1.Ubiquitylation of Fe65 adaptor protein by neuronal precursor cell expressed developmentally down regulated 4-2 (Nedd4-2) via the WW domain interaction with Fe65.
Eun Jeoung LEE ; Sunghee HYUN ; Jaesun CHUN ; Sung Hwa SHIN ; Sang Sun KANG
Experimental & Molecular Medicine 2009;41(8):555-568
Fe65 has been characterized as an adaptor protein, originally identified as an expressed sequence tag (EST) corresponding to an mRNA expressed at high levels in the rat brain. It contains one WW domain and two phosphotyrosine interaction/phosphotyrosine binding domains (PID1/PID2). As the neuronal precursor cell expressed developmentally down regulated 4-2 (Nedd4-2) has a putative WW domain binding motif (72PPLP75) in the N-terminal domain, we hypothesized that Fe65 associates with Nedd4-2 through a WW domain interaction, which has the characteristics of E3 ubiquitin-protein ligase. In this paper, we present evidence for the interaction between Fe65 WW domain and Nedd4-2 through its specific motif, using a pull down approach and co-immunoprecipitation. Additionally, the co-localization of Fe65 and Nedd4-2 were observed via confocal microscopy. Co-localization of Fe65 and Nedd4-2 was disrupted by either the mutation of Fe65 WW domain or its putative binding motif of Nedd4-2. When the ubiquitin assay was performed, the interaction of Nedd4-2 (wt) with Fe65 is required for the cell apoptosis and the ubiquitylation of Fe65. We also observed that the ubiquitylation of Fe65 (wt) was augmented depending on Nedd4-2 expression levels, whereas the Fe65 WW domain mutant (W243KP245K) or the Nedd4-2 AL mutant (72PPLP75 was changed to 72APLA75) was under-ubiquitinated significantly. Thus, our observations implicated that the protein-protein interaction between the WW domain of Fe65 and the putative binding motif of Nedd4-2 down-regulates Fe65 protein stability and subcellular localization through its ubiquitylation, to contribute cell apoptosis.
Adaptor Proteins, Signal Transducing/chemistry/genetics/*metabolism
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Cell Line
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*Down-Regulation
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Endosomal Sorting Complexes Required for Transport/genetics/*metabolism
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*Gene Expression Regulation, Developmental
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Humans
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Immunoprecipitation
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Microscopy, Confocal
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Mutation
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Protein Interaction Mapping
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Protein Structure, Tertiary/*physiology
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Transfection
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Ubiquitin-Protein Ligases/genetics/*metabolism
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Ubiquitination
2.Human skeletal dysplasia caused by a constitutive activated transient receptor potential vanilloid 4 (TRPV4) cation channel mutation.
Sang Sun KANG ; Sung Hwa SHIN ; Chung Kyoon AUH ; Jaesun CHUN
Experimental & Molecular Medicine 2012;44(12):707-722
The transient receptor potential vanilloid 4 (TRPV4) cation channel, a member of the TRP vanilloid subfamily, is expressed in a broad range of tissues where it participates in the generation of Ca2+ signals and/or depolarization of the membrane potential. Regulation of TRPV4 abundance at the cell surface is critical for osmo- and mechanotransduction. Defects in TRPV4 are the cause of several human diseases, including brachyolmia type 3 (MIM:113500) (also known as brachyrachia or spondylometaphyseal dysplasia Kozlowski type [MIM:118452]), and metatropic dysplasia (MIM:156530) (also called metatropic dwarfism or parastremmatic dwarfism [MIM:168400]). These bone dysplasia mutants are characterized by severe dwarfism, kyphoscoliosis, distortion and bowing of the extremities, and contractures of the large joints. These diseases are characterized by a combination of decreased bone density, bowing of the long bones, platyspondyly, and striking irregularities of endochondral ossification with areas of calcific stippling and streaking in radiolucent epiphyses, metaphyses, and apophyses. In this review, we discuss the potential effect of the mutation on the regulation of TRPV4 functions, which are related to human diseases through deviated function. In particular, we emphasize how the constitutive active TRPV4 mutant affects endochondral ossification with a reduced number of hypertrophic chondrocytes and the presence of cartilage islands within the zone of primary mineralization. In addition, we summarize current knowledge about the role of TRPV4 in the pathogenesis of several diseases.
Humans
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*Mutation
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Osteochondrodysplasias/*genetics
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Osteogenesis/genetics
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TRPV Cation Channels/chemistry/*genetics/metabolism
3.Results of the Patch Test (T.R.U.E. Test) in Patients withAllergic Contact Dermatitis (2005~2010, Kangwon, Yeongseo Province).
Geun Dong SUL ; Sung yul LEE ; Jae Hong KIM ; Hannah HONG ; Jaesun CHUN ; Sung Ku AHN
Korean Journal of Dermatology 2011;49(7):572-578
BACKGROUND: Since 2005, the commercial patch test panel, the TRUE-test, has been available. However, there have been no reports regarding the results of the TRUE-test compared with previously used Korean Standard Series in Korea. OBJECTIVE: This study aimed to evaluate the prevalence of the contact allergy, causative allergens, and source of allergens in patients who were diagnosed with allergic contact dermatitis, and to compare the findings with previously used Korean Standard Series. METHODS: We reviewed the results of the TRUE-test from 2005~2010 in Wonju Christian Hospital. We patch-tested 843 patients who were diagnosed with allergic contact dermatitis. The patch test reading was performed on day 2 and days 3 or 4, according to the patients' needs. Epidemiologic findings of patients and the results of the patch tests were analyzed. RESULTS: A total of 843 patch-tested cases were compiled and analyzed. Of 843 patch-tested patients (male, 309; female, 534), 65.8% had at least 1 positive reaction and 30.2% at least 2 positive reactions. The highest age distribution was the 5th decade in females. The face, with the exception of the eyelids, ears, and lips, was the most frequently affected site (comprising 50.3%). The highest sensitization rates were found with nickel (29.1%), thiomersal (10.9%), and cobalt dichloride (9.7%). The lowest positivity included caine mix (0.7%), mercaptobenzothiazole (1.2%), and quinolone mix (1.2%). Metal allergens displayed higher positive rates than any other standard allergens. The overall prevalence was similar with a recent report in Korea. CONCLUSION: There was no significant difference in the overall prevalence of the most sensitized allergen compared with the reports about previously used Korean standard series.
Age Distribution
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Allergens
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Cobalt
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Dermatitis, Allergic Contact
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Dermatitis, Contact
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Ear
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Eyelids
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Female
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Humans
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Hypersensitivity
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Lip
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Nickel
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Patch Tests
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Prevalence
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Thimerosal
4.Preventive Effects of Multi-Lamellar Emulsion on Low Potency Topical Steroid Induced Local Adverse Effect.
Geun Dong SUL ; Hyun Jung PARK ; Jong Hwan BAE ; Keum Duck HONG ; Byeong Deog PARK ; Jaesun CHUN ; Se Kyoo JEONG ; Seung Hun LEE ; Sung Ku AHN ; Hyun Jung KIM
Annals of Dermatology 2013;25(1):5-11
BACKGROUND: Topical steroid treatment induces diverse local Wand systemic adverse effects. Several approaches have been tried to reduce the steroid-induced adverse effects. Simultaneous application of physiological lipid mixture is also suggested. OBJECTIVE: Novel vehicles for topical glucocorticoids formulation were evaluated for the efficacy of reducing side-effects and the drug delivery properties of desonide, a low potency topical steroid. METHODS: Transcutaneous permeation and skin residual amount of desonide were measured using Franz diffusion cells. The in vivo anti-inflammatory activity was evaluated using murine model. RESULTS: Topical steroids formulation containing desonide, in either cream or lotion form, were prepared using multi-lamellar emulsion (MLE), and conventional desonide formulations were employed for comparison. MLE formulations did not affect the anti-inflammatory activity of the desonide in phobol ester-induced skin inflammation model, compared with conventional formulations. While the penetrated amounts of desonide were similar for all the tested formulations at 24 hours after application, the increased lag time was observed for the MLE formulations. Interestingly, residual amount of desonide in epidermis was significantly higher in lotion type MLE formulation. Steroid-induced adverse effects, including permeability barrier function impairment, were partially prevented by MLE formulation. CONCLUSION: Topical desonide formulation using MLE as a vehicle showed a better drug delivery with increased epidermal retention. MLE also partially prevented the steroid-induced side effects, such as skin barrier impairment.
Desonide
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Diffusion
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Epidermis
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Glucocorticoids
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Inflammation
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Permeability
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Retention (Psychology)
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Skin
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Steroids