The amphibian gray crescent region--a site of developmental information?
The amphibian gray crescent region--a site of developmental information?
复制标题
两栖动物灰色新月区——发育信息的场所？
DOI：
10.1016/0012-1606(72)90029-2
复制
发表时间：
1972
影响因子：
2.7
通讯作者：
Jane F. Wacaster
中科院分区：
文献类型：
--
作者：
Philip Grant;Jane F. Wacaster
为了评价灰新月两栖动物的发育意义，用2537 Å紫外线照射了豚鼠受精卵的植物半球。导致头胚或无胚，表明灰新月诱导能力被破坏。我们提出了两个问题：(1)该综合征是由于与灰新月区紫外线病变相互作用导致细胞核改变所致吗？(2)紫外线对灰新月细胞质、皮层、还是两者都有损伤？为了回答第一个问题，我们将辐照后囊胚和原胚不同部位的供核移植到去核卵子中。如果细胞核因与辐照细胞质和/或皮层的相互作用而不可逆转地受损，这种核移植胚胎应该发育异常。然而，数百例此类移植的结果都是阴性的。接受来自辐照供体细胞核的卵子发育良好，也有对照转移，这表明细胞核不会通过与辐照灰新月细胞质和/或皮层的相互作用而发生不可逆的修饰。第二个问题是通过将分离的生发囊泡和卵细胞浆注射到受辐照的囊胚胚泡中来逆转异常综合征。生发囊泡内容物没有得到逆转，但在30%的病例中，注射受精卵的边缘带细胞质完全逆转了紫外线效应。我们得出结论，紫外线破坏了神经诱导所必需的细胞质因子。
To evaluate the developmental significance of the amphibian gray crescent, vegetal hemispheres of fertilized eggs ofRana pipienswere irradiated with UV at 2537 Å. Acephalic or aneural embryos resulted suggesting that gray crescent inductive ability was destroyed. Two questions were asked: (1) Does the syndrome result from nuclei altered by interacting with UV lesions in the gray crescent region? (2) Does UV damage the gray crescent cytoplasm, cortex, or both?To answer the first question, donor nuclei from different regions of irradiated blastulae and gastrulae were transplanted into enucleated eggs. If nuclei are irreversibly damaged by interactions with irradiated cytoplasm and/or cortex, such nuclear transplant embryos should develope abnormally. The results of hundreds of such transplants, however, were negative. Eggs receiving nuclei from irradiated donors developed as well as control transfers, suggesting that nuclei are not modified irreversibly by interactions with irradiated gray crescent cytoplasm and/or cortex.The second question was investigated by injecting isolated germinal vesicles and egg cytoplasm into blastocoeles of irradiated blastulae to reverse the abnormal syndrome. No reversals were obtained with germinal vesicle contents, but injections of marginal zone cytoplasm of fertilized eggs completely reversed the UV effect in 30% of the cases. We conclude that UV destroys a cytoplasmic factor essential to neural induction.