• Development and Reproduction
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• v.13 no.1
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• pp.13-23
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• 2009

Recent advances in cell biological and genetic researches have revealed that mitochondrial morphology is highly dynamic and regulated by multiple molecular factors including dynamin-related proteins (DRPs). Considering that the mitochondria play critical roles in the cellular metabolism via ATP synthesis, calcium homeostasis in cooperation with endoplasmic reticulum, and apoptosis, the failure of mitochondrial dynamics is infrequently related to the failure in the normal growth and cellular integrity. In this respect, alteration of mitochondrial dynamics may greatly affect the development of nervous system. In this short review, we discussed molecules involved in the control of mitochondrial dynamics, and provide some perspectives on their significance in the neuronal development.

• Journal of Marine Life Science
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• v.5 no.2
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• pp.92-98
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• 2020

Heat shock proteins (HSPs) are highly conserved cellular proteins that contribute to adaptive responses of organisms to a variety of stressors. In response to stressors, cellular levels of HSPs are increased and play critical roles in protein stability, folding and molecular trafficking. The mRNA expression pattern of two well-known heat shock protein transcripts, HSP70 and HSP90 were studied in two tissues of nerve ganglia, cerebral ganglion and pleuropedal ganglion of Pacific abalone (Haliotis discus hannai). It was observed that both HSP70 and HSP90 transcripts were upregulated under heat stress in both ganglion tissues. Expression level of HSP70 was found higher than HSP90 in both ganglia whereas cerebral ganglion showed higher expression than pleuropedal ganglion. The HSP70 and HSP90 showed higher expression at Day-1 after exposed to heat stress, later decreased at Day-3 and Day-7 onwards. The present result suggested that HSP70 and HSP90 synthesize in nerve ganglion tissues and may provide efficient protection from stress.

• Translational and Clinical Pharmacology
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• v.26 no.3
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• pp.103-110
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• 2018

The human microbiome is known to play an essential role in influencing host health. Extracellular vesicles (EVs) have also been reported to act on a variety of signaling pathways, distally transport cellular components such as proteins, lipids, and nucleic acid, and have immunomodulatory effects. Here we shall review the current understanding of the intersectionality of the human microbiome and EVs in the emerging field of microbiota-derived EVs and their pharmacological potential. Microbes secrete several classes of EVs: outer membrane vesicles (OMVs), membrane vesicles (MVs), and apoptotic bodies. EV biogenesis is unique to each cell and regulated by sophisticated signaling pathways. EVs are primarily composed of lipids, proteins, nucleic acids, and recent evidence suggests they may also carry metabolites. These components interact with host cells and control various cellular processes by transferring their constituents. The pharmacological potential of microbiome-derived EVs as vaccine candidates, biomarkers, and a smart drug delivery system is a promising area of future research. Therefore, it is necessary to elucidate in detail the mechanisms of microbiome-derived EV action in host health in a multi-disciplinary manner.

• BMB Reports
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• v.54 no.3
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• pp.157-163
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• 2021

The transient interactions between cellular components, particularly on membrane surfaces, are critical in the proper function of many biochemical reactions. For example, many signaling pathways involve dimerization, oligomerization, or other types of clustering of signaling proteins as a key step in the signaling cascade. However, it is often experimentally challenging to directly observe and characterize the molecular mechanisms such interactions-the greatest difficulty lies in the fact that living cells have an unknown number of background processes that may or may not participate in the molecular process of interest, and as a consequence, it is usually impossible to definitively correlate an observation to a well-defined cellular mechanism. One of the experimental methods that can quantitatively capture these interactions is through membrane reconstitution, whereby a lipid bilayer is fabricated to mimic the membrane environment, and the biological components of interest are systematically introduced, without unknown background processes. This configuration allows the extensive use of fluorescence techniques, particularly fluorescence fluctuation spectroscopy and single-molecule fluorescence microscopy. In this review, we describe how the equilibrium diffusion of two proteins, K-Ras4B and the PH domain of Bruton's tyrosine kinase (Btk), on fluid lipid membranes can be used to determine the kinetics of homodimerization reactions.

• Molecules and Cells
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• v.45 no.9
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• pp.603-609
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• 2022

Cells can communicate in a variety of ways, such as by contacting each other or by secreting certain factors. Recently, extracellular vesicles (EVs) have been proposed to be mediators of cell communication. EVs are small vesicles with a lipid bilayer membrane that are secreted by cells and contain DNA, RNAs, lipids, and proteins. These EVs are secreted from various cell types and can migrate and be internalized by recipient cells that are the same or different than those that secrete them. EVs harboring various components are involved in regulating gene expression in recipient cells. These EVs may also play important roles in the senescence of cells and the accumulation of senescent cells in the body. Studies on the function of EVs in senescent cells and the mechanisms through which nonsenescent and senescent cells communicate through EVs are being actively conducted. Here, we summarize studies suggesting that EVs secreted from senescent cells can promote the senescence of other cells and that EVs secreted from nonsenescent cells can rejuvenate senescent cells. In addition, we discuss the functional components (proteins, RNAs, and other molecules) enclosed in EVs that enter recipient cells.

• Molecules and Cells
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• v.45 no.3
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• pp.158-167
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• 2022

Ubiquitin (Ub) is post-translationally modified by Ub itself or Ub-like proteins, phosphorylation, and acetylation, among others, which elicits a variety of Ub topologies and cellular functions. However, N-terminal (Nt) modifications of Ub remain unknown, except the linear head-to-tail ubiquitylation via Nt-Met. Here, using the yeast Saccharomyces cerevisiae and an Nt-arginylated Ub-specific antibody, we found that the detectable level of Ub undergoes Nt-Met excision, Nt-deamination, and Nt-arginylation. The resulting Nt-arginylated Ub and its conjugated proteins are upregulated in the stationary-growth phase or by oxidative stress. We further proved the existence of Nt-arginylated Ub in vivo and identified Nt-arginylated Ub-protein conjugates using stable isotope labeling by amino acids in cell culture (SILAC)-based tandem mass spectrometry. In silico structural modeling of Nt-arginylated Ub predicted that Nt-Arg flexibly protrudes from the surface of the Ub, thereby most likely providing a docking site for the factors that recognize it. Collectively, these results reveal unprecedented Nt-arginylated Ub and the pathway by which it is produced, which greatly expands the known complexity of the Ub code.

• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.65-70
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• 2011

Development of mouse fetus brains can be defined morphologically and functionally by three developmental stages, embryo day (ED) 16, postnatal stage one week and eight weeks. These defined stages of brain development may be closely associated with differential gene expression rates due to limited cellular resources such as energy, space, and free water. Complex patterns of expressed genes and proteins during brain development suggests the changes in relative concentrations of proteins rather than the increase in numbers of new gene products. This study was designed to evaluate early protein expression pattern in mouse fetus brain. The mouse brain proteome of fetus at ED 15.5, and 19.5 was obtained using 2-dimensional gel electrophoresis (DE). Analysis of the 2-DE gels in pH 3-10 range revealed the presence of 15 differentially expressed spots, of which 11 spots were identified to be known proteins following MALDI-TOF analysis; 3 spots were up-regulated and 8 spots were down-regulated in the mouse fetus brain at ED 15.5. UP-regulated proteins were identified as MCG18238, isoform M2 of pyruvate kinase isozymes M1/M2, isoform 2 of heterogeneous nuclear ribonucleoprotein K, heterogeneous nuclear ribonucleoprotein H2, creatine kinase B-type, 40S ribosomal protein SA and hemoglobin subunit beta-H1. Down-regulated proteins were putative uncharacterized protein, lactoylglutathione lyase and secreted acidic cysteine rich glycoprotein. Our results revealed composite profiles of mouse fetus brain proteins related to mouse fetus development by 2-DE analysis implying possible roles of these proteins in neural differentiation.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.191-201
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• 2008

Bacillus sp. SB-007 was isolated from pea leaves harvested from the southwestern parts of South Korea through screening on a minimal medium containing 0.2% purified cutin for its ability to induce the cutinase production. However, no cutinase was produced when it was grown in a minimal medium containing 0.2% glucose. A proteomic approach was applied to separate and characterize these differentially secreted proteins. The expression level of 83 extracellular proteins of the cutinase-producing Bacillus sp. strain SB-007 incubated in a cutinase-induced medium increased significantly as compared with that cultured in a non cutinase-induced medium containing glucose. The extracellular proteome of Bacillus sp. SB-007 includes proteins from different functional classes, such as enzymes for the degradation of various macromolecules, proteins involved in energy metabolism, sporulation, transport/binding proteins and lipoproteins, stress inducible proteins, several cellular molecule biosynthetic pathways and catabolism, and some proteins with an as yet unknown function. In addition, the two protein spots showed little similarities with the known lipolytic enzymes in the database. These secreted proteome analysis results are expected to be useful in improving the Bacillus strains for the production of industrial cutinases.

• YAKHAK HOEJI
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• v.54 no.3
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• pp.180-186
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• 2010

Aldosterone, mineralocorticoid hormone, has important functions related to the regulation of blood pressure and balance of fluids and electrolytes in the distal region of the nephron. By genomic and non-genomic action of aldosterone, the physiological kidney functions are modulated. However, many of them except several kind of sodium channel have not been identified and analyzed yet. In this study, proteomic technologies with two-dimensional gel electrophoresis (2-DE) gel using aldosterone rat model were applied to analyze and identify the aldosterone dependently expressed proteins in rat kidney cortex. As a result, the established aldosterone rat model exhibited the normal physiological responses to aldosterone and modulated proteins were identified, which included 15 increased and 3 decreased proteins on 2-DE analysis. Among them, 11 proteins were identified as changed proteins by LC-MS/MS analysis. These proteins identified as aldosterone induced proteins were involved in several cellular pathways such as cytoskeleton remodeling, energy metabolism, amino acid metabolism, and chaperone process. In conclusion, our data could provide the insights into the new mechanism underlying regulation of kidney functions by aldosterone.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.247-253
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• 2002

The cellular responses of TNT-degrading bacterium, Stenotrophomonas sp. OK-5 to explosive 2,4,6-trini-trotoluene (TNT) as an environmental contaminant were examined. Survival of the strain OK-5 with time in the presence of different concentrations of TNT under sublethal conditions was monitored, and viable counts paralleled the production of the stress shock proteins in this bacterium. Total cellular fatty acids analysis showed that strain OK-5 produced or disappeared several different kinds of lipids when grown on TNT media than when grown on TSA. Under scanning electron microscope, the cells treated with 0.5 mM TNT for 12 hrs showed irregular rod shapes with wrinkled surfaces. Analyses of SDS-PAGE and Western blot using anti-DnaK and anti-GroEL revealed that several stress shock proteins including 70 kDa DnaK and 60 kDa GroEL in strain OK-5 were newly synthesized at different TNT concentrations in exponentially growing cultures. 2-D PAGE of soluble protein fractions from the culture of OK-5 exposed to TNT demonstrated that approximately 300 spots were observed on the silver stained gel ranging from pH 3 to pH 10. Among them, 10 spots significantly induced and expressed in response to TNT were selected and analyzed. As the result of internal amino acid sequencing with ESI-Q TOF, two proteins, spot #1 and spot #10 were assigned the DnaK protein XF2340 of Xylella fastidiosa and stress-induced protein of Mesorhizobium loti, respectively.