Abstract
Gap genes are involved in segment determination during early development of the vinegar fly Drosophila melanogaster and other dipteran insects (flies, midges and mosquitoes). They are expressed in overlapping domains along the antero-posterior (A–P) axis of the blastoderm embryo. While gap domains cover the entire length of the A–P axis in Drosophila, there is a region in the blastoderm of the moth midge Clogmia albipunctata, which lacks canonical gap gene expression. Is a non-canonical gap gene functioning in this area? Here, we characterize tarsal-less (tal) in C. albipunctata. The homologue of tal in the flour beetle Tribolium castaneum (called milles-pattes, mlpt) is a bona fide gap gene. We find that Ca-tal is expressed in the region previously reported as lacking gap gene expression. Using RNA interference, we study the interaction of Ca-tal with gap genes. We show that Ca-tal is regulated by gap genes, but only has a very subtle effect on tailless (Ca-tll), while not affecting other gap genes at all. Moreover, cuticle phenotypes of Ca-tal depleted embryos do not show any gap phenotype. We conclude that Ca-tal is expressed and regulated like a gap gene, but does not function as a gap gene in C. albipunctata.
Highlights
The gap gene network provides the first layer of zygotic regulation in the segmentation gene hierarchy of dipteran insects
While gap domains cover the entire length of the A–P axis in Drosophila, there is a region in the blastoderm of the moth midge Clogmia albipunctata, which lacks canonical gap gene expression
We have characterized the homologue of tal/pri/mlpt in the nematoceran moth midge C. albipunctata
Summary
The gap gene network provides the first layer of zygotic regulation in the segmentation gene hierarchy of dipteran insects (flies, midges and mosquitos). In other cyclorrhaphan flies, such as the hoverfly Episyrphus balteatus [2,3] and the scuttle fly Megaselia abdita [4,5,6], gap gene expression and regulation is strongly conserved. It leads to a set of virtually identical expression domains, comprising overlapping regions of blastoderm nuclei/cells, at the onset of gastrulation. Among the nematoceran Diptera, there is little functional evidence on gap gene regulation expression patterns have been described in the malaria mosquito Anopheles gambiae [7]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
