Genetics Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
Institute of Medical Engineering & Science (IMES), Department of Chemistry, and Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
Nat Commun. 2020 Nov 19;11(1):5785. doi: 10.1038/s41467-020-19558-3.
The liver plays a central role in metabolism, protein synthesis and detoxification. It possesses unique regenerative capacity upon injury. While many factors regulating cellular proliferation during liver repair have been identified, the mechanisms by which the injured liver maintains vital functions prior to tissue recovery are unknown. Here, we identify a new phase of functional compensation following acute liver injury that occurs prior to cellular proliferation. By coupling single-cell RNA-seq with in situ transcriptional analyses in two independent murine liver injury models, we discover adaptive reprogramming to ensure expression of both injury response and core liver function genes dependent on macrophage-derived WNT/β-catenin signaling. Interestingly, transcriptional compensation is most prominent in non-proliferating cells, clearly delineating two temporally distinct phases of liver recovery. Overall, our work describes a mechanism by which the liver maintains essential physiological functions prior to cellular reconstitution and characterizes macrophage-derived WNT signals required for this compensation.
肝脏在新陈代谢、蛋白质合成和解毒中起着核心作用。它在受伤后具有独特的再生能力。虽然已经确定了许多调节肝修复过程中细胞增殖的因素,但对于受伤肝脏在组织恢复之前如何维持重要功能的机制尚不清楚。在这里,我们在两种独立的小鼠肝损伤模型中,通过将单细胞 RNA-seq 与原位转录分析相结合,发现了一个新的肝损伤后功能补偿阶段,该阶段发生在细胞增殖之前。我们发现,适应性重编程可以确保损伤反应和核心肝脏功能基因的表达,这依赖于巨噬细胞衍生的 WNT/β-catenin 信号。有趣的是,转录补偿在非增殖细胞中最为明显,这清楚地区分了肝恢复的两个时间上不同的阶段。总的来说,我们的工作描述了一种肝脏在细胞重建之前维持基本生理功能的机制,并描述了这种补偿所需的巨噬细胞衍生的 WNT 信号。