Learn More
Two small RNAs regulate the timing of Caenorhabditis elegans development. Transition from the first to the second larval stage fates requires the 22-nucleotide lin-4 RNA, and transition from late larval to adult cell fates requires the 21-nucleotide let-7 RNA. The lin-4 and let-7 RNA genes are not homologous to each other, but are each complementary to(More)
The notochord and dorsal ectoderm induce dorsoventral compartmentalization of the vertebrate neural tube through the differential regulation of genes such as HNF-3beta, Pax3, Pax6 and snail. Here we analyze the expression of HNF-3beta and snail homologues in the ascidian, Ciona intestinalis, a member of the subphylum Urochordata, the earliest branch in the(More)
The dorsal (dl) morphogen gradient initiates the formation of the mesoderm, neuroectoderm, and dorsal ectoderm by setting different limits of regulatory gene expression along the dorsoventral axis of the early Drosophila embryo. In this paper, we show that low affinity dl-binding sites restrict target gene expression to the ventralmost regions (presumptive(More)
The ascidian tadpole represents the most simplified chordate body plan. It contains a notochord composed of just 40 cells, but as in vertebrates Brachyury is essential for notochord differentiation. Here, we show that the misexpression of the Brachyury gene (Ci-Bra) of Ciona intestinalis is sufficient to transform endoderm into notochord. Subtractive(More)
Dorsoventral patterning in Drosophila is initiated by the maternal regulatory factor dorsal (dl), which is a member of the Rel family of transcription factors. dl functions as a transcriptional activator and repressor to establish different territories of gene expression in the precellular embryo. Differential regulation of dl target genes may be essential(More)
Dorsoventral (DV) patterning of the Drosophila embryo is initiated by a broad Dorsal (Dl) nuclear gradient, which is regulated by a conserved signaling pathway that includes the Toll receptor and Pelle kinase. We investigate the consequences of expressing a constitutively activated form of the Toll receptor, Toll(10b), in anterior regions of the early(More)
A new T-box gene, CiVegTR, was isolated in the ascidian Ciona intestinalis. CiVegTR maternal RNAs become localized to the vegetal cytoplasm of fertilized eggs and are incorporated into muscle lineages derived from the B4.1 blastomere. The CiVegTR protein binds to specific sequences within a minimal, 262-bp enhancer that mediates Ci-snail expression in the(More)
Several human DNA sequences were isolated by virtue of homology to a highly conserved region that has been identified in a number of homeotic genes in Drosophila. Structural analysis of the human DNAs indicate that two separate and distinct regions sharing a high degree of homology with the homeo box sequences of Drosophila are separated by only 5 kb in the(More)
The dorsoventral (DV) patterning of the early Drosophila embryo depends on Dorsal, a maternal sequence-specific transcription factor related to mammalian NF-kappaB. Dorsal controls DV patterning through the differential regulation of approximately 50 target genes in a concentration-dependent manner. Whole-genome methods, including ChIP-chip and ChIP-seq(More)
The large genome of herpes simplex virus type of (HSV-1) encodes at least 80 polypeptides, the majority of which have no recognized function. A subgroup of these gene products appears to be nonessential for virus replication in cell culture, but contributes to the complex life cycle of the virus in the host. To identify such functions, a simple insertional(More)