English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The Abdominal-B (Abd-B) gene of the Drosophila bithorax complex is a homeotic gene with two subfunctions: the morphogenetic element required for specifying the identity of parasegments (PS) 10-13 and the regulatory element that represses the expression of other homeotic genes in PS14. Here, we provide evidence that four classes of overlapping transcripts are generated from the Abd-B gene and characterize three of the transcripts in detail. We determined the transcription initiation sites for the 4.6- and 3.4-kb RNAs and show that they are generated from separate promoters. Both of these transcripts are present throughout the period during which the Abd-B subfunctions are required. A mutation that inactivates the morphogenetic function is associated with a 411-bp deletion of the initiation site for the 4.6-kb RNA. The regulatory function mutations disrupt the transcription unit for the 3.4-, but not the 4.6-kb, RNA. These results support the assignment of the morphogenetic function to the 4.6-kb RNA and the regulatory function to the 3.4-kb RNA. A 7.8-kb RNA expressed during embryogenesis may also contribute to the regulatory function. Sequence analysis of cDNAs indicates that the 4.6-kb RNA encodes a 55-kD protein (the m protein), whereas the 3.4-kb RNA encodes a 30-kD protein (the r protein). The m and r proteins share a carboxy-terminal sequence that includes the homeo domain, but the r protein lacks a glutamine-rich amino-terminal domain found in the m protein.

The morphogenetic and regulatory functions of the Drosophila Abdominal-B gene are encoded in overlapping RNAs transcribed from separate promoters.