The early stages of development of the chick embryo, leading to primitive streak formation (the start of gastrulation), have received renewed attention recently, especially for studies of the mechanisms of large-scale cell movements and those that position the primitive streak in the radial blastodisc. Over the long history of chick embryology, the terminology used to define different regions has been changing, making it difficult to relate studies to each other. To resolve this objectively requires precise definitions of the regions based on anatomical and functional criteria, along with a systematic molecular map that can be compared directly to the functional anatomy. Here, we undertake these tasks. We describe the characteristic cell morphologies (using scanning electron microscopy and immunocytochemistry for cell polarity markers) in different regions and at successive stages. RNAseq was performed for 12 regions of the blastodisc, from which a set of putative regional markers was selected. These were studied in detail by in situ hybridization. Together this provides a comprehensive resource allowing the community to define the regions unambiguously and objectively. In addition to helping with future experimental design and interpretation, this resource will also be useful for evolutionary comparisons between different vertebrate species.

中文翻译：

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前原始条纹鸡胚的分子解剖学。


鸡胚胎发育的早期阶段，导致原条形成（原肠胚形成的开始），最近受到了新的关注，特别是对大规模细胞运动机制和将原条定位在径向的研究。胚盘。在鸡胚胎学的悠久历史中，用于定义不同区域的术语一直在变化，因此很难将研究相互联系起来。为了客观地解决这个问题，需要根据解剖学和功能标准对区域进行精确定义，以及可以直接与功能解剖学进行比较的系统分子图。在这里，我们承担这些任务。我们描述了不同区域和连续阶段的特征细胞形态（使用扫描电子显微镜和细胞极性标记的免疫细胞化学）。对胚盘的 12 个区域进行 RNAseq，从中选择一组假定的区域标记。通过原位杂交对这些进行了详细研究。这共同提供了全面的资源，使社区能够明确、客观地定义区域。除了帮助未来的实验设计和解释之外，该资源还将有助于不同脊椎动物物种之间的进化比较。