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Purification and identification of secernin, a novel cytosolic protein that regulates exocytosis in mast cells.

ABSTRACT: After permeabilization with the pore-forming toxin streptolysin-O mast cells can be triggered to secrete by addition of both calcium and a GTP analogue. If stimulation is delayed after permeabilization, there is a progressive decrease in the extent of secretion upon stimulation, eventually leading to a complete loss of the secretory response. This loss of secretory response can be retarded by the addition of cytosol from other secretory tissues, demonstrating that the response is dependent on a number of cytosolic proteins. We have used this as the basis of a bioassay to purify Secernin 1, a novel 50-kDa cytosolic protein that appears to be involved in the regulation of exocytosis from peritoneal mast cells. Secernin 1 increases both the extent of secretion and increases the sensitivity of mast cells to stimulation with calcium.

SUBMITTER: Way G

PROVIDER: S-EPMC124164 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature

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Purification and identification of secernin, a novel cytosolic protein that regulates exocytosis in mast cells.

Way Gemma G Morrice Nicholas N Smythe Carl C O'Sullivan Antony J AJ

Molecular biology of the cell 20020901 9

After permeabilization with the pore-forming toxin streptolysin-O mast cells can be triggered to secrete by addition of both calcium and a GTP analogue. If stimulation is delayed after permeabilization, there is a progressive decrease in the extent of secretion upon stimulation, eventually leading to a complete loss of the secretory response. This loss of secretory response can be retarded by the addition of cytosol from other secretory tissues, demonstrating that the response is dependent on a ...[more]

PMID: 12221138

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