Previous studies have provided a detailed model for the regulation of even-skipped (eve) stripe 2 expression in the Drosophila embryo. The bicoid (bcd) regulatory gradient triggers the expression of hunchback (hb); these work synergistically to activate the stripe in the anterior half of the embryo, bcd also coordinates the expression of two repressors, giant (gt) and Kruppel (Kr), which define the anterior and posterior borders of the stripe, respectively. Here, we report the findings of extensive cis- and trans- complementation analyses using a series of defective stripe 2 enhancers in transgenic embryos. This study reaches two primary conclusions. First, the strip 2 enhancer is inherently ‘sensitized’ for repression by gt. We propose that gt specifies the sharp anterior stripe border by blocking two tiers of transcriptional synergy, cooperative binding to DNA and cooperative contact of bound activators with the transcription complex. Second, we find that the synergistic activity of hb and bcd is ‘promiscuous’. For example, a maternally expressed Gal4-Sp1 fusion protein can functionally replace hb in the stripe 2 enhancer. This finding challenges previous proposals for dedicated hb and bcd interactions in the segmentation process.
The eve stripe 2 enhancer employs multiple modes of transcriptional synergy
D.N. Arnosti, S. Barolo, M. Levine, S. Small; The eve stripe 2 enhancer employs multiple modes of transcriptional synergy. Development 1 January 1996; 122 (1): 205–214. doi: https://doi.org/10.1242/dev.122.1.205
Download citation file:
Development Journal Meeting 2023
We are delighted to announce that our 2023 Journal Meeting ‘Unconventional and Emerging Experimental Organisms in Cell and Developmental Biology’ will be held from 17-20 September 2023 at Wotton House, Surrey, UK. Find out more and register here.
Call for papers: Metabolic and Nutritional Control of Development and Regeneration
We are welcoming submissions for our next special issue, which will focus on metabolic and nutritional control of development and regeneration. Submission deadline: 15 May 2023.
preLights 5th Birthday webinar
preLights, our preprint highlighting service, is celebrating its 5th birthday this year. To mark the occasion, join us online on 14 March 2023 at 16:00 GMT for a discussion, led by four preLights alumni, on how to identify and navigate the challenges and opportunities while shaping your career as an early-career researcher.
Transitions in development: Daniel Grimes
Daniel Grimes’s lab studies the consequences of ciliary mutations, including left-right patterning defects and scoliosis. We interviewed Daniel to find out more about his career path, his experience of becoming a group leader and the influence of Jurassic Park.
Preprints in Development
As part of our efforts to support the use of preprints and help curate the preprint literature, we are delighted to launch a new article type: ‘In preprints’. These pieces will discuss one or more recent preprints and place them in a broader context.