A new study in this issue of Developmental Cell (Levin et al., 2012) uses comparative transcriptomics and reveals a stage in nematode development that is enriched for developmental patterning genes. The molecular profile of this phylotypic stage shows similarities with those of vertebrates and flies. The findings have important evolutionary implications.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.devcel.2012.05.001 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Department of Cell & Developmental Biology, School of Biological Sciences, University of California San Diego, La Jolla, CA 92093.
A spectacular diversity of forms and features allow species to thrive in different environments, yet some structures remain relatively unchanged. Insect compound eyes are easily recognizable despite dramatic differences in visual abilities across species. It is unknown whether distant insect species use similar or different mechanisms to pattern their eyes or what types of genetic changes produce diversity of form and function.
View Article and Find Full Text PDFNature
November 2024
Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany.
Complex multicellularity has emerged independently across a few eukaryotic lineages and is often associated with the rise of elaborate, tightly coordinated developmental processes. How multicellularity and development are interconnected in evolution is a major question in biology. The hourglass model of embryonic evolution depicts how developmental processes are conserved during evolution, and predicts morphological and molecular divergence in early and late embryogenesis, bridged by a conserved mid-embryonic (phylotypic) period linked to the formation of the basic body plan.
View Article and Find Full Text PDFEvol Dev
May 2024
State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences (Beijing), Beijing Institute of Lifeomics, Beijing, China.
Tardigrades, commonly known as water bears, are enigmatic organisms characterized by their remarkable resilience to extreme environments despite their simple and compact body structure. To date, there is still much to understand about their evolutionary and developmental features contributing to their special body plan and abilities. This research provides preliminary insights on the conserved and specific gene expression patterns during embryonic development of water bears, focusing on the species Hypsibius exemplaris.
View Article and Find Full Text PDFDev Dyn
April 2024
Molecular Life History Laboratory, Department of Genomics and Evolutionary Biology, National Institute of Genetics, Shizuoka, Japan.
Homology in vertebrate body plans is traditionally ascribed to the high-level conservation of regulatory components within the genetic programs governing them, particularly during the "phylotypic stage." However, advancements in embryology and molecular phylogeny have unveiled the dynamic nature of gene repertoires responsible for early development. Notably, the Nodal and Lefty genes, members of the transforming growth factor-beta superfamily producing intercellular signaling molecules and crucial for left-right (L-R) symmetry breaking, exhibit distinctive features within their gene repertoires.
View Article and Find Full Text PDFBrain Behav Evol
May 2024
Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain.
Background: The phylotypic or intermediate stages are thought to be the most evolutionary conserved stages throughout embryonic development. The contrast with divergent early and later stages derived from the concept of the evo-devo hourglass model. Nonetheless, this developmental constraint has been studied as a whole embryo process, not at organ level.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!