Cover photograph (Copyright © 2007, American Society for Microbiology. All Rights Reserved.): Silencing of the albino-1 (al-1) gene (involved in carotenoid biosynthesis) in the filamentous fungus Neurospora crassa by the RNA interference pathway. Neurospora culture was transformed with a truncated al-1 gene and plated on an agar plate. White, yellow, and orange colonies indicate strong, intermediate, and weak/no silencing of the al-1 gene, respectively. (See related article on p. 3995.)