Molecular, Cellular and Integrative Physiology Ph.D. Program, Michigan State University, East Lansing, Michigan, USA.
D.O.-Ph.D. Program, Michigan State University, East Lansing, Michigan, USA.
Cell Reprogram. 2022 Dec;24(6):353-362. doi: 10.1089/cell.2022.0071. Epub 2022 Nov 3.
Somatic cell reprogramming was first developed to create induced pluripotent stem (iPS) cells. Since that time, the highly dynamic and heterogeneous nature of the reprogramming process has come to be appreciated. Remarkably, a distinct type of stem cell, called induced extraembryonic endoderm (iXEN) stem cell, is also formed during reprogramming of mouse somatic cells by ectopic expression of the transcription factors, OCT4, SOX2, KLF4, and MYC (OSKM). The mechanisms leading somatic cells to adopt differing stem cell fates are challenging to resolve given that formation of either stem cell type is slow, stochastic, and rare. For these reasons, fluorescent gene expression reporters have provided an invaluable tool for revealing the path from the somatic state to pluripotency. However, no such reporters have been established for comparable studies of iXEN cell formation. In this study, we examined the expression of multiple fluorescent reporters, including , , and the endodermal genes, and -alone and in combination, during reprogramming. We show that only simultaneous evaluation of and reliably distinguishes iPS and iXEN cell colonies during reprogramming.
体细胞重编程最初是为了产生诱导多能干细胞 (iPS) 而开发的。从那时起，人们开始认识到重编程过程的高度动态和异质性。值得注意的是，在通过异位表达转录因子 OCT4、SOX2、KLF4 和 MYC (OSKM) 对小鼠体细胞进行重编程时，也会形成一种独特的干细胞，称为诱导性胚胎外内胚层 (iXEN) 干细胞。鉴于形成任何一种干细胞类型的速度都很慢、随机且罕见，因此，导致体细胞采用不同干细胞命运的机制难以解决。出于这些原因，荧光基因表达报告基因为揭示从体细胞状态到多能性的途径提供了非常有价值的工具。然而，对于 iXEN 细胞形成的类似研究，尚未建立这样的报告基因。在这项研究中，我们检查了多个荧光报告基因的表达，包括 、 、和内胚层基因 、 和 -单独和组合，在重编程过程中。我们表明，只有同时评估 和 才能在重编程过程中可靠地区分 iPS 和 iXEN 细胞集落。
