulosa, and investigated its expression characteristi...

Gastrodia elata Blume, an achlorophyllous orchid plant, has been used in traditional medicine and harvests in spring and fall. Here we investigated the quantitative changes of amino acids in G. elata by harvest times and seed tubers. In the results, we found that there was not big difference in contents of total amino acids but the distribution of...

In an even-aged pine forest trees can vary considerably in stem size. We examined the basis for this anomaly using a retrospective approach. Twelve open-pollinated families of Pinus densiflora Sieb. et Zucc. were deliberately chosen for their variation in stem volumes at age 32 years. Seedlings obtained from these families were grown to age 6 month...

Drought and salt stresses are major environmental constraints on forest productivity. To identify genes responsible for stress tolerance, we conducted a genome-wide analysis in poplar (Populus alba × Populus glandulosa) leaves exposed to drought and salt (NaCl) stresses. We investigated gene expression at the mRNA level using oligonucleotide microa...

Nutritional composition, including total phenolics, tannins and nutrient components, of acorns of Q. actissima, Q. serrata, Q. variabilis and Q. mongolica were analyzed. Acorns were collected from each tree species, which were grown in a seed orchard. Contents of both total phenolics and tannins in acorns of Q. serrata were higher than those of Q....

A metabolomic study using GC/MS analysis was conducted to identify key metabolic components regulating the growth of open-pollinated Pinus koraiensis families, which were grown for 29 years at three different locations. Among 110 individual metabolites identified, the contents of 62 metabolites were higher in the superior than in the inferior famil...

In order to identify major metabolic components involved in the regulation of superior clonal seedling’s growth ofPopulus davidiana, we compared various clonal growth parameters (total dry weight, stem dry weight, and leaf dry weight) withthe levels of metabolites in either leaf or stem of the corresponding rooted cutting seedlings. In leaf tissues...

Gastrodia elata Blume is a achlorophyllous orchid plant that has been used in traditional medicine to treat many human illnesses, such as vertigo, hemiplegia, and epilepsy. It contains three major pharmacological substances; gastrodin, ergothioneine, and vanillyl alcohol. Here we investigated the quantitative changes in those functional components...

Gastrodia elata is a myco-heterotrophic orchid that has been used in traditional medicine to treat number of human illnesses. It establishes symbiotic associations with compatible mycorrhizal fungi, such as Mycena species and Armillaria mellea, depending on its developmental stages. G. elata tubers contain two major pharmacological substances; gast...

Gastrodia elata has been cultivated as an important medicinal resources to treat various human diseases. One of the major problems associated with its field production is the degeneration of seed tubers, which is mainly caused by soil-borne pathogens. This study was conducted to produce disease-free seed tubers by the development of in vitro microp...

Symbiotic germination was analyzed in the myco-heterotrophic orchid Gastrodia elata. Seeds were placed on water agar medium containing a leaf-disc of Quercus accutissima that had been previously inoculated with one of six different Mycena species. Among the six fungi, KFRI1212 (HQ662845) and KFRI2121 (HQ662846) germinated 60.1 and 47.0 % seeds, res...

Japanese larch (Larix leptolepis) has been extensively planted in Korea as a reforestation species but their supply has been a major bottleneck due to sporadic natural seed production. In this study, stem girdling was applied to 32-year-old grafted Japanese larches, resulting in significantly enhanced seed production compared to the controls. Stem...

Gastrodia elata, an achlorophyllous orchid plant, is rare medicinal plant. We investigated the genetic diversity in G. elata from 4 locations by using Inter-Simple Sequence Repeats (ISSR) markers. Shannon's information Index (S.I.) indicating genetic diversity ranged from 0.255 (Pocheon) to 0.322 (Muju) with the mean of 0.29. The level of genetic d...

We have established adventitious root culture systems of Codonopsis lanceolata, Codonopsis pilosula and Codonopsis ussuriensis. Root segments of C. lanceolata were the best explants for induction of adventitious roots and the number of adventitious root for explant was highest on solid medium with NAA and produced roots per explant. Root segments o...

Gastrodia elata must establish symbiotic associations with different compatible fungi at seed germination and during vegetative growth. One of the major problems associated with its field production is the degeneration of tubers, which is mainly caused by multiple regeneration via vegetative propagation using immature tubers. To overcome this probl...

The demand for Japanese larch (Larix leptolepis) seeds has increased in Korea but their supply has been limited due to sporadic natural seed production. Among the various flower induction techniques, girdling woody stems has been recognized as a simple and efficient method to enhance seed production in a number of conifers. In this study, stem gird...

This study was carried out to investigate the dose-dependent effect of salicylic acid on both the adventitious root growth and the accumulation of various eleutherosides in the bioreactor culture of Eleutherococcus senticosus. The highest biomass production (5.4 g DW/L) was observed in the absence of salicylic acid, while the root growth was signif...

Ergothioneine (ERG) has long been recognized as a potent and stable antioxidant. In nature, ERG is synthesized only in fungi and mycobacteria, not in plants. The lifecycle of Gastrodia elata, an achlorophyllous orchid plant, is completely dependent on the presence of symbiotic fungi, particularly Armillaria mellea. In this study, we report for the...

The aim of this study was to investigate the effect of tryptophan (Trp) on the production of total phenolic compounds (TP) in the mycelial culture of Ganoderma neo-japonicum (G. neo-japonicum). Among various amino acids tested, Trp was best for increasing the TP content by 13.2-fold compared to the control. Trp also increased the phenylalanine cont...

In this study, we investigated the relationship of tree-ring growth with total nitrogen content, and stable carbon and nitrogen isotopes from the core samples of Pinus koraiensis (35-year-old). Annual ring width showed significant positive correlations with the (P=0.003). The total nitrogen content (P=0.024), and the content was also correlated wit...

The levels of ergothioneine (ERG), which have been shown to act as an excellent antioxidant, were determined in both fruiting bodies and mycelia of various mushroom species. We found that ERG accumulated at different levels in fruiting bodies of mushrooms and showed up to a 92.3-fold difference between mushrooms. We also found that ERG accumulated...

The methods for increasing the production of ergothioneine (ERG) were investigated by using the mycelial culture of several mushroom species, primarily Ganoderma neo-japonicum. We first found that ERG was accumulated at the different levels in mycelia and fruiting bodies, respectively, depending on the mushroom species. As a result of adding variou...

This study was carried out to investigate the promoting effect of wood flour on the mycelial growth of Lentinus lepideus and Lentinus edodes. To determine the optimal culture condition, we first examined the tissue origin of pine flour (Pinus densiflora) including needle, bark, root and xylem. Only the xylem-derived flour increased mycelial growth...

Solanum tuberosum is a frost-sensitive species incapable of cold acclimation. A brief exposure to frost can significantly reduce its yields, while hard frosts can completely destroy entire crops. Thus, gains in freezing tolerance of even a few degrees would be of considerable benefit relative to frost damage. The S. tuberosum cv. Umatilla was trans...

Tomato (Lycopersicon esculentum Mill. cv. Moneymaker) plants were transformed with a gene for choline oxidase (codA) from Arthrobacter globiformis. The gene product (CODA) was targeted to the chloroplasts (Chl-codA), cytosol (Cyt-codA) or both compartments simultaneously (ChlCyt-codA). These three transgenic plant types accumulated different amount...

The tolerance of various species of plant to abiotic stress has been enhanced by genetic engineering with certain genes. However, the use of such transgenes is often associated with negative effects on growth and productivity under non-stress conditions. The codA gene from Arthrobacter globiformis is of particular interest with respect to the engin...

Chilling and freezing temperatures often adversely affect the productivity and quality of horticultural plants. Attempts to enhance cold tolerance through traditional breeding have achieved limited success, mainly due to the complexity of the genetics associated with a plant's response to low temperatures. Recently, the improvement of cold toleranc...

Potato is a valuable source of antioxidants in the human diet and their genetic variability exists for antioxidant activity. This study was carried out to define selection criteria for potato varieties and breeding clones with high antioxidant levels as measured by 1,1-diphenyl-2-picryl-hydrazyl methods. There were significant differences in antiox...