Calcium-activated chloride channel involved in human sweat formation

An in vitro method of identifying an inhibitor of sweat formation, comprising the steps of:

• a) contacting a secretory sweat gland cell comprising
• (i) a calcium-activated chloride channel, wherein the calcium-activated chloride channel is the human TMEM16A encoded by a nucleic acid molecule encoding a protein capable of forming a calcium-activated chloride channel, wherein said nucleic acid molecule comprises or consists of
• (a) a nucleic acid molecule encoding a protein having the amino acid sequence of SEQ ID NO:1;
• (b) a nucleic acid molecule having the DNA sequence of SEQ ID NO:2;
• (c) a nucleic acid molecule having the sequence of SEQ ID NO:2, wherein each thymine is replaced by uracil;
• (d) a nucleic acid molecule encoding a protein having at least 97% sequence identity to the protein of (a);
• or
• (e) a nucleic acid molecule that is degenerate with respect to the nucleic acid molecule of (b), or (c);
• and
• (ii) a halide-sensitive cytoplasmic indicator protein;
• with a test compound;
• b) adding to the cells of (a):
• b-i) a calcium-elevating agonist;
• and
• b-ii) a halide;
• c) determining the amount of chloride secretion from the secretory sweat gland cell after the contacting with the test compound and the addition of the calcium-elevating agonist and iodide, wherein the amount of chloride secretion is determined based on an alteration of the signal emitted from the halide-sensitive cytoplasmic indicator protein;
• and
• d) comparing the amount of chloride secretion from the secretory sweat gland cell determined in step (c) with the amount of chloride secretion from the secretory sweat gland cell in the absence of the test compound, wherein a decrease in the amount of chloride secretion determined in (c) as compared to the amount of chloride secretion in the absence of the test compound indicates that the test compound is an inhibitor of sweat formation.