Searls R L
J Exp Zool. 1983 Apr;226(1):59-73. doi: 10.1002/jez.1402260109.
The dorsal and ventral myogenic regions were isolated from the right and left wings of donor chick embryos. After removal of the ectoderm, the myogenic regions were grafted into the dorsal myogenic region of the right wing of host embryos in normal or reversed proximal-distal orientation. All grafts were made so that the surface of the graft originally in contact with ectoderm was dorsal. It was expected that myogenic regions grafted into the myogenic region would participate in the normal formation of the host wing. However, after 7 days of further development many of the host wings had developed abnormal cartilages. To investigate the interactions between the tissue of the host and the tissue of the graft and the source of the tissue giving rise to ectopic cartilages, the donor embryos were labeled with tritiated thymidine. The location and shape of the graft were recorded at the time of the operation. The host wings and adjacent body wall were fixed 1, 3, and 4 days after the operation, sectioned, and prepared as autoradiographs. The location of the grafted cells in the host wing was determined by reconstructing the host wing and adjacent body wall. Serial sections and the reconstructions were examined to discover the correlates of abnormal cartilage formation. The following observations were made: 1) Grafts from the dorsal region of the right and left wing in normal orientation participated in the formation of the groove at the base of the wing ventral to the nineteenth somite that produces the extensor surface of the elbow. Grafts from the ventral region of the right and left wing in normal orientation, and all grafts in reversed orientation, did not participate in the formation of the groove. 2) Grafts in normal orientation increased in length on the axis of the humerus and did not increase in width. Grafts in reversed orientation increased in both length and width. Increase in width caused the graft to extend into the proximo-caudal corner of the wing. 3) Wings with grafts from the dorsal regions of the right and left wings in normal orientation were not clearly abnormal 4 days after the operation. When the groove ventral to the nineteenth somite did not form normally, ectopic cartilage differentiated where the groove should have been from grafted cells of the myogenic region. Increase in width of the graft into the proximo-caudal corner of the wing produced an increased mass of graft cells ventral to the nineteenth somite and an increased amount of ectopic cartilage.
从供体鸡胚的右翼和左翼分离出背侧和腹侧生肌区域。去除外胚层后，将生肌区域以正常或近端 - 远端颠倒的方向移植到宿主胚胎右翼的背侧生肌区域。所有移植操作都确保移植块原本与外胚层接触的表面为背侧。预期移植到生肌区域的生肌区域会参与宿主翅膀的正常形成。然而，在进一步发育7天后，许多宿主翅膀出现了异常软骨。为了研究宿主组织与移植组织之间的相互作用以及异位软骨产生的组织来源，用氚标记的胸腺嘧啶核苷对供体胚胎进行标记。在手术时记录移植块的位置和形状。在手术后1天、3天和4天对宿主翅膀和相邻体壁进行固定、切片，并制备成放射自显影片。通过重建宿主翅膀和相邻体壁来确定移植细胞在宿主翅膀中的位置。检查连续切片和重建图像以发现异常软骨形成的相关因素。观察结果如下：1）来自右翼和左翼背侧区域的正常方向的移植块参与了第十九体节腹侧翅膀基部凹槽的形成，该凹槽产生肘部的伸肌表面。来自右翼和左翼腹侧区域的正常方向的移植块以及所有颠倒方向的移植块均未参与凹槽的形成。2）正常方向的移植块在肱骨轴向上长度增加，宽度未增加。颠倒方向的移植块长度和宽度均增加。宽度增加导致移植块延伸到翅膀的近尾角。3）手术后4天，移植了来自右翼和左翼背侧区域的正常方向移植块的翅膀没有明显异常。当第十九体节腹侧的凹槽未正常形成时，异位软骨从生肌区域的移植细胞中分化出来，出现在凹槽应该出现的位置。移植块向翅膀近尾角的宽度增加导致第十九体节腹侧的移植细胞团增加，异位软骨数量也增加。
