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Jung, Y.

Publications and source records attributed to Jung, Y..

4 recordsLinked to original sources

High-throughput retrieval of physical DNA for NGS-identifiable clones in phage display library

In antibody discovery, in-depth analysis of an antibody library and high-throughput retrieval of clones in the library are crucial to identifying and exploiting rare clones with different properties. However, existing methods have several technical limitations such as low process throughput from laborious cloning process and waste of the phenotypic screening capacity from unnecessary repetitive tests on the dominant clones. To overcome the limitations, we developed a new high-throughput platform for the identification and retrieval of clones in the library, TrueRepertoire. TrueRepertoire provides highly accurate sequences of the clones with linkage information between heavy and light chains of the antibody fragment. Additionally, the physical DNA of clones can be retrieved in high throughput based on the sequence information. We validated the high accuracy of the sequences and demonstrated that there is no platform-specific bias. Moreover, the applicability of TrueRepertoire was demonstrated by a phage-displayed single-chain variable fragment (scFv) library targeting human hepatocyte growth factor (hHGF) protein.

bioengineering

C. elegans Mediator 15 permits low temperature-induced longevity via regulation of lipid and protein homeostasis

Low temperatures slow aging and extend lifespan in many organisms, including Caenorhabditis elegans. However, the metabolic and homeostatic aspects of low temperature-induced longevity remain poorly understood. Here, we show that changes in lipid composition regulated by MDT-15/Mediator 15, transcriptional co-regulator, is essential for low temperature-induced longevity and proteostasis in C. elegans. We find that inhibition of mdt-15 prevents animals from living long at low temperatures. We show that MDT-15 up-regulates fat-7, a fatty acid desaturase, at low temperatures, which increases the ratio of unsaturated to saturated fatty acids. We further demonstrate that maintaining this increased fatty acid ratio is essential for protein homeostasis and longevity at low temperatures. Thus, the homeostasis of lipid composition by MDT-15 appears to be a limiting factor for C. elegans proteostasis and longevity at low temperatures. Our findings highlight the crucial roles of fat regulation in maintaining normal organismal physiology under different environmental conditions.

developmental biology

Constructing and visualizing cancer genomic maps in 3D spatial context by phenotype-based high-throughput laser-aided isolation and sequencing (PHLI-seq)

A spatially resolved analysis of the heterogeneous cancer genome, in which the data are connected to the three-dimensional space of a tumour, is crucial to understand cancer biology and the clinical impact of cancer heterogeneity on patients. However, despite recent progress in spatially resolved transcriptomics, spatial mapping of genomic data in a high-throughput and high-resolution manner has been challenging due to current technical limitations. Here, we describe a novel approach, phenotype-based high-throughput laser-aided isolation and sequencing (PHLI-seq), which enables high-throughput isolation of a single-cell or a small number of cells and their genome-wide sequence analysis to construct genomic maps within cancer tissue in relation to the phenotypes of the cells. By applying PHLI-seq, we reveal the heterogeneity of breast cancer tissues at a high resolution and map the genomic landscape of the cells to their corresponding spatial locations and phenotypes in the tumour mass. Additionally, with different staining modalities, the genotypes of the cells can be connected to corresponding phenotypic information of the tissue. Together with the spatially resolved genomic analysis, we can infer the histories of heterogeneous cancer cells in two or three dimensions, providing significant insight into cancer biology and precision medicine.

genomics

Modality-Independent Coding Of Concepts In Prefrontal Cortex

Natural environments convey information through multiple sensory modalities, all of which contribute to peoples percepts. Although it has been shown that visual or auditory content of scene categories can be decoded from brain activity, it remains unclear where and how humans integrate different sensory inputs and represent scene information beyond a specific sensory modality domain. To address this question, we investigated how categories of scene images and sounds are represented in several brain regions. A mixed gender group of healthy human subjects participated the present study, where their brain activity was measured with fMRI while viewing images or listening to sounds of different places. We found that both visual and auditory scene categories can be decoded not only from modality-specific areas, but also from several brain regions in the temporal, parietal, and prefrontal cortex. Intriguingly, only in the prefrontal cortex, but not in any other regions, categories of scene images and sounds appear to be represented in similar activation patterns, suggesting that scene representations in the prefrontal cortex are modality-independent. Furthermore, the error patterns of neural decoders indicate that category-specific neural activity patterns in the middle and superior frontal gyri are tightly linked to categorization behavior. Our findings demonstrate that complex scene information is represented at an abstract level in the prefrontal cortex, regardless of the sensory modality of the stimulus.\n\nStatement of SignificanceOur experience in daily life requires the integration of multiple sensory inputs such as images, sounds, or scents from the environment. Here, for the first time, we investigated where and how in the brain information about the natural environment from multiple senses is merged to form modality-independent representations of scene categories. We show direct decoding of scene categories across sensory modalities from patterns of neural activity in the prefrontal cortex. We also conclusively tie these neural representations to human categorization behavior based on the errors from the neural decoder and behavior. Our findings suggest that the prefrontal cortex is a central hub for integrating sensory information and computing modality-independent representations of scene categories.

neuroscience