TY - JOUR T1 - <em>In vivo</em> clonal analysis reveals spatiotemporal regulation of thalamic nucleogenesis JF - bioRxiv DO - 10.1101/238964 SP - 238964 AU - Samuel Z.H. Wong AU - Earl Parker Scott AU - Ella Borgenheimer AU - Madeline Freeman AU - Guo-li Ming AU - Qing-Feng Wu AU - Hongjun Song AU - Yasushi Nakagawa Y1 - 2017/01/01 UR - http://biorxiv.org/content/early/2017/12/25/238964.abstract N2 - The thalamus, a crucial regulator of cortical functions, is composed of many nuclei arranged in a spatially complex pattern. Thalamic neurogenesis occurs over a short period during embryonic development. These features have hampered the effort to understand how regionalization, cell divisions and fate specification are coordinated and produce a wide array of nuclei that exhibit distinct patterns of gene expression and functions. Here, we performed an in vivo clonal analysis to track the divisions of individual progenitor cells and spatial allocation of their progeny in the developing thalamus. Quantitative analysis of clone compositions revealed evidence for sequential generation of distinct sets of thalamic nuclei that are associated with the location of the founder cell. Furthermore, we identified intermediate progenitor cells that produced two to four neurons populating more than one thalamic nuclei, indicating a late specification of nuclear fate. Our study reveals an organizational principle that governs the spatial and temporal progression of cell divisions and fate specification, and provides a framework for studying cellular heterogeneity and connectivity in the thalamus. ER -