TRESK is the most recently reported two-pore domain K^＋ channel, and different from other two-pore domain channels in gene, molecular structure, electrophysiological and pharmacological properties. Although the curre...TRESK is the most recently reported two-pore domain K^＋ channel, and different from other two-pore domain channels in gene, molecular structure, electrophysiological and pharmacological properties. Although the current knowledge of this potassium channel is inadequate, researches have demonstrated that TRESK is remarkablely linked to acute and chronic pain by activation of calcineurin. The fact that TRESK is sensitive to volatile anesthetics and localization in central nerve system implies that TRESK may play a very important role in the mechanism mediating general anesthesia. The further research of TRESK may contribute to explore the underlying mechanism of some pathological conditions and yield novel treatments for some diseases.展开更多
Potassium is one of the major macro-nutrients essential for a number of cellular processes in plants. Low potassium level in the soil represents a limiting factor for crop production. Recent studies have identified po...Potassium is one of the major macro-nutrients essential for a number of cellular processes in plants. Low potassium level in the soil represents a limiting factor for crop production. Recent studies have identified potassium transporters that are involved in potassium acquisition, and some of them are critical for potassium nutrition under low potassium conditions. However, little is understood on the molecular components involved in low potassium signaling and responses. We report here the identification ofa calcineurin B-like protein-interacting protein kinase （CIPK9） as a critical regulator of low potassium response in ,Arabidopsis. The CIPK9 gene was responsive to abiotic stress conditions, and its transcript was inducible in both roots and shoots by potassium deprivation. Disruption of CIPK9 function rendered the mutant plants hypersensitive to low potassium media. Further analysis indicated that K^＋ uptake and content were not affected in the mutant plants, implying CIPK9 in the regulation of potassium utilization or sensing processes.展开更多
Calcineurin dephosphorylates multiple serine residues near the N terminus of NFAT proteins enabling them to translocate from cytoplasm to nucleus, where they activate a subset of hypertrophic response genes. Transgeni...Calcineurin dephosphorylates multiple serine residues near the N terminus of NFAT proteins enabling them to translocate from cytoplasm to nucleus, where they activate a subset of hypertrophic response genes. Transgenic mice over-expressing a constitu- tively active form of calcineurin or NFAT3, developed obviously hypertrophy and heart failure or sudden death proving its pathogenic role. Here we used literatures on MEDLINE （2000-2011）, systematically reviewed the new development of calcineurin signaling pathway in myocardial hypertrophy展开更多
RCAN1, also known as DSCR1, is an endogenous regulator of calcineurin, a serine/threonine protein phosphatase that plays a critical role in many physiological processes. In this report, we demonstrate that p38a MAP ki...RCAN1, also known as DSCR1, is an endogenous regulator of calcineurin, a serine/threonine protein phosphatase that plays a critical role in many physiological processes. In this report, we demonstrate that p38a MAP kinase can phosphorylate RCAN1 at multiple sites in vitro and show that phospho-RCAN1 is a good protein substrate for calcineurin. In addition, we found that unphosphorylated RCANI noncompetitively inhibits calcineurin protein phosphatase activity and that the phosphorylation of RCAN1 by p38a MAP kinase decreases the binding affinity of RCAN1 for calcineurin. These findings reveal the molecular mechanism by which p38a MAP kinase regulates the function of RCAN1/calcineurin through phosphorylation.展开更多
The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineur...The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations.展开更多
基金This work was supported by the National Natural Science Foundation of China （No. 30672020）；the B. Braun Anesthesia Foundation of B. Braun Medical （Shanghai） International Trading Co., Ltd.
文摘TRESK is the most recently reported two-pore domain K^＋ channel, and different from other two-pore domain channels in gene, molecular structure, electrophysiological and pharmacological properties. Although the current knowledge of this potassium channel is inadequate, researches have demonstrated that TRESK is remarkablely linked to acute and chronic pain by activation of calcineurin. The fact that TRESK is sensitive to volatile anesthetics and localization in central nerve system implies that TRESK may play a very important role in the mechanism mediating general anesthesia. The further research of TRESK may contribute to explore the underlying mechanism of some pathological conditions and yield novel treatments for some diseases.
基金a grant from the National Science Foundation （USA） （to SL）.
文摘Potassium is one of the major macro-nutrients essential for a number of cellular processes in plants. Low potassium level in the soil represents a limiting factor for crop production. Recent studies have identified potassium transporters that are involved in potassium acquisition, and some of them are critical for potassium nutrition under low potassium conditions. However, little is understood on the molecular components involved in low potassium signaling and responses. We report here the identification ofa calcineurin B-like protein-interacting protein kinase （CIPK9） as a critical regulator of low potassium response in ,Arabidopsis. The CIPK9 gene was responsive to abiotic stress conditions, and its transcript was inducible in both roots and shoots by potassium deprivation. Disruption of CIPK9 function rendered the mutant plants hypersensitive to low potassium media. Further analysis indicated that K^＋ uptake and content were not affected in the mutant plants, implying CIPK9 in the regulation of potassium utilization or sensing processes.
文摘Calcineurin dephosphorylates multiple serine residues near the N terminus of NFAT proteins enabling them to translocate from cytoplasm to nucleus, where they activate a subset of hypertrophic response genes. Transgenic mice over-expressing a constitu- tively active form of calcineurin or NFAT3, developed obviously hypertrophy and heart failure or sudden death proving its pathogenic role. Here we used literatures on MEDLINE （2000-2011）, systematically reviewed the new development of calcineurin signaling pathway in myocardial hypertrophy
基金supported in part by Ministry of Science and Technology of China (Grant 2011CB910803)
文摘RCAN1, also known as DSCR1, is an endogenous regulator of calcineurin, a serine/threonine protein phosphatase that plays a critical role in many physiological processes. In this report, we demonstrate that p38a MAP kinase can phosphorylate RCAN1 at multiple sites in vitro and show that phospho-RCAN1 is a good protein substrate for calcineurin. In addition, we found that unphosphorylated RCANI noncompetitively inhibits calcineurin protein phosphatase activity and that the phosphorylation of RCAN1 by p38a MAP kinase decreases the binding affinity of RCAN1 for calcineurin. These findings reveal the molecular mechanism by which p38a MAP kinase regulates the function of RCAN1/calcineurin through phosphorylation.
基金supported by the National Important Novel Medicine Research Project (2012ZX09304010, 2013ZX09102062)the National Natural Science Foundation of China (31270849)
文摘The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations.
