Gene expression suggests conserved mechanisms patterning the heads of insects and myriapods

• Published in: Developmental biology 2011-09, Vol.357 (1), p.64-72
• Main Authors: Janssen, Ralf, Budd, Graham E., Damen, Wim G.M.
• Format: Article
• Language: English
• Subjects: Animals; Arthropoda; arthropods; Arthropods - genetics; Arthropods - metabolism; Axis formation; Bicoid; Blastoderm; Blastoderm - metabolism; Body Patterning - genetics; Conserved Sequence; crocodiles; Drosophila melanogaster; Gene expression; Gene Expression Regulation, Developmental; genes; Genes, Insect; head; Head development; Heads; Insect Proteins - genetics; Insecta - genetics; Insecta - metabolism; insects; Myriapoda; Pattern formation; Segmentation
• ISSN: 0012-1606; 1095-564X; 1095-564X
• DOI: 10.1016/j.ydbio.2011.05.670

Segmentation, i.e. the subdivision of the body into serially homologous units, is one of the hallmarks of the arthropods. Arthropod segmentation is best understood in the fly Drosophila melanogaster. But different from the situation in most arthropods in this species all segments are formed from the early blastoderm (so called long-germ developmental mode). In most other arthropods only the anterior segments are formed in a similar way (so called short-germ developmental mode). Posterior segments are added one at a time or in pairs of two from a posterior segment addition zone. The segmentation mechanisms are not universally conserved among arthropods and only little is known about the genetic patterning of the anterior segments. Here we present the expression patterns of the insect head patterning gene orthologs hunchback (hb), orthodenticle (otd), buttonhead-like (btdl), collier (col), cap-n-collar (cnc) and crocodile (croc), and the trunk gap gene Krüppel (Kr) in the myriapod Glomeris marginata. Conserved expression of these genes in insects and a myriapod suggests that the anterior segmentation system may be conserved in at least these two classes of arthropods. This finding implies that the anterior patterning mechanism already existed in the last common ancestor of insects and myriapods. ► We isolated genes involved in anterior patterning in Drosophila from a myriapod. ► We investigated their expression pattern and found that it is conserved. ► Therefore we suggest that anterior patterning in insects and myriapods is conserved. ► Anterior patterning in chelicerates appears to rely partially on different factors.