{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T19:22:52Z","timestamp":1770146572512,"version":"3.49.0"},"reference-count":158,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,20]],"date-time":"2021-01-20T00:00:00Z","timestamp":1611100800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this review, we consider transformations of axial symmetry in metazoan evolution and development, the genetic basis, and phenotypic expressions of different axial body plans. In addition to the main symmetry types in metazoan body plans, such as rotation (radial symmetry), reflection (mirror and glide reflection symmetry), and translation (metamerism), many biological objects show scale (fractal) symmetry as well as some symmetry-type combinations. Some genetic mechanisms of axial pattern establishment, creating a coordinate system of a metazoan body plan, bilaterian segmentation, and left\u2013right symmetry\/asymmetry, are analysed. Data on the crucial contribution of coupled functions of the Wnt, BMP, Notch, and Hedgehog signaling pathways (all pathways are designated according to the abbreviated or full names of genes or their protein products; for details, see below) and the axial Hox-code in the formation and maintenance of metazoan body plans are necessary for an understanding of the evolutionary diversification and phenotypic expression of various types of axial symmetry. The lost body plans of some extinct Ediacaran and early Cambrian metazoans are also considered in comparison with axial body plans and posterior growth in living animals.<\/jats:p>","DOI":"10.3390\/sym13020160","type":"journal-article","created":{"date-parts":[[2021,1,21]],"date-time":"2021-01-21T02:36:05Z","timestamp":1611196565000},"page":"160","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Symmetry Transformations in Metazoan Evolution and Development"],"prefix":"10.3390","volume":"13","author":[{"given":"Valeria V.","family":"Isaeva","sequence":"first","affiliation":[{"name":"A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Science, 119071 Moscow, Russia"},{"name":"A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, 690041 Vladivostok, Russia"}]},{"given":"Nickolay V.","family":"Kasyanov","sequence":"additional","affiliation":[{"name":"Institute of Theory and History of Architecture and Town Planning, 105264 Moscow, Russia"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,20]]},"reference":[{"key":"ref_1","unstructured":"Beklemishev, V.N. (1964). Principles of Comparative Anatomy of Invertebrates, Nauka. (In Russian)."},{"key":"ref_2","unstructured":"Gerhart, J.C., and Kirschner, M.W. (1997). Cells, Embryos, and Evolution, Blackwell Science."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Minelli, A. (2003). The Development of Animal Form. 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