Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, 420 Delaware Street SE, Minneapolis, MN, 55455, USA.
Division of Molecular Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, USA.
Sci Rep. 2023 May 6;13(1):7387. doi: 10.1038/s41598-023-34435-x.
Cytotrophoblasts fuse to form and renew syncytiotrophoblasts necessary to maintain placental health throughout gestation. During cytotrophoblast to syncytiotrophoblast differentiation, cells undergo regulated metabolic and transcriptional reprogramming. Mitochondria play a critical role in differentiation events in cellular systems, thus we hypothesized that mitochondrial metabolism played a central role in trophoblast differentiation. In this work, we employed static and stable isotope tracing untargeted metabolomics methods along with gene expression and histone acetylation studies in an established BeWo cell culture model of trophoblast differentiation. Differentiation was associated with increased abundance of the TCA cycle intermediates citrate and α-ketoglutarate. Citrate was preferentially exported from mitochondria in the undifferentiated state but was retained to a larger extent within mitochondria upon differentiation. Correspondingly, differentiation was associated with decreased expression of the mitochondrial citrate transporter (CIC). CRISPR/Cas9 disruption of the mitochondrial citrate carrier showed that CIC is required for biochemical differentiation of trophoblasts. Loss of CIC resulted in broad alterations in gene expression and histone acetylation. These gene expression changes were partially rescued through acetate supplementation. Taken together, these results highlight a central role for mitochondrial citrate metabolism in orchestrating histone acetylation and gene expression during trophoblast differentiation.
滋养细胞融合形成并更新合胞滋养层，这对于维持整个妊娠期胎盘的健康是必要的。在滋养细胞向合胞滋养层分化的过程中，细胞经历了受调控的代谢和转录重编程。线粒体在细胞系统的分化事件中起着至关重要的作用，因此我们假设线粒体代谢在滋养细胞分化中起着核心作用。在这项工作中，我们在已建立的 BeWo 滋养细胞分化培养模型中，采用静态和稳定同位素示踪非靶向代谢组学方法以及基因表达和组蛋白乙酰化研究，研究了线粒体代谢在滋养细胞分化中的作用。分化与三羧酸 (TCA) 循环中间产物柠檬酸和α-酮戊二酸的丰度增加有关。在未分化状态下，柠檬酸优先从线粒体中输出，但在分化时更多地保留在线粒体中。相应地，分化与线粒体柠檬酸转运蛋白 (CIC) 的表达下调有关。使用 CRISPR/Cas9 敲除线粒体柠檬酸载体表明，CIC 是滋养细胞生化分化所必需的。CIC 的缺失导致广泛的基因表达和组蛋白乙酰化改变。通过补充乙酸盐，这些基因表达的变化部分得到了挽救。总之，这些结果突出了线粒体柠檬酸代谢在协调滋养细胞分化过程中的组蛋白乙酰化和基因表达方面的核心作用。
