Cysteine proteinases and programmed cell death in tomato

特定细胞和组织的可控自杀或程序性死亡是大多数多细胞生物发育的自然组成部分。在植物中，水传导组织（树木中的“木材”）的形成完全依赖于直接参与水传导的细胞的程序性死亡。这一过程在支持组织的形成、树木树皮的保护以及植物对病原体入侵的反应中也很重要。衰老，导致秋天落叶的过程也是细胞程序性死亡的结果。然而，这个过程在植物中是如何被控制的还不完全清楚。我们正在研究一组特定的酶在不同植物中单独发生的程序化细胞中的作用，以番茄为我们的模型系统。各种蛋白质消化酶在死亡过程的早期和晚期都起着关键作用。了解细胞和植物如何控制酶在何时何地出现，以及它们如何被激活，将使我们对控制植物细胞死亡过程的整个程序有更全面的了解。

The controlled suicide, or programmed death, of particular cells and tissues is a natural part of development in most multicellular organisms. In plants, the formation of the water conducting tissue, the "wood" in trees, is absolutely dependent on the programmed death of the cells that will be directly involved in water conduction. The process is also important in the formation of supportive tissues, the protective bark of trees, and in the response of plants to pathogen invasion. Senescence, the processes leading to leaf fall in autumn is also a consequence of programmed cell death. How the process is controlled in plants, however, is not fully understood. We are investigating the role of a group of particular enzymes involved in separate occurrences of programmed cell in various plants, using tomato as our model system. The various protein digesting enzymes have key roles in both early and late stages of the death process. Understanding of how the cells and the plant control where and when the enzymes appear and how they are activated should allow us to gain a more complete understanding of the entire program controlling the plant cell death process.