• Mycobiology
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• v.41 no.3
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• pp.121-125
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• 2013

Arbuscular mycorrhizal fungi (AMF) have mutualistic relationships with more than 80% of terrestrial plant species. This symbiotic relationship is ancient and would have had important roles in establishment of plants on land. Despite their abundance and wide range of relationship with plant species, AMF have shown low species diversity. However, molecular studies have suggested that diversity of these fungi may be much higher, and genetic variation of AMF is very high within a species and even within a single spore. Despite low diversity and lack of host specificity, various functions have been associated with plant growth responses to arbuscular mycorrhizal fungal colonization. In addition, different community composition of AMF affects plants differently, and plays a potential role in ecosystem variability and productivity. AMF have high functional diversity because different combinations of host plants and AMF have different effects on the various aspects of symbiosis. Consequently, recent studies have focused on the different functions of AMF according to their genetic resource and their roles in ecosystem functioning. This review summarizes taxonomic, genetic, and functional diversities of AMF and their roles in natural ecosystems.

• Journal of Forest and Environmental Science
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• v.32 no.3
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• pp.291-301
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• 2016

One of the most concerned topics in ecology is the relationship between biodiversity and ecosystem functioning. However, there are few field studies, carried out in forests, although many studies have been done in controlled experiments in grasslands. In this paper, we describe the relationship pattern between three facets of diversity and productivity at Ratargul Fresh Water Swamp Forest (RFWSF) in Bangladesh, which is the only remaining fresh water swamp forest of the country. Sixty sample plots were selected from RFWSF and included six functional traits including leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), tree height, bark thickness and wood density. In analyzing TD, we used Shannon diversity and richness indices, functional diversity was measured by Rao's quadratic entropy (Rao 1982) and Faith's (1992) index was used for phylogenetic diversity (PD). It was found that, TD, FD and PD were positively related with productivity (basal area) due to resource use complementarity but surprisingly the best predictor of tree productivity was FD. The results contribute to the understanding the effects of biodiversity loss and it is essential for conservation decision-making and policy-making of Ratargul Fresh Water Swamp Forest.

• Molecules and Cells
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• v.27 no.2
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• pp.225-235
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• 2009

Antibody phage display provides a powerful and efficient tool for the discovery and development of monoclonal antibodies for therapeutic and other applications. Antibody clones from synthetic libraries with optimized design features have several distinct advantages that include high stability, high levels of expression, and ease of downstream optimization and engineering. In this study, a fully synthetic human scFv library with six diversified CDRs was constructed by polymerase chain reaction assembly of overlapping oligonucleotides. In order to maximize the functional diversity of the library, a ${\beta}$-lactamase selection strategy was employed in which the assembled scFv gene repertoire was fused to the 5'-end of the ${\beta}$-lactamase gene, and in-frame scFv clones were enriched by carbenicillin selection. A final library with an estimated total diversity of $7.6{\times}10^9$, greater than 70% functional diversity, and diversification of all six CDRs was obtained after insertion of fully randomized CDR-H3 sequences into this proofread repertoire. The performance of the library was validated using a number of target antigens, against which multiple unique scFv sequences with dissociation constants in the nanomolar range were isolated.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.263-278
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• 2015

This study is intended to evaluate the value of functional aspect from the viewpoint of habitat. The indicators that are used in biotope evaluations are various, but most of them use the criteria to evaluate the naturality. This evaluation method cannot appropriately reflect the functional characteristics coming from relation to the surrounding biotope. In this study, the connectivity, cohesion and diversity between individual biotope are quantitatively measured by a landscape index. It is hard to draw the functional value of individual biotopes because the landscape index related to connectivity, cohesion and diversity comes from a landscape having a number of biotopes. The concept of contribution was used to overcome this limitation. The concept of contribution is to quantify how much each individual biotope contributes to the connectivity, cohesion, and diversity in a certain range of landscape by deriving the amount of change in the landscape index according to the presence or absence of each individual biotope. In order to understand the characteristics of evaluation results in functional aspect, this research has done a comparative analysis of the previous research findings in the same target area. According to the result of the research, individual biotopes such as artificial forests, fragmented natural forests, and small planting sites were highly rated.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.220-220
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• 2022

Disproportionating Enzyme 1 (DPE1) is an a-1,4-D-glucanotransferase that cleavages the a-1,4-glucosidic bonds and transfers glucosyl groups. In rice endosperm, it participates in starch synthesis by transferring maltooligosyl groups from amylose and amylopectin to amylopectin. Here, we investigated the haplotype variations and evolutionary indices (e.g., genetic diversity and population structure) for the DPE1 gene in 374 rice accessions representing seven subgroups (wild, indica, temperate japonica, tropical japonica, aus, aromatic, and admixture). Variant calling analysis of DPE1 coding regions leads to the identification of six functional haplotypes representing/occupying 8 nonsynonymous SNPs. Nucleotide diversity analysis revealed the highest pi-value in wild group (0.0556) compared to other cultivated groups, of which temperate japonica showed the most reduction of genetic diversity value (0.003). A significant positive Tajima's D value (1.6330) of admixture highlights sudden population contraction under balancing selection, while temperate japonica with the lowest Tajima's D value (-1.3523) showed a selection signature of DPE1 domestication which might be the cause of excess of rare alleles. Moreover, these two subpopulations exhibits a greater differentiation (F_ST=0.0148), indicating a higher genetic diversity. Our findings on functional DPE1 haplotypes will be useful in future breeding programs, and the evolutionary indices can also be applicable in functional studies of the DPE1 gene.

• PNF and Movement
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• v.2 no.1
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• pp.35-47
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• 2004

Purpose : The purpose of this article was to review the literature on contractile properties of skeletal muscle with reference to its molecular and functional diversity. Method : This review outlines scientific findings regarding different contractile properties in skeletal muscle fibers, and discusses their involvement in functional diversity. Result & Conclusions: Muscle fibers possess distinct mechanical and energetic properties. Myosis, one of the primary contractile muscle proteins, displays structural, functional variability and plays the role of the molecular motor of muscle contraction. Muscle satellite cells are normally mitotically quiescent, but initiate proliferation and give rise to daughter myogenic precursor cells as required for the postnatal growth and regeneration of adult muscle. Passive extensibility is an important component of total muscle function because it allows for the maximal length of skeletal muscles. Proprioceptive neuromuscular facilitation(PNF) stretching can help to restore or improve flexibility and coordination, thereby improving overall muscle function.

• Korean Journal of Ecology and Environment
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• v.53 no.1
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• pp.31-45
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• 2020

The biological indices based on the community structure with species richness and/or abundance are commonly used to assess aquatic ecosystem health. Meanwhile, recently functional traits-based approach is considered in ecosystem health assessment to reflect ecosystem functioning. In this study, we developed a database of biological traits for 136 taxa consisting of major stream insects (Ephemeroptera, Plecoptera, Trichoptera, Coleoptera, and Odonata) collected at Korean streams on the nationwide scale. In addition, we obtained environmental variables in five categories (geography, climate, land use, hydrology and physicochemistry) measured at each sampling site. We evaluated the relationships between community indices based on taxonomic diversity and functional diversity estimated from biological traits. We classified sampling sites based on similarities of their environmental variables and evaluated relations between clusters of sampling sites and diversity indices and biological traits. Our results showed that functional diversity was highly correlated with Shannon diversity index and species richness. The six clusters of sampling sites defined by a hierarchical cluster analysis reflected differences of their environmental variables. Samples in cluster 1 were mostly from high altitude areas, whereas samples in cluster 6 were from lowland areas. Non-metric multidimensional scaling (NMDS) displayed similar patterns with cluster analysis and presented variation of taxonomic diversity and functional diversity. Based on NMDS and community-weighted mean trait value matrix, species in clusters 1-3 displayed the resistance strategy in the life history strategy to the environmental variables whereas species in clusters 4-6 presented the resilience strategy. These results suggest that functional diversity can complement the biological monitoring assessment based on taxonomic diversity and can be used as biological monitoring assessment tool reflecting changes of ecosystem functioning responding to environmental changes.

• Korean Journal of Medicinal Crop Science
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• v.20 no.6
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• pp.440-446
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• 2012

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 diversity was lower than other plant and most genetic diversity was allocated among individuals within populations (26.81%). The UPGMA dendrogram based on genetic distance failed in showing decisive geographic relationship. In the case of gastrodin (GA), the major components in G. elata, Sangju was highest. The ergothionine (ERG) was detected a lot of contents in Muju and Pocheon. In conclusion, our results is very important information for explaining relationship of genetic variation and functional substances without the effects of environment factors and developing genetic marker by ISSR in G. elata, which may be responsible for the development of breeds with a lot of functional substance in G. elata.

• ALGAE
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• v.34 no.2
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• pp.99-109
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• 2019

Habitat-forming species increase spatial complexity and alter local environmental conditions, often facilitating the assembly of plants and animals. We conducted a trait-based approach to algal assemblages associated with the freshwater bryozoan, Pectinatella magnifica. Association with algae leads to the inner bodies of the bryozoans being colored green; this is frequently observed in the large rivers of South Korea. We collected the green-colored gelatinous matrices and phytoplankton from waterbodies of the two main rivers in South Korea. Algal assemblages within the colonies and in the waterbodies were compared using the three diversity indices (richness, diversity, and dominance), and the composition of functional groups (FGs) and morphologically based functional groups (MBFGs) between the colonies within and outside of P. magnifica colonies. The most dominant and common species within the colonies were Oscillatoria kawamurae and Pseudanabaena catenata, both of which were assigned to the same FG (codon S1). Of the algal assemblages within the colonies, the dominance was higher, while the richness and diversity were lower, than those in the waterbodies. There was variation in the compositions of FGs and MBFGs in the waterbodies outside the colonies. Total nitrogen and orthophosphate led to dominance, and were significant factors for the variation in FGs in the waterbodies, whereas there were no such significant factors within the colonies. This trait-based approach to the community structure of associated algae provides the status and habitat gradient of these communities, which are stable, isolated, and consistent with the overgrowth of shade-adapted tychoplanktonic cyanobacteria.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.2
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• pp.144-156
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• 2016

Soil is a dynamic biological system, in which it is difficult to determine the composition of microbial communities. Knowledge of microbial diversity and function in soils are limited because of the taxonomic and methodological limitations associated with studying the organisms. In this review, approaches to measure microbial diversity in soil were discussed. Research on soil microbes can be categorized as structural diversity, functional diversity and genetic diversity studies, and these include cultivation based and cultivation independent methods. Cultivation independent technique to evaluate soil structural diversity include different techniques such as Phospholipid Fatty Acids (PLFA) and Fatty Acid Methyl Ester (FAME) analysis. Carbon source utilization pattern of soil microorganisms by Community Level Physiological Profiling (CLPP), catabolic responses by Substrate Induced Respiration technique (SIR) and soil microbial enzyme activities are discussed. Genetic diversity of soil microorganisms using molecular techniques such as 16S rDNA analysis Denaturing Gradient Gel Electrophoresis (DGGE) / Temperature Gradient Gel Electrophoresis (TGGE), Terminal Restriction Fragment Length Polymorphism (T-RFLP), Single Strand Conformation Polymorphism (SSCP), Restriction Fragment Length Polymorphism (RFLP) / Amplified Ribosomal DNA Restriction Analysis (ARDRA) and Ribosomal Intergenic Spacer Analysis (RISA) are also discussed. The chapter ends with a final conclusion on the advantages and disadvantages of different techniques and advances in molecular techniques to study the soil microbial diversity.