Category Archives: 研究發表

Next generation sequencing reveals miR-431–3p/miR-1303 as immune-regulating microRNAs for active tuberculosis

陳亭妏助理教授研究團隊發表研究成果於 Journal of Infection

連結網址:https://www.sciencedirect.com/science/article/pii/S0163445322005175?via%3Dihub

Summary

Objectives: RNA therapeutics is an emerging field that widens the range of treatable targets and would improve disease outcome through bypassing the antibiotic bactericidal targets to kill Mycobacterium tuberculosis (M.tb).
Methods: We screened for microRNA with immune-regulatory functions against M.tb by next generation sequencing of peripheral blood mononuclear cells, followed by validation in an independent cohort.
Results: Twenty three differentially expressed microRNAs were identified between 12 active pulmonary TB patients and 4 healthy subjects, and 35 microRNAs before and after 6-month anti-TB therapy. Enriched predicted target pathways included proteoglycan, HIF-1 signaling, longevity-regulating, central carbon metabolism, and autophagy. We validated miR-431–3p down-regulation and miR-1303 up-regulation
accompanied with corresponding changes in their predicted target genes in an independent validation cohort of 46 active TB patients, 30 latent TB infection subjects, and 24 non-infected healthy subjects. In vitro experiments of transfections with miR-431–3p mimic/miR-1303 short interfering RNA in THP-1 cells under ESAT-6 stimuli showed that miR-431–3p and miR-1303 were capable to augment and suppress autophagy/apoptosis/phagocytosis of macrophage via targeting MDR1/MMP16/RIPOR2 and ATG5, respectively.
Conclusions: This study provides a proof of concept for microRNA-based host-directed immunotherapy for active TB disease. The combined miR-431–3p over-expression and miR-1303 knock-down revealed new vulnerabilities of treatment-refractory TB disease.

Long-term musical training induces white matter plasticity in emotion and language networks

謝仁俊教授研究團隊發表研究成果於Hum Brain Mapp

連結網址:https://pubmed.ncbi.nlm.nih.gov/36005832/

Abstract

Abstract: Numerous studies have reported that long-term musical training can affect brain functionality and induce structural alterations in the brain. Singing is a form of vocal musical expression with an unparalleled capacity for communicating emotion; however, there has been relatively little research on neuroplasticity at the network level in vocalists (i.e., noninstrumental musicians). Our objective in this study was to elucidate changes in the neural network architecture following long-term training in the musical arts. We employed a framework based on graph theory to depict the connectivity and efficiency of structural networks in the brain, based on diffusion-weighted images obtained from 35 vocalists, 27 pianists, and 33 nonmusicians. Our results revealed that musical training (both voice and piano) could enhance connectivity among emotion-related regions of the brain, such as the amygdala. We also discovered that voice training reshaped the architecture of experience-dependent networks, such as those involved in vocal motor control, sensory feedback, and language processing. It appears that vocal-related changes in areas such as the insula, paracentral lobule, supramarginal gyrus, and putamen are associated with functional segregation, multisensory integration, and enhanced network interconnectivity. These results suggest that long-term musical training can strengthen or prune white matter connectivity networks in an experience-dependent manner.

Structural determination of an antibody that specifically recognizes polyethylene glycol with a terminal methoxy group

蘇昱誠助理教授研究團隊發表研究成果於Communications Chemistry

連結網址:https://www.nature.com/articles/s42004-022-00709-0

Abstract

Covalent attachment of methoxy poly(ethylene) glycol (mPEG) to therapeutic molecules is widely employed to improve their systemic circulation time and therapeutic efficacy. mPEG, however, can induce anti-PEG antibodies that negatively impact drug therapeutic effects. However, the underlying mechanism for specific binding of antibodies to mPEG remains unclear. Here, we determined the first co-crystal structure of the humanized 15-2b anti-mPEG antibody in complex with mPEG, which possesses a deep pocket in the antigen-binding site to accommodate the mPEG polymer. Structural and mutational analyses revealed that mPEG binds to h15-2b via Van der Waals and hydrogen bond interactions, whereas the methoxy group of mPEG is stabilized in a hydrophobic environment between the VH:VL interface. Replacement of the heavy chain hydrophobic V37 residue with a neutral polar serine or threonine residue offers additional hydrogen bond interactions with methoxyl and hydroxyl groups, resulting in cross-reactivity to mPEG and OH-PEG. Our findings provide insights into understanding mPEG-binding specificity and antigenicity of anti-mPEG antibodies.

Stomatin modulates adipogenesis through the ERK pathway and regulates fatty acid uptake and lipid droplet growth

林奇宏教授研究團隊發表研究成果於 Nature communications

連結:https://www.nature.com/articles/s41467-022-31825-z

Abstract Regulation of fatty acid uptake, lipid production and storage, and metabolism of lipid droplets (LDs), is closely related to lipid homeostasis, adipocyte hypertrophy and obesity. We report here that stomatin, a major constituent of lipid raft, participates in adipogenesis and adipocyte maturation by modulating related signaling pathways. In adipocyte-like cells, increased stomatin promotes LD growth or enlargements by facilitating LD-LD fusion. It also promotes fatty acid uptake from extracellular environment by recruiting effector molecules, such as FAT/CD36 translocase, to lipid rafts to promote internalization of fatty acids. Stomatin transgenic mice fed with high-fat diet exhibit obesity, insulin resistance and hepatic impairments; however, such phenotypes are not seen in transgenic animals fed with regular diet. Inhibitions of stomatin by gene knockdown or OB-1 inhibit adipogenic differentiation and LD growth through downregulation of PPARγ pathway. Effects of stomatin on PPARγ involves ERK signaling; however, an alternate pathway may also exist.

APE1 distinguishes DNA substrates in exonucleolytic cleavage by induced space-filling

蕭育源教授研究團隊發表研究成果於 Nature communications

連結: https://www.nature.com/articles/s41467-020-20853-2

Abstract

The exonuclease activity of Apurinic/apyrimidinic endonuclease 1 (APE1) is responsible for processing matched/mismatched terminus in various DNA repair pathways and for removing nucleoside analogs associated with drug resistance. To fill in the gap of structural basis for exonucleolytic cleavage, we determine the APE1-dsDNA complex structures displaying end-binding. As an exonuclease, APE1 does not show base preference but can distinguish dsDNAs with different structural features. Integration with assaying enzyme activity and binding affinity for a variety of substrates reveals for the first time that both endonucleolytic and exonucleolytic cleavage can be understood by an induced space-filling model. Binding dsDNA induces RM (Arg176 and Met269) bridge that defines a long and narrow product pocket for exquisite machinery of substrate selection. Our study paves the way to comprehend end-processing of dsDNA in the cell and the drug resistance relating to APE1.

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