Effect of dominant negative SNAP-23 expression on platelet function.
BACKGROUND
The protein SNAP-23 is part of the secretory pathway in platelets. It is, however, not entirely clear to what extent this protein contributes to the secretory function of platelets. Therefore, we overexpressed a dominant negative mutant with a novel technology that allows the creation of intact transgene-expressing platetets.


RESULTS
Overexpression of a dominant negative SNAP-23 mutant that inhibited the binding of the native protein to the docking site within the secretory machinery resulted in significant suppression of the agonist-dependent surface recruitment of P-selectin and CD40L. Simultaneously, release from dense granules was clearly suppressed in the presence of this construct. Also agonist-dependent surface expression of fibrinogen receptor markers CD41 and CD61 was reduced, and agonist-triggered aggregation was inhibited.


CONCLUSIONS
The dominant negative inhibition of SNAP-23 resulted in clear effects on platelet functions. The novel method using recombinant culture-derived platelets allowed the rapid clarification of the functional importance of this protein in intact platelets.
Gillitzer
A
A
Trigen AG, Martinsried, Germany.
Peluso
M
M
Bültmann
A
A
Münch
G
G
Gawaz
M
M
Ungerer
M
M
D001792:Blood Platelets / Q000378:metabolism* / Q000502:physiology; D023201:CD40 Ligand; D002478:Cells, Cultured; D015870:Gene Expression; D006801:Humans; D039661:Integrin beta3; D050505:Mutant Proteins; D019007:P-Selectin; D010974:Platelet Aggregation; D040201:Platelet Membrane Glycoprotein IIb; D050766:Qb-SNARE Proteins / Q000235:genetics* / Q000502:physiology; D050767:Qc-SNARE Proteins / Q000235:genetics* / Q000502:physiology; D055571:Secretory Pathway; D014162:Transfection
D039661:Integrin beta3; D050505:Mutant Proteins; D019007:P-Selectin; D040201:Platelet Membrane Glycoprotein IIb; D050766:Qb-SNARE Proteins; D050767:Qc-SNARE Proteins; C100493:SNAP23 protein, human; D023201:CD40 Ligand