Fig. 4: The piwi1mOr2/P2A-GFP reporter line suggests that the Vasa2+/Piwi1+ stem/progenitor cell population generates germ cells and putative somatic progeny.
From: A population of Vasa2 and Piwi1 expressing cells generates germ cells and neurons in a sea anemone
A–D’ Confocal images of whole-mount, double transgenic piwi1mOr2/P2A-GFP juvenile polyps immunostained for mOr2 (A–D; yellow) and GFP (A, B’, C, D’; cyan). As in adults, high levels of both reporter proteins were detected in basiepithelial cells along the reticular tract (‘rt’) of juvenile mesenteries (A-B’). Cells with [GFP]low/[mOr2-Piwi1]low localize along the parietal muscle and gastrodermal body wall of juveniles (C-D’). Cells with [GFP]high/[mOr2-Piwi1]low (A-B’; black double arrowheads) adjacent to [GFP]high/[mOr2-Piwi1]high cells indicates that unequal cytoplasmic inheritance of fluorophores occurred following a cell division. E–G Schematic 3-dimensional illustration of body column section (E) and cross-sections (F, G) summarizing the ___location and approximate levels of mOr2-Piwi1 and GFP(-P2A-Piwi1) proteins in the juvenile (E, F) and adult (G) mesentery. E Location of mesenterial Vasa2+/Piwi1+ stem/progenitor cells (blue) and their potentially migratory gastrodermal progeny cells (orange). bwg body wall gastrodermis, ep epidermis, m mesentery, n nucleus, o oocyte, pm parietal muscle, rm retractor muscle, rt reticular tract, sg somatic gonad. Scale bars: 10 µm (A–D). All experiments were performed twice with similar results.
