Reorganization of mammalian body wall patterning with cloacal septation
Abstract Septation of the cloaca is a unique mammalian adaptation that required a novel reorganization of the perineum–the caudal portion of the trunk body wall not associated with the hindlimb. Fish, the basal vertebrates, separate ventrolateral body wall musculature of the trunk into two discrete...
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2017-08-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-017-09359-y |
| _version_ | 1818993881559072768 |
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| author | Margaret I. Hall José R. Rodriguez-Sosa Jeffrey H. Plochocki |
| author_facet | Margaret I. Hall José R. Rodriguez-Sosa Jeffrey H. Plochocki |
| author_sort | Margaret I. Hall |
| collection | DOAJ |
| description | Abstract Septation of the cloaca is a unique mammalian adaptation that required a novel reorganization of the perineum–the caudal portion of the trunk body wall not associated with the hindlimb. Fish, the basal vertebrates, separate ventrolateral body wall musculature of the trunk into two discrete layers, while most tetrapods expand this pattern in the thorax and abdomen into four. Mammals, the only vertebrate group to divide the cloaca into urogenital and anorectal portions, exhibit complex muscle morphology in the perineum. Here we describe how perineal morphology in a broad sample of mammals fits into patterning of trunk musculature as an extension of the four-layer ventrolateral muscular patterning of the thorax and abdomen. We show that each perineal muscle layer has a specific function related to structures formed by cloacal septation. From superficial to deep, there is the subcutaneous layer, which regulates orifice closure, the external layer, which supplements both erectile and micturition function, the internal layer, which provides primary micturition and defecation regulation, and the transversus layer, which provides structural support for pelvic organs. We elucidate how the four-layer body wall pattern, restricted to the non-mammal tetrapod thorax and abdomen, is observed in the mammalian perineum to regulate function of unique perineal structures derived from cloacal septation. |
| first_indexed | 2024-12-20T20:49:06Z |
| format | Article |
| id | doaj.art-603d452f52f54257b089545737804dc4 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-20T20:49:06Z |
| publishDate | 2017-08-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-603d452f52f54257b089545737804dc42022-12-21T19:26:58ZengNature PortfolioScientific Reports2045-23222017-08-01711710.1038/s41598-017-09359-yReorganization of mammalian body wall patterning with cloacal septationMargaret I. Hall0José R. Rodriguez-Sosa1Jeffrey H. Plochocki2Department of Anatomy, Arizona College of Osteopathic Medicine, Midwestern UniversityDepartment of Anatomy, Arizona College of Osteopathic Medicine, Midwestern UniversityDepartment of Anatomy, Arizona College of Osteopathic Medicine, Midwestern UniversityAbstract Septation of the cloaca is a unique mammalian adaptation that required a novel reorganization of the perineum–the caudal portion of the trunk body wall not associated with the hindlimb. Fish, the basal vertebrates, separate ventrolateral body wall musculature of the trunk into two discrete layers, while most tetrapods expand this pattern in the thorax and abdomen into four. Mammals, the only vertebrate group to divide the cloaca into urogenital and anorectal portions, exhibit complex muscle morphology in the perineum. Here we describe how perineal morphology in a broad sample of mammals fits into patterning of trunk musculature as an extension of the four-layer ventrolateral muscular patterning of the thorax and abdomen. We show that each perineal muscle layer has a specific function related to structures formed by cloacal septation. From superficial to deep, there is the subcutaneous layer, which regulates orifice closure, the external layer, which supplements both erectile and micturition function, the internal layer, which provides primary micturition and defecation regulation, and the transversus layer, which provides structural support for pelvic organs. We elucidate how the four-layer body wall pattern, restricted to the non-mammal tetrapod thorax and abdomen, is observed in the mammalian perineum to regulate function of unique perineal structures derived from cloacal septation.https://doi.org/10.1038/s41598-017-09359-y |
| spellingShingle | Margaret I. Hall José R. Rodriguez-Sosa Jeffrey H. Plochocki Reorganization of mammalian body wall patterning with cloacal septation Scientific Reports |
| title | Reorganization of mammalian body wall patterning with cloacal septation |
| title_full | Reorganization of mammalian body wall patterning with cloacal septation |
| title_fullStr | Reorganization of mammalian body wall patterning with cloacal septation |
| title_full_unstemmed | Reorganization of mammalian body wall patterning with cloacal septation |
| title_short | Reorganization of mammalian body wall patterning with cloacal septation |
| title_sort | reorganization of mammalian body wall patterning with cloacal septation |
| url | https://doi.org/10.1038/s41598-017-09359-y |
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