Место издания:KMK Scientific Press Ltd Russian Federation
Первая страница:12
Последняя страница:12
Аннотация:Colonial hydrozoans are animals with one of the most diverse body plans within the Metazoa.
Because of this traits they are felicitous organisms for studying the evolution of metazoan body plans. Canonical Wnt signaling plays a central role in the specification of the main oral-aboral axis of the body during Cnidaria development. However, the question of the involvement of the Wnt pathway in the regulation of the spatial organization of complexly organized colonial organisms is still obscure. Here we used the non-model colonial hydroids Dynamena pumila (Linnaeus, 1758) to study molecular mechanisms of the hydrozoan colony spatial organization. D. pumila has a monopodial colony with terminally located growing tips on the shoots. In this type of branching morphogenesis, during each internode formation, the shoot growing tip is divided into three parts: two lateral hydrants and the central one – which remains a growing tip. Investigation of expression patterns of Wnt/β-catenin signaling components revealed that for growing tip patterning responsible at least three Wnt pathway genes: β-catenin, TCF and Brachyury 2. Functional experiments have shown that prolonged activation of the Wnt signaling during the metamorphosis of the D. pumila inhibit shoot growing tip formation, but not a stolon growing tip. This result in a stolonial colony formation, characteristic for other hydroid species. Our results suggests that the fine-tuning of the Wnt/β-catenin signaling activity level was one of the leading factors in the evolution of the colony spatial organization of the thecate hydroids.
This work is supported by RFBR grant № 17-04-01988a.