Cover photograph (Copyright © 2007, American Society for Microbiology. All Rights Reserved.): Hypha of Neurospora crassa expressing a chitin synthase (CHS-6) tagged with green fluorescent protein (GFP) and stained with the endocytic marker FM4-64. From top to bottom: overall appearance in phase-contrast; localization of CHS-6-GFP (in green) at both the core of the Spitzenkörper (round body at the apex) and different compartments in the hyphal tube; staining of the cell surface, Spitzenkörper, and mitochondria with FM4-64 (in red); and a merged image showing GFP and FM4-64 fluorescence. (See related article on page 1853.)