On the cover: Three-dimensional reconstructed confocal microscopy of a live rat basophilic leukemia cell that coexpresses a constitutively active Rab5A mutant (green) and the secretory granules marker NPY-mRFP (magenta). Rab5 stimulates secretory granule fusion forming giant secretory granules, part of which appears to be embedded within Rab5A, while others are naked or bridged with Rab5A. Azouz, N. P., N. Zur, A. Efergan, N. Ohbayashi, M. Fukuda, D. Amihai, I. Hammel, M. E. Rothenberg, and R. Sagi-Eisenberg. 2014. Rab5 is a novel regulator of mast cell secretory granules: impact on size, cargo and exocytosis. J. Immunol. 192: 4043–4053.