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Hybridization Screen (hybridization + screen)
Selected AbstractsGenomic profiling of Mixer and Sox17, targets during Xenopus endoderm developmentDEVELOPMENTAL DYNAMICS, Issue 2 2006Kari Dickinson Abstract The transcription factors Mixer and Sox17, have well-characterized roles in endoderm specification during Xenopus embryogenesis. In order to more thoroughly understand the mechanisms by which these endodermal regulators act, we expressed Mixer and Sox17, in naïve ectodermal tissue and, using oligonucleotide-based microarrays, compared their genomic transcriptional profile to that of unaffected tissue. Using this approach, we identified 71 transcripts that are upregulated by Mixer or Sox17,, 63 of which have previously uncharacterized roles in endoderm development. Furthermore, an in situ hybridization screen using antisense probes for several of these clones identified six targets of Mixer and/or Sox17, that are expressed in the endoderm during gastrula stages, providing new and regional markers of the endoderm. Our results contribute further insight into the functions of Mixer and Sox17, and bring us closer to understanding at the molecular level the pathways that regulate endoderm development. Developmental Dynamics 235:368,381, 2006. © 2005 Wiley-Liss, Inc. [source] An automated in situ hybridization screen in the medaka to identify unknown neural genesDEVELOPMENTAL DYNAMICS, Issue 3 2005Carole Deyts Abstract Despite the fact that a large body of factors that play important roles in development are known, there are still large gaps in understanding the genetic pathways that govern these processes. To find previously unknown genes that are expressed during embryonic development, we optimized and performed an automated whole-mount in situ hybridization screen on medaka embryos at the end of somitogenesis. Partial cDNA sequences were compared against public databases and identified according to similarities found to other genes and gene products. Among 321 isolated genes showing specific expression in the central nervous system in at least one of five stages of development, 55.14% represented genes whose functions are already documented (in fish or other model organisms). Additionally, 16.51% were identified as conserved unknown genes or genes with unknown function. We provide new data on eight of these genes that presented a restricted expression pattern that allowed for formulating testable hypotheses on their developmental roles, and that were homologous to mammalian molecules of unknown function. Thus, gene expression screening in medaka is an efficient tool for isolating new regulators of embryonic development, and can complement genome-sequencing projects that are producing a high number of genes without ascribed functions. Developmental Dynamics 234:698,708, 2005. © 2005 Wiley-Liss, Inc. [source] Oosp1 encodes a novel mouse oocyte-secreted proteinGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 3 2001Changning Yan Abstract Summary: Oocyte-somatic cell communication is necessary for normal ovarian function. However, the identities of the majority of oocyte-secreted proteins remain unknown. A novel cDNA encoding mouse oocyte- secreted protein 1 (OOSP1) was identified using a modified subtractive hybridization screen. The Oosp1 cDNA encodes a 202-amino acid protein that contains a 21-amino acid signal peptide sequence, 5 putative N-linked glycosylation consensus sequences, and 6 cysteines that are predicted to form 3 disulfide bonds. OOSP1 shares amino acid identity with placental-specific protein 1 (PLAC1), a secreted protein expressed in the placenta and the ectoplacental cone. The Oosp1 mRNA is approximately 1.0 kb and is present at high levels in the oocytes of adult ovaries and at lower levels in the spleen. The mouse Oosp1 gene is 5 exons, spans greater than 16.4 kb, and localizes to chromosome 19 at a position that shares synteny with human chromosome 11q12,11q13. The identification of OOSP1 as a new oocyte-secreted protein permits future in vitro and in vivo functional analyses to define its role in ovarian folliculogenesis. genesis 31:105,110, 2001. © 2001 Wiley-Liss, Inc. [source] Priming by airborne signals boosts direct and indirect resistance in maizeTHE PLANT JOURNAL, Issue 1 2007Jurriaan Ton Summary Plants counteract attack by herbivorous insects using a variety of inducible defence mechanisms. The production of toxic proteins and metabolites that instantly affect the herbivore's development are examples of direct induced defence. In addition, plants may release mixtures of volatile organic compounds (VOCs) that indirectly protect the plant by attracting natural enemies of the herbivore. Recent studies suggest that these VOCs can also prime nearby plants for enhanced induction of defence upon future insect attack. However, evidence that this defence priming causes reduced vulnerability to insects is sparse. Here we present molecular, chemical and behavioural evidence that VOC-induced priming leads to improved direct and indirect resistance in maize. A differential hybridization screen for inducible genes upon attack by Spodoptera littoralis caterpillars identified 10 defence-related genes that are responsive to wounding, jasmonic acid (JA), or caterpillar regurgitant. Exposure to VOCs from caterpillar-infested plants did not activate these genes directly, but primed a subset of them for earlier and/or stronger induction upon subsequent defence elicitation. This priming for defence-related gene expression correlated with reduced caterpillar feeding and development. Furthermore, exposure to caterpillar-induced VOCs primed for enhanced emissions of aromatic and terpenoid compounds. At the peak of this VOC emission, primed plants were significantly more attractive to parasitic Cotesia marginiventris waSPS. This study shows that VOC-induced priming targets a specific subset of JA-inducible genes, and links these responses at the molecular level to enhanced levels of direct and indirect resistance against insect attack. [source] | ||||||||||