Article

Purification and functional analysis of a Rab27 effector munc 13-4 using a semi-intact platelet dense-granule secretion assay.

Methods in Enzymology (Impact Factor: 2.19). 02/2005; 403:778-88. DOI: 10.1016/S0076-6879(05)03067-3
Source: PubMed

ABSTRACT We have demonstrated that small GTPase Rab27 regulates dense-granule secretion in platelets. Using Rab27a affinity chromatography, we purified Munc 13-4 as a novel Rab27a interacting protein from platelet cytosol. This chapter describes the purification of Munc 13-4 and an in vitro assay system analyzing the mechanism of dense-granule secretion in platelets. The activity of Munc 13-4 is tested in this assay.

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