Visualizing the metazoan proliferation-quiescence decision in vivo.
Visualizing the metazoan proliferation-quiescence decision in vivo.
复制标题
体内后生动物增殖-静止决定的可视化。
DOI：
10.7554/elife.63265
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发表时间：
2020-12-22
期刊：
影响因子：
7.7
通讯作者：
Matus DQ
中科院分区：
文献类型：
--
作者：
Adikes RC;Kohrman AQ;Martinez MAQ;Palmisano NJ;Smith JJ;Medwig-Kinney TN;Min M;Sallee MD;Ahmed OB;Kim N;Liu S;Morabito RD;Weeks N;Zhao Q;Zhang W;Feldman JL;Barkoulas M;Pani AM;Spencer SL;Martin BL;Matus DQ
细胞增殖和静止在后生动物发育过程中密切协调。在这里，我们采用细胞周期蛋白依赖性激酶（CDK）传感器，通过活细胞成像来解开秀丽隐杆线虫和斑马鱼细胞周期的这些关键事件。 CDK 传感器由荧光标记的 CDK 底物组成，该底物响应 CDK 活性的增加和随之而来的传感器磷酸化，稳定地从细胞核转移到细胞质。我们证明 CDK 传感器可以区分 G1 中的循环细胞和 G0 中的静止细胞，揭示了一个可能的承诺点和其他不变的秀丽隐杆线虫细胞谱系中的神秘随机性。最后，我们根据新生细胞中 CDK 活性的快照得出了线虫未来增殖行为的预测模型。因此，我们引入了一种活细胞成像工具，以促进在广泛的发育背景下细胞周期控制的体内研究。所有生物都是由细胞组成，细胞形成生物体的不同组织、器官和结构。例如，人体被认为由约 37 万亿个细胞组成，并拥有 200 多种细胞类型。为了维持有机体的正常运转，细胞会分裂以产生新细胞并取代已死亡的细胞。细胞分裂是一个由多个步骤组成的严格控制的过程，细胞不断面临着莎士比亚式的困境，决定是继续分裂（也称为细胞增殖）还是停止该过程（称为静止）。这种困难的平衡行为在生命的各个阶段都至关重要，从胚胎发育到成人的组织生长。潜在途径的问题可能导致癌症等疾病。细胞分裂是由称为 CDK 的蛋白质驱动的，它帮助细胞以正确的顺序完成细胞周期。为了更深入地了解这个复杂的过程，科学家开发了用于监控 CDK 的工具。其中一个工具是荧光生物传感器，这是一种可以插入细胞中的分子，可以响应 CDK 活性而发光和移动。可以使用显微镜在每个细胞中研究和测量生物传感器。阿迪克斯、科尔曼、马丁内斯等人。改造和优化了现有的 CDK 生物传感器，以帮助研究两种常见研究生物（线虫秀丽隐杆线虫和斑马鱼）的细胞分裂以及增殖和静止之间的转换。对该生物传感器的分析表明，如果细胞再次分裂，则细胞分裂结束时的 CDK 活性较高，但如果细胞将变得静止，则 CDK 活性较低。这可能表明细胞在增殖和静止之间做出的决定可能比预期更早发生。优化的生物传感器足够灵敏，可以检测这些差异，甚至可以测量影响线虫某个区域增殖的变化，而该区域曾经被认为是不变的。这种生物传感器的开发提供了一种有用的研究工具，可用于其他生物体。许多研究问题都与细胞分裂有关，因此该工具的应用范围很广。
Cell proliferation and quiescence are intimately coordinated during metazoan development. Here, we adapt a cyclin-dependent kinase (CDK) sensor to uncouple these key events of the cell cycle in Caenorhabditis elegans and zebrafish through live-cell imaging. The CDK sensor consists of a fluorescently tagged CDK substrate that steadily translocates from the nucleus to the cytoplasm in response to increasing CDK activity and consequent sensor phosphorylation. We show that the CDK sensor can distinguish cycling cells in G1 from quiescent cells in G0, revealing a possible commitment point and a cryptic stochasticity in an otherwise invariant C. elegans cell lineage. Finally, we derive a predictive model of future proliferation behavior in C. elegans based on a snapshot of CDK activity in newly born cells. Thus, we introduce a live-cell imaging tool to facilitate in vivo studies of cell-cycle control in a wide-range of developmental contexts. All living things are made up of cells that form the different tissues, organs and structures of an organism. The human body, for example, is thought to consist of some 37 trillion cells and harbor over 200 cell types. To maintain a working organism, cells divide to create new cells and replace the ones that have died. Cell division is a tightly controlled process consisting of several steps, and cells continuously face a Shakespearean dilemma of deciding whether to continue dividing (also known as cell proliferation) or to halt the process (known as quiescence). This difficult balancing act is critical during all stages of life, from embryonic development to tissue growth in an adult. Problems in the underlying pathways can result in diseases such as cancer. Cell division is driven by proteins called CDKs, which help cells to complete their cell cycle in the correct sequence. To gain more insight into this complex process, scientists have developed tools for monitoring CDKs. One such tool is a fluorescent biosensor, a molecule that can be inserted into cells that glows and moves in response to CDK activity. The biosensor can be studied and measured in each cell using a microscope. Adikes, Kohrman, Martinez et al. adapted and optimized an existing CDK biosensor to help study cell division and the switch between proliferation and quiescence in two common research organisms, the nematode Caenorhabditis elegans and the zebrafish. Analysis of this biosensor showed that CDK activity at the end of cell division is higher if the cells will divide again but is low if the cells are going to become quiescent. This could suggest that the decision of a cell between proliferation and quiescence may happen earlier than expected. The optimized biosensor is sensitive enough to detect these differences and can even measure variations that influence proliferation in a region on C. elegans that was once thought to be unchanging. The development of this biosensor provides a useful research tool that could be used in other living organisms. Many research questions relate to cell division and so the applications of this tool are wide ranging.