Cover photograph (Copyright © 1999, American Society for Microbiology. All rights reserved.): The human hnRNP K protein negatively regulates the expression of the Drosophila hnRNP K gene bancal. Expression of the human protein was targeted to specific cells in the wing imaginal disks. The disks were double stained with antibodies against the human K protein (red) and the Drosophila Bancal protein (green). Some cells (white arrow) express low levels of both human and Drosophila K protein, suggesting that human K protein represses expression of the bancal gene in a dose-sensitive manner. (See related article on page 7846.)