ca puccino, a Droso hila maternal P ef ect gene required P or polarity of the egg and embryo, is related to the vertebrate limb deformity locus Steven Emmons, Huy Phan, John Calley, Wenliang Chen, Brian James, and Lynn ~anseau' Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona 85721 USA We report the molecular isolation of cappuccino (capu), a gene required for localization of molecular determinants within the developing Drosophila oocyte. The carboxy-terminal half of the capu protein is closely related to that of the vertebrate limb defo-ty locus, which is known to function in polarity determination in the developing vertebrate limb. In addition, capu shares both a proline-rich region and a 70-amino-acid domain with a number of other genes, two of which also function in pattern formation, the Saccharomyes cerevisiae BNIl gene and the Aspergillus FigA gene. We also show that capu mutant oocytes have abnormal microtubule distributions and premature microtubule-based cytoplasmic streaming within the oocyte, but that neither the speed nor the timing of the cytoplasmic streaming correlates with the strength of the mutant allele. This suggests that the premature cytoplasmic streaming in capu mutant oocytes does not suffice to explain the patterning defects. By inducing cytoplasmic streaming in wild-type oocytes during mid-oogenesis, we show that premature cytoplasmic streaming can displace staufen protein from the posterior pole, but not gurken mRNA from around the oocyte nucleus.[Key Words: Drosophila; cappuccino; pattern formation; cytoplasmic streaming; maternal effect; oogenesis; f ormins] Received July 5, 1995; revised version accepted August 25, 1995. The developing Drosophila oocyte is an excellent model system for studying the establishment of polarity within a single cell because the embryonic anterior-posterior and dorsal-ventral axes are initially organized within the oocyte. Anterior-posterior axis formation of the larva involves three pathways within the oocyte: one that establishes the anterior end, one at the posterior end to establish the abdomen and pole cells, and one at both termini of the oocyte to establish the ends (for reviews, see Manseau andSchupbach 1989a andNusslein-Volhard et al. 1987). The larval anterior is established during oogenesis through localization of the bicoid mRNA to the anterior end of the oocyte (Berleth et al. 1988; Driever and Niisslein-Volhard 1988a,b). Formation of the abdomen and pole cells requires localization of a large number of molecular determinants to the posterior pole of the developing oocyte (vasa protein, Hay et al. 1988;Lasko and Ashburner 1990; oskar mRNA and protein, Ephrusso et al. 1991;Kim-Ha et al. 1991;Smith et al. 1992; staufen protein, St. Johnston et al. 1991; tudor protein, Bardsley et al. 1993, nanos mRNA and protein, Wang and Lehmann 199 1 ; Ephrussi and Lehmann 1992j 'Corresponding author. Smith et al. 1992; germ cell-less mRNA, Jongens et al. 1994). The termini of the larva are marked during oogenesis b...
SUMMARYBackground: Therapeutic trials with high-dose lansoprazole and omeprazole have been shown to be sensitive clinical tools for diagnosing patients with gastro-oesophageal reflux disease-related non-cardiac chest pain. Aim: To determine the clinical value of a therapeutic trial of high-dose rabeprazole over 7 days in detecting patients with gastro-oesophageal reflux disease-related non-cardiac chest pain. Methods: Double-blind, randomized, placebo-controlled, crossover study. Patients referred by a cardiologist after a comprehensive cardiac work-up were enrolled into the study. Oesophageal mucosal disease was determined by upper endoscopy and 24-h oesophageal pH monitoring assessed acid exposure. Patients were then randomized to either placebo or rabeprazole 20 mg am and 20 mg pm for 7 days. After a washout period of 1 week, patients crossed over to the other arm of the study for an additional 7 days. Patients completed a daily diary
Spire is a maternal effect locus that affects both the dorsal-ventral and anterior-posterior axes of the Drosophila egg and embryo. It is required for localization of determinants within the developing oocyte to the posterior pole and to the dorsal anterior corner. During mid-oogenesis, spire mutants display premature microtubule-dependent cytoplasmic streaming, a phenotype that can be mimicked by pharmacological disruption of the actin cytoskeleton with cytochalasin D. Spire has been cloned by transposon tagging and is related to posterior end mark-5, a gene from sea squirts that encodes a posteriorly localized mRNA. Spire mRNA is not, however, localized to the posterior pole. SPIRE also contains two domains with similarity to the actin monomer-binding WH2 domain, and we demonstrate that SPIRE binds to actin in the interaction trap system and in vitro. In addition, SPIRE interacts with the rho family GTPases RHOA, RAC1 and CDC42 in the interaction trap system. Thus, our evidence supports the model that SPIRE links rho family signaling to the actin cytoskeleton.
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