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

Mol Biol Cell. 2002 Sep;13(9):3344-54. doi: 10.1091/mbc.e01-10-0094.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Calcium / pharmacology
  • Cattle
  • Chromatography
  • Chromatography, Gel / methods*
  • Cytosol / metabolism*
  • Dose-Response Relationship, Drug
  • Durapatite / pharmacology
  • Exocytosis
  • Glutathione Transferase / metabolism
  • Humans
  • Male
  • Mass Spectrometry
  • Mast Cells / metabolism*
  • Molecular Sequence Data
  • Nerve Tissue Proteins / chemistry*
  • Nerve Tissue Proteins / isolation & purification*
  • Plasmids / metabolism
  • Proteins / chemistry*
  • Proteins / isolation & purification*
  • Rats
  • Rats, Sprague-Dawley
  • Recombinant Fusion Proteins / metabolism
  • Sepharose / analogs & derivatives*
  • Sepharose / pharmacology
  • Sequence Homology, Amino Acid
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Time Factors


  • Nerve Tissue Proteins
  • Proteins
  • Recombinant Fusion Proteins
  • SCRN1 protein, human
  • phenyl-superose
  • secernin 1 protein, mouse
  • Sepharose
  • Durapatite
  • Superose 12
  • Glutathione Transferase
  • Calcium