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

Journal Article · Fri Dec 01 04:00:00 EST 1995 · Genetics

OSTI ID:535346

Pirrotta, V; Chan, Chi Shing; McCabe, D; Qian, Su ^[1]

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1. Univ. of Geneva (Switzerland)

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.

• OSTI ID: 535346
• Journal Information: Genetics, Journal Name: Genetics Journal Issue: 4 Vol. 141; ISSN GENTAE; ISSN 0016-6731
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
DNA SEQUENCING
DROSOPHILA
EMBRYOS
GENE REGULATION
GENE REPRESSORS
GENES
GENETIC MAPPING
STRUCTURE-ACTIVITY RELATIONSHIPS
TISSUE DISTRIBUTION
TRANSCRIPTION
TRANSPOSONS