Abstract：
CONCLUSIONS: The preservation of quiescent center stem cell integrity in hypoxic roots by phytoglobins is exercised through their ability to scavenge nitric oxide and attenuate its effects on auxin transport and cell degradation. Under low oxygen stress, the retention or induction of phytoglobin expression maintains cell viability while loss or lack of induction of phytoglobin leads to cell degradation. Plants have evolved unique attributes to ensure survival in the environment in which they must exist. Common among the attributes is the ability to maintain stem cells in a quiescent (or low proliferation) state in unfriendly environments. From the seed embryo to meristematic regions of the plant, quiescent stem cells exist to regenerate the organism when environmental conditions are suitable to allow plant survival. Frequently, plants dispose of mature cells or organs in the process of acclimating to the stresses to ensure survival of meristems, the stem cells of which are capable of regenerating cells and organs that have been sacrificed, a feature not generally available to mammals. Most of the research on plant stress responses has dealt with how mature cells respond because of the difficulty of specifically examining plant meristem responses to stress. This raises the question as to whether quiescent stem cells behave in a similar fashion to mature cells in their response to stress and what factors within these critical cells determine whether they survive or degrade when exposed to environmental stress. This review attempts to examine this question with respect to the quiescent center (QC) stem cells of the root apical meristem. Emphasis is put on how varying levels of nitric oxide, influenced by the expression of phytoglobins, affect QC response to hypoxic stress.
摘要：
结论：通过植物球蛋白清除一氧化氮并减弱其对生长素转运和细胞降解的影响，可以保护低氧根中静止中心干细胞的完整性。在低氧胁迫下，植物球蛋白表达的保留或诱导维持细胞活力,而植物球蛋白诱导的丧失或缺乏导致细胞降解。植物已经进化出独特的属性，以确保在它们必须存在的环境中生存。这些属性中常见的是在不友好的环境中维持干细胞处于静止(或低增殖)状态的能力。从种子胚到植物的分生组织区域，当环境条件适合允许植物存活时,存在静止干细胞以再生生物体。经常,植物在适应压力的过程中处理成熟的细胞或器官，以确保分生组织的存活，其干细胞能够再生已被处死的细胞和器官，哺乳动物通常不具备的功能。由于难以专门检查植物分生组织对胁迫的反应，因此大多数关于植物应激反应的研究都涉及成熟细胞的反应。这提出了一个问题，即静止干细胞在对压力的反应中是否表现出与成熟细胞相似的方式，以及这些关键细胞中的哪些因素决定了它们在暴露于环境压力时是否存活或降解。这篇评论试图针对根尖分生组织的静止中心（QC）干细胞来研究这个问题。重点放在一氧化氮水平的变化，受植体蛋白表达的影响，影响QC对低氧应激的反应。
