Development of a Boundary in the Brain

在大脑发育过程中，神经细胞被组织成适当连接回路的功能单位。成人大脑的分层或聚类模式的发育机制尚不清楚。许多研究表明，在神经元连接建立之前，细胞间相互作用和细胞外因子（如细胞粘附分子）在组织这些区域方面发挥了重要作用。该项目利用前脑组织的发展，在那里发现了新的分子抗体，以证明嗅觉输入终止的区域边界的形成。实验操作利用成熟的爪蟾蛙发育模型系统。细胞移植、抗体分子探针和基因表达被用来鉴定涉及的分子及其对确定该区域边界的相对贡献。这些结果将为进一步分析边界形成的分子机制提供重要的基础，因此对于理解嗅觉回路的发展对于理解图案形成的生物学具有重要意义。

During development of the brain, nerve cells become organized into functional units for appropriately connected circuits. Patterns of layers or clustering in the adult brain develop by mechanisms still unclear. There is evidence from many studies that cell-cell interactions and extracellular factors such as cell adhesion molecules play a significant role in organizing such regions before the neuronal connections themselves are established. This project exploits the development of forebrain organization, where novel molecular antibodies have been found to demonstrate formation of a boundary of the region where olfactory inputs terminate. Experimental manipulations utilize the well-established developmental model system of the frog Xenopus. Cell grafting, molecular probes for antibodies and gene expression are used to identify the molecules involved and their relative contributions to defining this regional border. Results will provide an important basis to proceed with analyzing the molecular mechanisms of boundary formation, and so will be important beyond understanding the development of olfactory circuits to understanding the biology of pattern formation in general.