{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T15:48:27Z","timestamp":1786549707096,"version":"build-2736575974"},"reference-count":91,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,11,21]],"date-time":"2023-11-21T00:00:00Z","timestamp":1700524800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"JSPS KAKENHI","doi-asserted-by":"publisher","award":["JP 22H02502"],"award-info":[{"award-number":["JP 22H02502"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Viviparity is made possible by the placenta, a structure acquired relatively recently in the evolutionary history of eutherian mammals. Compared to oviparity, it increases the survival rate of the fetus, owing to the eutherian placenta. Questions such as \u201cHow was the placenta acquired?\u201d and \u201cWhy is there diversity in placental morphology among mammalian species?\u201d remain largely unsolved. Our present understanding of the molecules regulating placental development remains unclear, owing in no small part to the persistent obscurity surrounding the molecular mechanisms underlying placental acquisition. Numerous genes associated with the development of eutherian placental morphology likely evolved to function at the fetal\u2013maternal interface in conjunction with those participating in embryogenesis. Therefore, identifying these genes, how they were acquired, and how they came to be expressed specifically at the fetal\u2013maternal interface will shed light on some crucial molecular mechanisms underlying placental evolution. Exhaustive studies support the hypothesis that endogenous retroviruses (ERVs) could be evolutional driving forces for trophoblast cell fusion and placental structure in mammalian placentas including those of the bovine species. This review focuses on bovine ERVs (BERVs) and their expression and function in the placenta.<\/jats:p>","DOI":"10.3390\/biom13121680","type":"journal-article","created":{"date-parts":[[2023,11,21]],"date-time":"2023-11-21T01:48:45Z","timestamp":1700531325000},"page":"1680","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Progressive Exaptation of Endogenous Retroviruses in Placental Evolution in Cattle"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-4480-7258","authenticated-orcid":false,"given":"Toshihiro","family":"Sakurai","sequence":"first","affiliation":[{"name":"School of Pharmaceutical Science, Ohu University, 31-1 Misumido, Koriyama 963-8611, Fukushima, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9120-0475","authenticated-orcid":false,"given":"Kazuya","family":"Kusama","sequence":"additional","affiliation":[{"name":"Department of Endocrine Pharmacology, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji 192-0392, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3798-3560","authenticated-orcid":false,"given":"Kazuhiko","family":"Imakawa","sequence":"additional","affiliation":[{"name":"Research Institute of Agriculture, Tokai University, 9-1-1 Toroku, Higashi-Ku, Kumamoto 862-8652, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1146\/annurev.ecolsys.36.102003.152631","article-title":"Life-history evolution in reptiles","volume":"36","author":"Shine","year":"2005","journal-title":"Annu. 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