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981.
Yon Soo Jeong 《Channels (Austin, Tex.)》2016,10(3):214-224
Anion exchanger 2 (AE2) has a critical role in epithelial cells and is involved in the ionic homeostasis such as Cl? uptake and HCO3? secretion. However, little is known about the regulatory mechanism of AE2. The main goal of the present study was to investigate potential regulators, such as spinophilin (SPL), inositol-1,4,5-trisphosphate [IP3] receptors binding protein released with IP3 (IRBIT), STE20/SPS1-related proline/alanine-rich kinase (SPAK) kinase, and carbonic anhydrase XII (CA XII). We found that SPL binds to AE2 and markedly increased the Cl?/HCO3? exchange activity of AE2. Especially SPL 1–480 domain is required for enhancing AE2 activity. For other regulatory components that affect the fidelity of fluid and HCO3? secretion, IRBIT and SPAK had no effect on the activity of AE2 and no protein-protein interaction with AE2. It has been proposed that CA activity is closely associated with AE activity. In this study, we provide evidence that the basolateral membrane-associated CA isoform CA XII significantly increased the activity of AE2 and co-localized with AE2 to the plasma membrane. Collectively, SPL and CA XII enhanced the Cl?/HCO3? exchange activity of AE2. The modulating action of these regulatory proteins could serve as potential therapeutic targets for secretory diseases mediated by AE2. 相似文献
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983.
984.
985.
986.
Ho Shin Kim Van-Hai Hoang Mannkyu Hong Kyung Chul Kim Jihyae Ann Cong-Truong Nguyen Ji Hae Seo Hoon Choi Jun Yong Kim Kyu-Won Kim Woong Sub Byun Sangkook Lee Seungbeom Lee Young-Ger Suh Jie Chen Hyun-Ju Park Tae-Min Cho Ji Young Kim Jeewoo Lee 《Bioorganic & medicinal chemistry》2019,27(7):1370-1381
On the basis of deguelin, a series of the B,C-ring truncated surrogates with N-substituted amide linkers were investigated as HSP90 inhibitors. The structure activity relationship of the template was studied by incorporating various substitutions on the nitrogen of the amide linker and examining their HIF-1α inhibition. Among them, compound 57 showed potent HIF-1α inhibition and cytotoxicity in triple-negative breast cancer lines in a dose-dependent manner. Compound 57 downregulated expression and phosphorylation of major client proteins of HSP90 including AKT, ERK and STAT3, indicating that its antitumor activity was derived from the inhibition of HSP90 function. The molecular modeling of 57 demonstrated that 57 bound well to the C-terminal ATP-binding pocket in the open conformation of the hHSP90 homodimer with hydrogen bonding and pi-cation interactions. Overall, compound 57 is a potential antitumor agent for triple-negative breast cancer as a HSP90 C-terminal inhibitor. 相似文献
987.
Nguyen Thu Thi Hwang In Yeub Na Jeong Geol Lee Eun Yeol 《Journal of industrial microbiology & biotechnology》2019,46(5):675-685
Journal of Industrial Microbiology & Biotechnology - Propane is the main component of liquefied petroleum gas and is derived from crude oil processing. Methanotrophic bacteria can convert... 相似文献
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989.
Root explants excised from carnation plants maintained in vitro formed off-white, friable calluses after three weeks of culture
on Murashige and Skoog (MS) medium supplemented with 1 mg l−1 thidiazuron (TDZ) and 1 mg l−1 α-naphthalaneacetic acid (NAA). These calluses were subsequently transferred to MS basal medium where, after an additional
four weeks of culture, approximately 50% of the calluses formed somatic embryos. However, calluses formed on root explants
that had been cultured on MS medium supplemented with 2,4-dichlorophenoxyacetic acid did not produce somatic embryos upon
transfer to MS basal medium. Somatic embryos developed into plantlets and subsequently were grown to maturity. These results
indicate that root explants have a high competence for somatic embryogenesis in carnation.
J. Seo and S.W. Kim contributed equally to this work. 相似文献
990.
Lee J Kim H Jeong JC Park ES Hwang KW Yang SJ Jeong JH 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,859(2):229-233
A simple, rapid, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for quantification of beraprost, a stable, orally active prostacyclin analogue with vasodilatory, antiplatelet and cytoprotective effects. The analyte and internal standard, indomethacin, were extracted by solid-phase extraction using OASIS HLB cartridge. The chromatographic separation was performed on a C18 column with a mobile of 0.1% formic acid-methanol (30:70, v/v). The highest daughter ion of deprotonated analyte was quantitated in negative ionization by multiple reactions monitoring with a mass spectrometer. The mass transitions m/z 397>269 and m/z 356>312 were used to measure beraprost and internal standard, respectively. The assay exhibited a linear range from 0.02 to 2 ng/mL for beraprost in human plasma. The lower limit of quantitation was 20 pg/mL with a relative standard deviation of less than 20%. The method was validated with respect to linearity, sensitivity, specificity, recovery, accuracy and precision. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic study. 相似文献