Legué Emilie, Joyner Alexandra L
Memorial Sloan-Kettering Cancer Center, New York, USA.
Methods Enzymol. 2010;477:153-81. doi: 10.1016/S0076-6879(10)77010-5.
Understanding how cells are assembled in three dimensions to generate an organ, or a whole organism, is a pivotal question in developmental biology. Similarly, it is critical to understand how adult stem cells integrate into an existing organ during regeneration or in response to injury. Key to discovering the answers to these questions is being able to study the various behaviors of distinct cell types during development or regeneration. Fate mapping techniques are fundamental to studying cell behaviors such as proliferation, movement, and lineage segregation, as the techniques allow precursor cells to be marked and their descendants followed and characterized over time. The generation of transgenic mice, combined with the use of site-specific recombinases (SSR) in the mouse genome, has provided a means to develop powerful genetic fate mapping approaches. A key advantage of genetic fate mapping is that it allows cells to be genetically marked, and therefore the mark is transmitted to all the descendants of the initially marked cells. By making modifications to the SSRs that render their enzymatic activity inducible, and the development of an assortment of reporter alleles for marking cells, increasingly sophisticated genetic fate mapping studies can be performed. In this chapter, we review the four main genetic fate mapping methods that utilize intrachromosomal recombination to mark cells (cumulative, inducible, clonal, and intersectional) and one interchromosomal method, the tools required to carry out each approach, and the practical considerations that have to be taken into account before embarking on each type of genetic fate mapping study.
了解细胞如何在三维空间中组装以形成一个器官或整个生物体，是发育生物学中的一个关键问题。同样，了解成体干细胞在再生过程中或对损伤作出反应时如何整合到现有的器官中也至关重要。找到这些问题答案的关键在于能够研究不同细胞类型在发育或再生过程中的各种行为。命运图谱技术是研究细胞行为（如增殖、运动和谱系分离）的基础，因为这些技术可以标记前体细胞，并随着时间的推移追踪和表征它们的后代。转基因小鼠的产生，结合在小鼠基因组中使用位点特异性重组酶（SSR），为开发强大的遗传命运图谱方法提供了一种手段。遗传命运图谱的一个关键优势在于它能够对细胞进行基因标记，因此该标记会传递给最初被标记细胞的所有后代。通过对SSR进行修饰使其酶活性可诱导，并开发各种用于标记细胞的报告基因等位基因，可以进行越来越复杂的遗传命运图谱研究。在本章中，我们将回顾利用染色体内重组来标记细胞的四种主要遗传命运图谱方法（累积法、诱导法、克隆法和交叉法）以及一种染色体间方法、进行每种方法所需的工具，以及在开展每种类型的遗传命运图谱研究之前必须考虑的实际因素。
