2006 果蝇背腹模式基因.pdf

Comprehensive identification of Drosophila dorsal–ventral patterning genes using a whole-genome tiling array ´ ´ † † † Frederic Biemar*, David A. Nix , Jessica Piel*, Brant Peterson*, Matthew Ronshaugen*, Victor Sementchenko , Ian Bell , J. Robert Manak†, and Michael S. Levine*‡ *Division of Genetics and Development, Department of Molecular Cell Biology, Center for Integrative Genomics, University of California, Berkeley, CA 94720; and †Affymetrix, Inc., Santa Clara, CA 95951 Contributed by Michael S. Levine, June 5, 2006 Dorsal–ventral (DV) patterning of the Drosophila embryo is initi- of novel exons. And finally, tiling arrays contain nonprotein ated by Dorsal, a sequence-specific transcription factor distributed coding genes such as those that specify miRNAs. Indeed, miR-1, in a broad nuclear gradient in the precellular embryo. Previous a mesoderm-specific miRNA, is directly activated by high levels studies have identified as many as 70 protein-coding genes and of the gradient in the mesoderm where it influences the activities one microRNA (miRNA) gene that are directly or indirectly regu- of genes required for the differentiation of the dorsal vessel, the lated by this gradient. A gene regulation network, or circuit Drosophila heart (3–5). miR-1 expression is regulated by at least diagram, including the functional interconnections among 40 Dor- two distinct tissue-specific enhancers located in distal and prox- sal target genes and 20 associated tissue-specific enhancers, has imal regions of the 5 flanking region, respectively. The distal been determined for the initial stages of gastrulation. Here, we enhancer contains a cluster of linked Dorsa