Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.16 (calcineurin)
 17,112 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have used a monoclonal antibody (MAb E12), one of several such antibodies raised against theophylline-treated Necturus gallbladder epithelial cells, to isolate a chloride channel protein by the use of an immunoaffinity column and FPLC. This protein (M(r) 219,000) has been reconstituted into a planar lipid bilayer, where it behaves as a chloride-selective channel (PCl/PNa = 20.2; PNa/PK = 1) whose unit conductance is 62.4 +/- 4.6 pS. Antibody added to the trans side (there is no effect from the cis side) causes channel open probability to drop to virtually zero, but has no effect on the conductance or the selectivity of single channels. To test the role of phosphorylation in the activity of the native channel, we studied the effects of the protein phosphatase inhibitor okadaic acid (OA) on intact gallbladders, and showed that channels opened by theophylline treatment and closed by antibody are reopened reversibly by OA (0.01-1.0 microM). Addition of the catalytic subunit of protein phosphatase 2A (PP-2A) to the cis side of a bilayer containing reconstituted chloride channels caused closure of the channels after a delay, and subsequent addition of ATP and the catalytic subunit of cAMP-dependent protein kinase (PKA) caused immediate reopening. These data indicate that (a) this chloride channel protein inserts in a directed way into the bilayer such that the cis side is 'intracellular', (b) the purified channel protein is phosphorylated, and (c) gating from the cellular side is controlled by the direct phosphorylation and dephosphorylation of the channel protein.
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PMID:Reconstitution and regulation of an epithelial chloride channel. 133 26

Forty new NotI linking clones representing sequence tagged sites (STSs) were mapped by fluorescence in situ hybridization (FISH) to different regions of human chromosome 3 (HSA3). Clone NL1-245, containing human aminoacylase 1, was localized to 3p21.2-p21.1. Our previous localization of the CLC-2 chloride channel protein gene was refined to 3q27. Clone NL2-316 most likely contains a translocon-associated protein gamma-subunit gene and was mapped to 3q23-q24. To our knowledge, this is the first time this gene has been mapped. One NotI linking clone (NL1-229) probably contains a new protein phosphatase gene. This clone was mapped to 3p25. Five NotI linking clones probably contain human expressed sequence tags (ESTs), as they possess sequences with a high level of identity (> 90%) to cDNA clones. Other clones show 56-85% homology to known mammalian and human genes with various functions, including oncogenes and tumour-suppressor genes. These clones might represent new genes.
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PMID:Human chromosome 3: high-resolution fluorescence in situ hybridization mapping of 40 unique NotI linking clones homologous to genes and cDNAs. 888 43