Dev127985 123..132
نویسندگان
چکیده
Olfactory sensory axons target well-defined intermediate targets in the zebrafish olfactory bulb called protoglomeruli well before they form odorant receptor-specific glomeruli. A subset of olfactory sensory neurons are labeled by expression of the or111-7:IRES: GAL4 transgene whose axons terminate in the central zone (CZ) protoglomerulus. Previous work has shown that some of these axons misproject to the more dorsal and anterior dorsal zone (DZ) protoglomerulus in the absence of Netrin 1/Dcc signaling. In search of additional cues that guide these axons to the CZ, we found that Semaphorin 3D (Sema3D) is expressed in the anterior bulb and acts as a repellent that pushes them towards the CZ. Further analysis indicates that Sema3D signaling is mediated through Nrp1a, while Nrp2b also promotes CZ targeting but in a Sema3D-independent manner. nrp1a, nrp2b and dcc transcripts are detected in or111-7 transgene-expressing neurons early in development and both Nrp1a and Dcc act cell-autonomously in sensory neurons to promote accurate targeting to the CZ. dcc and nrp1a double mutants have significantly more DZ misprojections than either single mutant, suggesting that the two signaling systems act independently and in parallel to direct a specific subset of sensory axons to their initial protoglomerular target.
منابع مشابه
Permutations Containing and Avoiding 123 and 132 Patterns
received April 5, 1999, revised May 12, 1999, accepted May 19, 1999. We prove that the number of permutations which avoid 132-patterns and have exactly one 123-pattern, equals (n 2)2n 3 , for n 3. We then give a bijection onto the set of permutations which avoid 123-patterns and have exactly one 132-pattern. Finally, we show that the number of permutations which contain exactly one 123-pattern ...
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We find, in the form of a continued fraction, the generating function for the number of (132)-avoiding permutations that have a given number of (123) patterns, and show how to extend this to permutations that have exactly one (132) pattern. We also find some properties of the continued fraction, which is similar to, though more general than, those that were studied by Ramanujan. the electronic ...
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One of the diagnostic hallmarks of the histological lesions associated with celiac disease is the extensive infiltration of the small intestinal epithelium by CD8(+) T cells of unknown Ag specificity. In this study, we report recognition of the gliadin-derived peptide (A-gliadin 123-132) by CD8(+) T lymphocytes from celiac patients. A-gliadin 123-132-specific IFN-gamma production and cytotoxic ...
متن کاملPatterns and Fractions
We find, in the form of a continued fraction, the generating function for the number of (132)avoiding permutations that have a given number of (123) patterns, and show how to extend this to permutations that have exactly one (132) pattern. We find some properties of the continued fraction, which is similar to, though more general than, those that were studied by Ramanujan. the electronic journa...
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A permutation π ∈ Sn is said to avoid a permutation σ ∈ Sk whenever π contains no subsequence with all of the same pairwise comparisons as σ. In 1985 Simion and Schmidt showed that the number of permutations in Sn which avoid 123, 132, and 213 is the Fibonacci number Fn+1. In this paper we generalize this result in two ways. We first show that the number of permutations which avoid 132, 213, an...
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