The multiple roles of caudal in early development of the milkweed bug Oncopeltus fasciatus.

The homeobox transcription factor Caudal has conserved roles in all Bilateria in defining the posterior pole and in controlling posterior elongation. These roles are seemingly similar and are difficult to disentangle. We have carried out a detailed analysis of the expression, function and interactions of the caudal ortholog of the milkweed bug, Oncopeltus fasciatus, a hemimetabolous insect with a conservative early development process, in order to understand its different functions throughout development.

The mlpt/Ubr3/Svb module comprises an ancient developmental switch for embryonic patterning.

Unlabelled: Small open reading frames (smORFs) encoding 'micropeptides' exhibit remarkable evolutionary complexity. Conserved peptides encoded by are essential for embryo segmentation in but, in , function in terminal epidermal differentiation and patterning of adult legs. Here, we show that a molecular complex identified in epidermal differentiation, comprising Mlpt peptides, ubiquitin-ligase Ubr3 and transcription factor Shavenbaby (Svb), represents an ancient developmental module required for early insect embryo patterning.

Growth zone segmentation in the milkweed bug Oncopeltus fasciatus sheds light on the evolution of insect segmentation.

Background: One of the best studied developmental processes is the Drosophila segmentation cascade. However, this cascade is generally considered to be highly derived and unusual, with segments being patterned simultaneously, rather than the ancestral sequential segmentation mode. We present a detailed analysis of the segmentation cascade of the milkweed bug Oncopletus fasciatus, an insect with a more primitive segmentation mode, as a comparison to Drosophila, with the aim of reconstructing the evolution of insect segmentation modes.

The Evolution of Gene Regulatory Networks that Define Arthropod Body Plans.

Our understanding of the genetics of arthropod body plan development originally stems from work on Drosophila melanogaster from the late 1970s and onward. In Drosophila, there is a relatively detailed model for the network of gene interactions that proceeds in a sequential-hierarchical fashion to define the main features of the body plan. Over the years, we have a growing understanding of the networks involved in defining the body plan in an increasing number of arthropod species.

Dynamics of growth zone patterning in the milkweed bug .

We describe the dynamic process of abdominal segment generation in the milkweed bug We present detailed morphological measurements of the growing germband throughout segmentation. Our data are complemented by cell division profiles and expression patterns of key genes, including and as markers for different stages of segment formation. We describe morphological and mechanistic changes in the growth zone and in nascent segments during the generation of individual segments and throughout segmentation, and examine the relative contribution of newly formed versus existing tissue to segment formation.