Babar, Sheikh Md. Enayetul Song, Eun Joo Yoo, Young Sook 2024-01-21T00:00:24Z 2024-01-21T00:00:24Z 2022-01-10 2008-02 1615-9306 https://pubs.kist.re.kr/handle/201004/133760 Reversible protein phosphorylation and dephosphorylation are very important activities in understanding cellular signaling networks. In this paper we described a CE-LIF-based assay method of calcineurin (CN), a protein phosphatase important in cardiac hypertrophy, in which a fluorescence-labeled 19-amino acid phosphopeptide was used as a substrate. The substrate was converted to a dephosphorylated product by CN and both the substrate and product were detected by the LIF detector. This assay method was tested for various separation parameters as well as reaction parameters. It was found that 100 mM of a boric acid buffer with a pH of 9.00 produced optimum separation at 10 kV of applied voltage using a 47 cm capillary. After obtaining the suitable reaction conditions the method was used to detect and quantify the CN activity in HL-1 cell extracts where the picogram level of CN activity was obtained Per microgram total protein. It was also observed that immunosuppressive drugs like okadaic acid and cyclosporine A inhibit in vitro CN activity. English WILEY-V C H VERLAG GMBH DEPENDENT PROTEIN PHOSPHATASE ALKALINE-PHOSPHATASE CALMODULIN PHOSPHORYLATION INHIBITION ASSAY ELECTROCHROMATOGRAPHY DEPHOSPHORYLATION OVEREXPRESSION CHROMATOGRAPHY Analysis of calcineurin activity by capillary electrophoresis with laser-induced fluorescence detection using peptide substrate Article 10.1002/jssc.200700326 1 JOURNAL OF SEPARATION SCIENCE, v.31, no.3, pp.579 - 587 JOURNAL OF SEPARATION SCIENCE 31 3 579 587 scie scopus 000253689700017 2-s2.0-40449098337 Chemistry, Analytical Chemistry Article DEPENDENT PROTEIN PHOSPHATASE ALKALINE-PHOSPHATASE CALMODULIN PHOSPHORYLATION INHIBITION ASSAY ELECTROCHROMATOGRAPHY DEPHOSPHORYLATION OVEREXPRESSION CHROMATOGRAPHY calcineurin capillary electrophoresis cardiac hypertrophy