羽脊内胚胎和再生生发层细胞:对羽毛发育、进化和多样化的启示。

L Alibardi
{"title":"羽脊内胚胎和再生生发层细胞:对羽毛发育、进化和多样化的启示。","authors":"L Alibardi","doi":"","DOIUrl":null,"url":null,"abstract":"<p><p>The formation of feathers occurs by the transformation of the embryonic epidermis of feather filaments into keratinized barbules and barbs. The present ultrastructural study directly documents this transformation in chick and zebrafinch downfeathers and juvenile feathers. The transformation of the epidermis in the feather filament (downfeathers) or in the follicle (juvenile feathers) is similar. The change in cell shape of subperiderm or subsheath cells and surrounding barb vane ridge cells derives from the re-organization of the linear embryonic epithelium into barb ridges. In the latter the stratification of the outer and inner periderm, of the subperiderm/subsheath, and of the germinal layer of the embryonic epidermis is altered. While the external layers produce the sheath and barb vane ridge cells, subperiderm/subsheath cells are displaced into barbule plates that converge medially in the ramus area of the barb ridge. Cells in the barbule plates elongate into barbule and barb cortical cells by the synthesis of longitudinally oriented feather keratin bundles. In the mid-central area of the barb ridge (the ramus area) cells become polygonal and pile up. The external cells accumulate numerous keratin filaments forming cortical cells and are in contact with barbule cells. The above process also occurs in barb ridges of juvenile feathers and of adult feathers before molting. However, barb ridges produced within follicles of juveniles and adult feathers are longer than in downfeathers, and possess long rami. The incorporation of tritiated histidine in barbule and barb cortical cells has been studied by ultrastructural autoradiography. Most of the labeling is cytoplasmic or is associated with bundles of keratin but is not concentrated over keratin. This indicates that together with keratin possible histidine-rich keratin-associated proteins are produced during the elongation from subperiderm/subsheath to barbule/barb cells. Barb cortical cells merge with medullary cells of the ramus area. The latter accumulate lipids and few keratin bundles before degenerating into empty cells. Separation between barbule and barb cortical cells derives from the degeneration of barb vane ridge cells while separation between barb ridges derives from degeneration of cylindrical cells of marginal plates. These supportive cells incorporate less tritiated histidine than barbule/barb cells and their periderm granules are unlabelled with tritiated histidine. This indicates both that supportive cells are metabolically less active than feather-producing cells, and that putative histidine-rich proteins are only present in cells synthesizing feather keratin. Based on the morphogenesis of barb ridges a hypothesis on the evolution of downfeathers and pennaceous feathers is presented. From conical scales, thin hairy-like filaments were produced in which barb ridges were formed. The evolution of barb ridge morphogenesis with no fusion among barb ridges initially produced naked or branched barb-feathers (plumulaceous). After the formation of a follicle, the modulation of barb ridges patterning and their fusion into the rachis produced all the phenotypes of pennaceous feathers, including those later selected for flight.</p>","PeriodicalId":17136,"journal":{"name":"Journal of submicroscopic cytology and pathology","volume":"38 1","pages":"51-76"},"PeriodicalIF":0.0000,"publicationDate":"2006-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Cells of embryonic and regenerating germinal layers within barb ridges: implication for the development, evolution and diversification of feathers.\",\"authors\":\"L Alibardi\",\"doi\":\"\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>The formation of feathers occurs by the transformation of the embryonic epidermis of feather filaments into keratinized barbules and barbs. The present ultrastructural study directly documents this transformation in chick and zebrafinch downfeathers and juvenile feathers. The transformation of the epidermis in the feather filament (downfeathers) or in the follicle (juvenile feathers) is similar. The change in cell shape of subperiderm or subsheath cells and surrounding barb vane ridge cells derives from the re-organization of the linear embryonic epithelium into barb ridges. In the latter the stratification of the outer and inner periderm, of the subperiderm/subsheath, and of the germinal layer of the embryonic epidermis is altered. While the external layers produce the sheath and barb vane ridge cells, subperiderm/subsheath cells are displaced into barbule plates that converge medially in the ramus area of the barb ridge. Cells in the barbule plates elongate into barbule and barb cortical cells by the synthesis of longitudinally oriented feather keratin bundles. In the mid-central area of the barb ridge (the ramus area) cells become polygonal and pile up. The external cells accumulate numerous keratin filaments forming cortical cells and are in contact with barbule cells. The above process also occurs in barb ridges of juvenile feathers and of adult feathers before molting. However, barb ridges produced within follicles of juveniles and adult feathers are longer than in downfeathers, and possess long rami. The incorporation of tritiated histidine in barbule and barb cortical cells has been studied by ultrastructural autoradiography. Most of the labeling is cytoplasmic or is associated with bundles of keratin but is not concentrated over keratin. This indicates that together with keratin possible histidine-rich keratin-associated proteins are produced during the elongation from subperiderm/subsheath to barbule/barb cells. Barb cortical cells merge with medullary cells of the ramus area. The latter accumulate lipids and few keratin bundles before degenerating into empty cells. Separation between barbule and barb cortical cells derives from the degeneration of barb vane ridge cells while separation between barb ridges derives from degeneration of cylindrical cells of marginal plates. These supportive cells incorporate less tritiated histidine than barbule/barb cells and their periderm granules are unlabelled with tritiated histidine. This indicates both that supportive cells are metabolically less active than feather-producing cells, and that putative histidine-rich proteins are only present in cells synthesizing feather keratin. Based on the morphogenesis of barb ridges a hypothesis on the evolution of downfeathers and pennaceous feathers is presented. From conical scales, thin hairy-like filaments were produced in which barb ridges were formed. The evolution of barb ridge morphogenesis with no fusion among barb ridges initially produced naked or branched barb-feathers (plumulaceous). After the formation of a follicle, the modulation of barb ridges patterning and their fusion into the rachis produced all the phenotypes of pennaceous feathers, including those later selected for flight.</p>\",\"PeriodicalId\":17136,\"journal\":{\"name\":\"Journal of submicroscopic cytology and pathology\",\"volume\":\"38 1\",\"pages\":\"51-76\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2006-04-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of submicroscopic cytology and pathology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of submicroscopic cytology and pathology","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0

摘要

羽毛的形成是由羽毛丝的胚胎表皮转化为角化的小枝和倒刺。目前的超微结构研究直接记录了这种转变在雏鸟和斑马鱼羽绒和幼鸟羽毛中的发生。羽毛细丝(羽绒)或毛囊(幼羽)表皮的转变是相似的。下周或亚鞘细胞和周围的倒刺叶脊细胞的形状变化源于线性胚胎上皮向倒刺脊的重组。在后者中,外周皮和内周皮、下周皮/亚鞘和胚胎表皮生发层的分层发生改变。当外层产生鞘和倒刺叶片脊细胞时,下周/亚鞘细胞被移位成在倒刺脊分支区向内侧汇合的小枝板。小枝板上的细胞通过纵向定向的羽毛角蛋白束的合成而延长为小枝和倒刺皮质细胞。在倒刺脊的中央区(分支区)细胞变成多边形并堆积起来。外部细胞积聚大量角蛋白丝形成皮质细胞,并与小管细胞接触。上述过程也发生在幼羽和成年羽在蜕皮前的倒刺脊上。然而,幼鸟和成年鸟的毛囊内产生的倒刺脊比羽绒长,并且具有较长的支。用超微结构放射自显影技术研究了小枝和倒钩皮层细胞中氚化组氨酸的掺入。大多数标记是细胞质的或与角蛋白束有关,但不集中在角蛋白上。这表明在从周下/亚鞘细胞向小枝/倒刺细胞延伸的过程中,可能会产生富含组氨酸的角蛋白相关蛋白和角蛋白。倒刺皮质细胞与支区的髓质细胞合并。后者在退化为空细胞之前积累脂质和少量角蛋白束。小枝和倒刺皮质细胞的分离是由倒刺叶片脊细胞的退化引起的,而倒刺脊细胞的分离是由边缘板圆柱形细胞的退化引起的。这些支持细胞比小枝/倒钩细胞含有更少的氚化组氨酸,它们的周皮颗粒未标记氚化组氨酸。这表明支持细胞的代谢活性低于羽毛生成细胞,并且假定的富含组氨酸的蛋白质只存在于合成羽毛角蛋白的细胞中。根据羽脊的形态发生,提出了羽绒和羽羽的演化假说。从圆锥形的鳞片,产生薄的毛状细丝,其中形成倒刺脊。在没有融合的情况下,倒钩脊形态发生的进化最初产生裸露或分枝的倒钩羽(羽状)。在卵泡形成后,倒刺脊模式的调整及其与轴的融合产生了pennaceous羽状羽毛的所有表型,包括后来选择飞行的羽状羽毛。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Cells of embryonic and regenerating germinal layers within barb ridges: implication for the development, evolution and diversification of feathers.

The formation of feathers occurs by the transformation of the embryonic epidermis of feather filaments into keratinized barbules and barbs. The present ultrastructural study directly documents this transformation in chick and zebrafinch downfeathers and juvenile feathers. The transformation of the epidermis in the feather filament (downfeathers) or in the follicle (juvenile feathers) is similar. The change in cell shape of subperiderm or subsheath cells and surrounding barb vane ridge cells derives from the re-organization of the linear embryonic epithelium into barb ridges. In the latter the stratification of the outer and inner periderm, of the subperiderm/subsheath, and of the germinal layer of the embryonic epidermis is altered. While the external layers produce the sheath and barb vane ridge cells, subperiderm/subsheath cells are displaced into barbule plates that converge medially in the ramus area of the barb ridge. Cells in the barbule plates elongate into barbule and barb cortical cells by the synthesis of longitudinally oriented feather keratin bundles. In the mid-central area of the barb ridge (the ramus area) cells become polygonal and pile up. The external cells accumulate numerous keratin filaments forming cortical cells and are in contact with barbule cells. The above process also occurs in barb ridges of juvenile feathers and of adult feathers before molting. However, barb ridges produced within follicles of juveniles and adult feathers are longer than in downfeathers, and possess long rami. The incorporation of tritiated histidine in barbule and barb cortical cells has been studied by ultrastructural autoradiography. Most of the labeling is cytoplasmic or is associated with bundles of keratin but is not concentrated over keratin. This indicates that together with keratin possible histidine-rich keratin-associated proteins are produced during the elongation from subperiderm/subsheath to barbule/barb cells. Barb cortical cells merge with medullary cells of the ramus area. The latter accumulate lipids and few keratin bundles before degenerating into empty cells. Separation between barbule and barb cortical cells derives from the degeneration of barb vane ridge cells while separation between barb ridges derives from degeneration of cylindrical cells of marginal plates. These supportive cells incorporate less tritiated histidine than barbule/barb cells and their periderm granules are unlabelled with tritiated histidine. This indicates both that supportive cells are metabolically less active than feather-producing cells, and that putative histidine-rich proteins are only present in cells synthesizing feather keratin. Based on the morphogenesis of barb ridges a hypothesis on the evolution of downfeathers and pennaceous feathers is presented. From conical scales, thin hairy-like filaments were produced in which barb ridges were formed. The evolution of barb ridge morphogenesis with no fusion among barb ridges initially produced naked or branched barb-feathers (plumulaceous). After the formation of a follicle, the modulation of barb ridges patterning and their fusion into the rachis produced all the phenotypes of pennaceous feathers, including those later selected for flight.

求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信