A 20-nm step toward the cell membrane preceding exocytosis may correspond to docking of tethered granules.
Karatekin E, Tran VS, Huet S, Fanget I, Cribier S, Henry JP, Biophys J, 2008 Apr 1 - link

Myosin va mediates docking of secretory granules at the plasma membrane.
Desnos C, Huet S, Fanget I, Chapuis C, Bottiger C, Racine V, Sibarita JB, Henry JP, Darchen F, J Neurosci, 2007 Sep 26 - link