Characterization of Notch-class gene expression in segmentation stem cells and segment founder cells in Helobdella robusta (Lophotrochozoa; Annelida; Clitellata; Hirudinida; Glossiphoniidae)
| Autor: | Brian J. Norris, Ajna S. Rivera, David A. Weisblat, Mi Hye Song, Foster C. Gonsalves |
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| Rok vydání: | 2005 |
| Předmět: |
Genetics
Regulation of gene expression animal structures food.ingredient Annelid Receptors Notch biology Stem Cells Helobdella Lophotrochozoa Notch signaling pathway Gene Expression Regulation Developmental biology.organism_classification food Evolutionary biology Leeches Helobdella robusta Animals Cell Lineage Segmentation Stem cell Ecology Evolution Behavior and Systematics Body Patterning Signal Transduction Developmental Biology |
| Zdroj: | Evolution Development. 7:588-599 |
| ISSN: | 1525-142X 1520-541X |
| Popis: | To understand the evolution of segmentation, we must compare segmentation in all three major groups of eusegmented animals: vertebrates, arthropods, and annelids. The leech Helobdella robusta is an experimentally tractable annelid representative, which makes segments in anteroposterior progression from a posterior growth zone consisting of 10 identified stem cells. In vertebrates and some arthropods, Notch signaling is required for normal segmentation and functions via regulation of hes-class genes. We have previously characterized the expression of an hes-class gene (Hro-hes) during segmentation in Helobdella, and here, we characterize the expression of an H. robusta notch homolog (Hro-notch) during this process. We find that Hro-notch is transcribed in the segmental founder cells (blast cells) and their stem-cell precursors (teloblasts), as well as in other nonsegmental tissues. The mesodermal and ectodermal lineages show clear differences in the levels of Hro-notch expression. Finally, Hro-notch is shown to be inherited by newly born segmental founder cells as well as transcribed by them before their first cell division. |
| Databáze: | OpenAIRE |
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