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Full-Text Articles in Life Sciences
A Regulatory Code For Neurogenic Gene Expression In The Drosophila Embryo, Michele Markstein, Robert Zinzen, Peter Markstein, Ka Ping Yee, Albert Erives, Angela Stathopoulos, Michael Levine
A Regulatory Code For Neurogenic Gene Expression In The Drosophila Embryo, Michele Markstein, Robert Zinzen, Peter Markstein, Ka Ping Yee, Albert Erives, Angela Stathopoulos, Michael Levine
Michele Markstein
Bioinformatics methods have identified enhancers that mediate restricted expression in the Drosophila embryo. However, only a small fraction of the predicted enhancers actually work when tested in vivo. In the present study, co-regulated neurogenic enhancers that are activated by intermediate levels of the Dorsal regulatory gradient are shown to contain several shared sequence motifs. These motifs permitted the identification of new neurogenic enhancers with high precision: five out of seven predicted enhancers direct restricted expression within ventral regions of the neurogenic ectoderm. Mutations in some of the shared motifs disrupt enhancer function, and evidence is presented that the Twist and …
Immunity Regulatory Dnas Share Common Organizational Features In Drosophila, Kate Senger, Grant W. Armstrong, William J. Rowell, Jennifer M. Kwan, Michele Markstein, Michael Levine
Immunity Regulatory Dnas Share Common Organizational Features In Drosophila, Kate Senger, Grant W. Armstrong, William J. Rowell, Jennifer M. Kwan, Michele Markstein, Michael Levine
Michele Markstein
Infection results in the rapid activation of immunity genes in the Drosophila fat body. Two classes of transcription factors have been implicated in this process: the REL-containing proteins, Dorsal, Dif, and Relish, and the GATA factor Serpent. Here we present evidence that REL-GATA synergy plays a pervasive role in the immune response. SELEX assays identified consensus binding sites that permitted the characterization of several immunity regulatory DNAs. The distribution of REL and GATA sites within these DNAs suggests that most or all fat-specific immunity genes contain a common organization of regulatory elements: closely linked REL and GATA binding sites positioned …
Whole-Genome Analysis Of Dorsal-Ventral Patterning In The Drosophila Embryo, Angelike Stathopoulos, Madeleine Van Drenth, Albert Erives, Michele Markstein, Michael Levine
Whole-Genome Analysis Of Dorsal-Ventral Patterning In The Drosophila Embryo, Angelike Stathopoulos, Madeleine Van Drenth, Albert Erives, Michele Markstein, Michael Levine
Michele Markstein
The maternal Dorsal regulatory gradient initiates the differentiation of several tissues in the early Drosophila embryo. Whole-genome microarray assays identified as many as 40 new Dorsal target genes, which encode a broad spectrum of cell signaling proteins and transcription factors. Evidence is presented that a tissue-specific form of the NF-Y transcription complex is essential for the activation of gene expression in the mesoderm. Tissue-specific enhancers were identified for new Dorsal target genes, and bioinformatics methods identified conserved cis-regulatory elements for coordinately regulated genes that respond to similar thresholds of the Dorsal gradient. The new Dorsal target genes and enhancers represent …
Genome-Wide Analysis Of Clustered Dorsal Binding Sites Identifies Putative Target Genes In The Drosophila Embryo, Michele Markstein, Peter Markstein, Vicky Markstein, Michael Levine
Genome-Wide Analysis Of Clustered Dorsal Binding Sites Identifies Putative Target Genes In The Drosophila Embryo, Michele Markstein, Peter Markstein, Vicky Markstein, Michael Levine
Michele Markstein
Metazoan genomes contain vast tracts of cis-regulatory DNA that have been identified typically through tedious functional assays. As a result, it has not been possible to uncover a cis-regulatory code that links primary DNA sequences to gene expression patterns. In an initial effort to determine whether coordinately regulated genes share a common “grammar,” we have examined the distribution of Dorsal recognition sequences in the Drosophila genome. Dorsal is one of the best-characterized sequence-specific transcription factors in Drosophila. The homeobox gene zerknullt (zen) is repressed directly by Dorsal, and this repression is mediated by a 600-bp silencer, the ventral repression element …