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General Information
D. melanogaster
FlyBase ID
Feature type
Associated gene
Associated Insertion(s)
Carried in Construct
Also Known As
Key Links
Allele class
Nature of the Allele
Allele class
Mutations Mapped to the Genome
Additional Notes
Associated Sequence Data
DNA sequence
Protein sequence
Progenitor genotype
Caused by aberration
Nature of the lesion

Internal deletion (Rowe, EMBO J. 7: 1107--1114). UbxC1 chromosome makes hybrid RNA, 5' exons of the abd-A transcription unit joined to the 3' exons of the Ubx transcription unit.

A deletion with breakpoints in introns of Ubx and abd-A producing a hybrid abd-A-Ubx product (Rowe, EMBO J. 7:1107--1114 , Casanova, EMBO J. 7:1097--1105 ).

Deletion of part of the Ubx and abd-A genes, resulting in a hybrid gene.

Encodes a fusion protein with its amino terminus derived from abd-A and its carboxyl terminus derived from Ubx, giving it weak activity of both genes.

A deletion of parts of the Ubx and abd-A genes, which results in a fusion gene formed by the remaining parts of Ubx and abd-A.

Deletion of approximately 100kb DNA within the Ubx and abd-A regions of the bithorax complex. The proximal breakpoint is within the Ubx transcription unit at -51kb within an intron (coordinates as in FBrf0040194 and FBrf0042053). This deletes the Ubx promoter, the major 5' coding region and one of the two microexons, but leaves the second microexon and the 3', homeobox-containing exon intact. The distal breakpoint is within a 20kb intron of abd-A, 2-2.5kb from the last exon of the 5' cluster. This deletes the 3' cluster of abd-A exons which encode the homeobox and carboxy-terminal regions of the abd-A protein.

Expression Data
Reporter Expression
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Reporter construct used in assay
Human Disease Associations
Disease Ontology (DO) Annotations
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Disease-implicated variant(s)
Phenotypic Data
Phenotypic Class
Phenotype Manifest In
Detailed Description

Double mutants of UbxC1 and exd have an additive phenotype.

Homozygous larvae have transformed abdominal segments; A1 shows a thoracic pattern (which is probably metathoracic but is difficult to discriminate from mesothoracic) as indicated by the denticle size, the presence of ventral pits and fully developed Keilin's organs. A2-A8 show a mixture of thoracic and abdominal pattern elements, with a gradient from A2 (mostly thoracic) to A8 (mostly abdominal). Hemizygous larvae have a more extreme phenotype; A1 and A2 develop a complete thoracic pattern, and A3-A8 have more thoracic features than in homozygotes. Ventral pits and defective Keilin's organs are present down to A7 in both homo- and hemizygous larvae. Heterozygotes have slightly enlarged halteres and differentiate some bristles in the anterior margin, and frequently have a partial transformation of wing territory to haltere and partial transformation of A1 to a more posterior phenotype.

In homozygous embryos A1 is thoracic with Keilin's organs and ventral pits (resembling T2 more closely than T3 - contrasts with the results in FBrf0063361). A2 to A4 show clear abdominal characteristics, with the denticle morphology becoming progressively more like that of the normal A2/A4 type more posteriorly. Ventral pits are present on all abdominal segments from A1 to A7. A2 to A7 are more 'thoracic' in hemizygotes than in homozygotes.

In homozygotes the first and second abdominal segments show thoracic characteristics, and the ventral denticles of the more posterior abdominal segments resemble those of the first abdominal segment.

External Data
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Phenotypic Class
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Additional Comments
Genetic Interactions
Xenogenetic Interactions
Complementation and Rescue Data
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Stocks (0)
Notes on Origin

Ubx provides the carboxyl end of protein and homeobox. The product is now under the control of the Ubx regulatory elements.

Complementation and phenotypic analysis indicates that UbxC1 retains partial Ubx activity. The developmental properties of the UbxC1 appear to be a mixture of those of Ubx and abd-A. UbxC1 is derepressed in esc- embryos.

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Synonyms and Secondary IDs (2)
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    References (11)