A Drosophila Stat gene (D-Stat) with a zygotic segmental expression pattern was identified. This protein becomes phosphorylated on Tyr-704 when coexpressed in Schneider cells janus kinase (JAK), Hopscotch (HOP). The binds specifically to the consensus sequence TTCCCGGAA. Suppressor mutations of hopTum-l, dominant hyperactive allele hop whose phenotype is hematocyte overproduction and tumor formation, were selected. One these mutantsstatHJ, mapped same chromosomal region (92E) as does D-Stat,...

Gene expression stripes in Drosophila melanogaster embryos provide a model for how eukaryotic promoters are turned on and off response to combinations of transcriptional regulators. Genetic studies suggested that even-skipped ( eve ) stripe 2 is controlled by three gap genes, hunchback hb ), Kruppel Kr giant gt the maternal morphogen bicoid bcd ). A direct link established between binding sites these regulatory proteins promoter element during early embryogenesis. The protein mediate...

Previous studies on the regulation of segmentation geneeven-skipped(eve) have centered transcription stripe 2. Here, we characterize another enhancer module contained within complexevepromoter that directs expression stripes 3 and 7. This is ∼500 bp in length maps ∼3.3 kb upstream start site. The + 7 appears to be regulated by one or more ubiquitously distributed activators, including components a JAK-Stat pathway. two-stripe pattern results via multiple tiers repressors which delimit this...

Previous studies have provided a detailed model for the regulation of even-skipped (eve) stripe 2 expression in Drosophila embryo. The bicoid (bcd) regulatory gradient triggers hunchback (hb); these work synergistically to activate anterior half embryo, bcd also coordinates two repressors, giant (gt) and Kruppel (Kr), which define posterior borders stripe, respectively. Here, we report findings extensive cis- trans- complementation analyses using series defective enhancers transgenic...

The maternal morphogen Bicoid (Bcd) is distributed in an embryonic gradient that critical for patterning the anterior–posterior (AP) body plan Drosophila . Previous work identified several target genes respond directly to Bcd-dependent activation. Positioning of these targets along AP axis thought be controlled by cis-regulatory modules (CRMs) contain clusters Bcd-binding sites different “strengths.” Here we use a combination Bcd-site cluster analysis and evolutionary conservation predict...

In vivo cross-linking studies suggest that the Drosophila transcription factor Bicoid (Bcd) binds to several thousand sites during early embryogenesis, but it is not clear how many of these binding events are functionally important. contrast, reporter gene have identified >60 Bcd-dependent enhancers, all which contain clusters consensus sequence TAATCC. These also TAATCC motifs (inactive fragments) failed drive activation. general, active fragments showed higher levels Bcd in and were...

Neural cell adhesion molecules (NCAMs) are surface glycoproteins that appear to mediate cell-cell adhesion. In vertebrates NCAMs exist in at least three different polypeptide forms of apparent molecular masses 180, 140, and 120 kD. The 180- 140-kD span the plasma membrane whereas 120-kD form lacks a transmembrane region. this study, we report isolation NCAM clones from an adult rat brain cDNA library. Sequence analysis indicated longest isolate, pR18, contains 2,574 nucleotide open reading...

The Bicoid (Bcd) transcription factor is distributed as a long-range concentration gradient along the anterior posterior (AP) axis of Drosophila embryo. Bcd required for activation series target genes, which are expressed at specific positions within gradient. Here we directly tested whether different thresholds establish relative its genes by flattening and systematically varying expression levels. Genome-wide profiles were used to estimate total number general correlation was found between...

Early embryogenesis is characterized by the maternal to zygotic transition (MZT), in which maternally deposited messenger RNAs are degraded while transcription begins. Before MZT, post-transcriptional gene regulation RNA-binding proteins (RBPs) dominant force embryo patterning. We used two mRNA interactome capture methods identify RBPs bound polyadenylated transcripts within first 2 h of Drosophila melanogaster embryogenesis. identified a high-confidence set 476 putative and confirmed...

During development of the rat central nervous system, neural cell adhesion molecule (NCAM) mRNAs containing in extracellular domain a 30-bp alternative exon, here named VASE, replace RNAs that lack this exon. The presence exon between previously described exons 7 and 8 changes predicted loop structure derived polypeptide from one resembling an immunoglobulin constant region to variable domain. This change could have significant effects on NCAM function cell-cell interaction. In report we...

The even-skipped (eve) promoter contains a series of enhancers that control the expression different segmentation stripes in Drosophila embryo. stripe 3 enhancer is located 1.7 kb upstream 2 enhancer. Here we demonstrate these must be physically separated by minimum distance for proper expression. When they are directly coupled either orientation, generate abnormal patterns early For example, levels augmented and there posterior expansion pattern when positioned immediately Despite this...

The long-germ mode of embryogenesis, in which segments arise simultaneously along the anteriorposterior axis, has evolved several times different lineages holometabolous, or fully metamorphosing, insects. Drosophila's fate map is established largely by activity dipteran-specific Bicoid (Bcd) morphogen gradient, operates both instructively and permissively to accomplish anterior patterning. By contrast, all nondipteran insects must achieve patterning independently bcd. We show that bcd's...

The major membrane-associated or transmembrane isoforms of the neural cell adhesion molecule (NCAM) are generated by alternative splicing at 3' end mRNA. Further diversity in NCAM structure is observed extracellular region polypeptide, where insertion additional amino acid residues can result from events occurring exon 7-exon 8 and 12-exon 13 junctions. Here we report characterization tissue-specific patterns junction using polymerase chain reaction. Nine alternatively spliced sequences rat...

Developmental genetic analysis has shown that embryos of the parasitoid wasp Nasonia vitripennis depend more on zygotic gene products to direct axial patterning than do Drosophila embryos. In Drosophila, anterior is largely established by bicoid, a rapidly evolving maternal-effect gene, working with hunchback, which expressed both maternally and zygotically. Here,we focus comparative hunchback function expression. We find lesion in responsible for severe headless mutant phenotype, most head...

The striped expression pattern of the pair-rule gene even skipped(eve) is established by five stripe-specific enhancers, each which responds in a unique way to gradients positional information earlyDrosophila embryo. enhancer for eve stripe 2(eve 2) directly activated morphogens Bicoid (Bcd) and Hunchback (Hb). As these proteins are distributed throughout anterior half embryo, formation single requires that activation prevented all nuclei 2 position. gap genegiant (gt) involved repression...