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Title: Distinct parasegmental and imaginal enhancers and the establishment of the expression pattern of the Ubx gene

Abstract

The expression domain of the Ubx gene in Drosophila embryos is bounded by the product of the hb gene, acting as a repressor. We show that all Ubx fragments that bind Hb protein in vitro contain parasegmental enhancers active in the embryo in specific parasegmental patterns. We have found three new embryonic enhancer elements in the upstream region, in addition to the two previously identified. Each produces a pattern initially bounded at PS6 by Hb but sooner or later breaks down this boundary and begins to express in the anterior region. These enhancers do not respond to the long-term maintenance mediated by the Polycomb group of genes. They also cease functioning after germ band extension. Expression in imaginal tissues is due to a set of entirely separate and independent imaginal disc enhancers. These do not contain Hb binding sites and by themselves have no anterior/posterior positional information, although some distinguish between ventral and dorsal discs. A third kind of element, the Polycomb Response Element (PRE), has no enhancer activity but causes long-term maintenance of the expression domain of other enhancers present in the vicinity. The interaction of these elements results in the correct expression of Ubx in imaginal tissues. 40more » refs., 7 figs.« less

Authors:
; ; ;  [1]
  1. Univ. of Geneva (Switzerland)
Publication Date:
OSTI Identifier:
535346
Resource Type:
Journal Article
Resource Relation:
Journal Name: Genetics; Journal Volume: 141; Journal Issue: 4; Other Information: PBD: Dec 1995
Country of Publication:
United States
Language:
English
Subject:
55 BIOLOGY AND MEDICINE, BASIC STUDIES; DROSOPHILA; EMBRYOS; GENES; GENE REGULATION; GENE REPRESSORS; TRANSCRIPTION; DNA SEQUENCING; STRUCTURE-ACTIVITY RELATIONSHIPS; GENETIC MAPPING; TISSUE DISTRIBUTION; TRANSPOSONS

Citation Formats

Pirrotta, V., Chan, Chi Shing, McCabe, D., and Qian, Su. Distinct parasegmental and imaginal enhancers and the establishment of the expression pattern of the Ubx gene. United States: N. p., 1995. Web.
Pirrotta, V., Chan, Chi Shing, McCabe, D., & Qian, Su. Distinct parasegmental and imaginal enhancers and the establishment of the expression pattern of the Ubx gene. United States.
Pirrotta, V., Chan, Chi Shing, McCabe, D., and Qian, Su. 1995. "Distinct parasegmental and imaginal enhancers and the establishment of the expression pattern of the Ubx gene". United States. doi:.
@article{osti_535346,
title = {Distinct parasegmental and imaginal enhancers and the establishment of the expression pattern of the Ubx gene},
author = {Pirrotta, V. and Chan, Chi Shing and McCabe, D. and Qian, Su},
abstractNote = {The expression domain of the Ubx gene in Drosophila embryos is bounded by the product of the hb gene, acting as a repressor. We show that all Ubx fragments that bind Hb protein in vitro contain parasegmental enhancers active in the embryo in specific parasegmental patterns. We have found three new embryonic enhancer elements in the upstream region, in addition to the two previously identified. Each produces a pattern initially bounded at PS6 by Hb but sooner or later breaks down this boundary and begins to express in the anterior region. These enhancers do not respond to the long-term maintenance mediated by the Polycomb group of genes. They also cease functioning after germ band extension. Expression in imaginal tissues is due to a set of entirely separate and independent imaginal disc enhancers. These do not contain Hb binding sites and by themselves have no anterior/posterior positional information, although some distinguish between ventral and dorsal discs. A third kind of element, the Polycomb Response Element (PRE), has no enhancer activity but causes long-term maintenance of the expression domain of other enhancers present in the vicinity. The interaction of these elements results in the correct expression of Ubx in imaginal tissues. 40 refs., 7 figs.},
doi = {},
journal = {Genetics},
number = 4,
volume = 141,
place = {United States},
year = 1995,
month =
}
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