Elucidating the role of ROS in mediating self-incompatibility induced PCD

阐明 ROS 在介导自交不亲和性诱导的 PCD 中的作用

• 批准号: BB/T00486X/1
• 负责人: Maurice Bosch
• 金额: $ 67.11万
• 依托单位: Aberystwyth University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FT00486X%2F1
• 关键词: Elucidating; role; ROS; mediating; self

Self-incompatibility (SI) is an important mechanism used by flowering plants to prevent self-fertilization, which would otherwise result in undesirable inbreeding and loss of plant fitness. For this reason, SI has made a significant contribution to the evolutionary success of flowering plants. After pollination, SI utilizes cell-cell recognition to prevent self-fertilization by inhibition of pollen tube growth, which is crucial for the delivery of sperm cells to the egg cell inside the pistil. This involves a highly specific interaction between a pistil-expressed protein and a cognate pollen protein that results in recognition and inhibition of genetically identical or self- (incompatible) pollen, but not cross (compatible) pollen. In Papaver rhoeas (field poppy), the stigma of the pistil secretes a small protein (PrsS) which acts as a signalling "ligand". Upon pollination, PrsS interacts specifically with "self" pollen expressing the SI receptor (PrpS), allowing pollen to distinguish between "self" and "non-self" female partners. This interaction is the critical step in cell-cell recognition and determining acceptance or rejection which triggers a complex signalling network in incompatible pollen and results in pollen tubes being inhibited and "told" to commit suicide: "Programmed Cell Death" (PCD).Reactive oxygen species (ROS) are unstable molecules that easily react with other molecules in the cell. If a cell contains too many of these ROS molecules (often hydrogen peroxide) they can cause damage to proteins and may even cause cell death. Low levels of tip-localized ROS are important for regulating normal tip growth of pollen. However, we have shown that SI triggers a rapid increase of the ROS levels in another part of the pollen tube and that these high levels of ROS trigger changes of the actin cytoskeleton (crucial for a cell's shape and movement) and that this type of ROS increase activates SI-induced PCD.We recently discovered that these high levels of SI-induced ROS cause changes/damage to a range of different pollen proteins that fulfil important functions in pollen tube growth. The effect of high levels of ROS molecules on protein function and cellular processes has been extensively studied in animals, often in relation to diseases, in particular cancers. However, we know very little about the damaging effect that high levels of ROS can have on the function of plant proteins and their associated cellular processes. The Papaver SI system, that we can mimic in the laboratory by growing pollen tubes in dishes with growth medium and adding the PrsS proteins to trigger the SI response, provides a great opportunity to study these aspects in full detail.Using biochemistry, genetics, and microscopy this project will investigate how high levels of ROS, triggered by SI, affect the function of a range of selected proteins and cellular processes. These fundamental studies are likely to generate excitement in the scientific community as they will not only provide important mechanistic insights into the role of ROS in SI-PCD but also more broadly for our understanding of the consequences of ROS induced protein damage in plant cells. On a practical note, understanding the mechanisms involved in SI-PCD can lead to applications useful to plant breeding. Fertility and seed set are critical for crop yield and thus Food Security. The transfer of SI-PCD traits into food crops could potentially help plant breeders develop F1 hybrid seeds, which produce bigger and more productive F1 hybrid plants, more efficiently and economically. Currently, hand-emasculation is used to produce F1 hybrid seeds, which is time-consuming and expensive. Introducing SI-PCD into a crop species allows it to be crossed without any emasculation, as no self-pollen can fertilize these plants. Thus, utilization of knowledge on SI-PCD, with high levels of ROS as an essential component, provides a potential alternative means to breed F1 hybrid crops.

自我兼容（SI）是开花植物用于防止自我施用的重要机制，否则，这将导致不良的近交和植物健身的丧失。因此，SI为开花植物的进化成功做出了重大贡献。授粉后，SI利用细胞细胞的识别来防止通过抑制花粉管生长的抑制，这对于将精子细胞递送至雌蕊内的卵细胞至关重要。这涉及雌蕊表达的蛋白质与同源花粉蛋白之间的高度特异性相互作用，从而导致识别和抑制遗传上相同或自我（不兼容）花粉，但不是交叉（兼容）花粉。在Papaver Rhoeas（罂粟）中，雌蕊的污名分泌了一种小蛋白（PRS），该蛋白（PRS）充当信号“配体”。授粉后，PRS与表达SI受体（PRP）的“自我”花粉特别相互作用，使花粉可以区分“自我”和“非自我”女性伴侣。这种相互作用是细胞细胞识别和确定接受或排斥的关键步骤，这会触发不兼容花粉中复杂的信号网络，并导致花粉管被抑制并“告诉“自杀自杀”：“程序性细胞死亡”（PCD）。反应性氧气（ROS）物种（ROS）与其他分子无反应的分子，可与其他分子反应。如果细胞包含太多的ROS分子（通常是过氧化氢），它们会对蛋白质造成损害，甚至可能导致细胞死亡。低水平的尖端定位ROS对于调节花粉的正常尖端生长很重要。 However, we have shown that SI triggers a rapid increase of the ROS levels in another part of the pollen tube and that these high levels of ROS trigger changes of the actin cytoskeleton (crucial for a cell's shape and movement) and that this type of ROS increase activates SI-induced PCD.We recently discovered that these high levels of SI-induced ROS cause changes/damage to a range of different pollen proteins that fulfil important functions in pollen tube growth.高水平的ROS分子对蛋白质功能和细胞过程的影响已在动物中进行了广泛的研究，通常与疾病有关。但是，我们对高水平ROS可以对植物蛋白及其相关细胞过程功能具有的破坏作用了解甚少。 The Papaver SI system, that we can mimic in the laboratory by growing pollen tubes in dishes with growth medium and adding the PrsS proteins to trigger the SI response, provides a great opportunity to study these aspects in full detail.Using biochemistry, genetics, and microscopy this project will investigate how high levels of ROS, triggered by SI, affect the function of a range of selected proteins and cellular processes.这些基本研究可能会在科学界引起兴奋，因为它们不仅会为ROS在Si-PCD中的作用提供重要的机械洞察力，而且更广泛地是为了我们理解ROS诱导蛋白质损害植物细胞的后果。实际上，了解SI-PCD所涉及的机制可能会导致对植物育种有用的应用。生育和种子套对于作物产量至关重要，因此至关重要。 Si-PCD特征转移到粮食作物中可能有可能帮助植物育种者开发F1杂种种子，从而更有效，更经济地产生更大，更有生产力的F1杂种植物。目前，手动肢体用于生产F1混合种子，这既耗时又昂贵。将Si-PCD引入农作物物种可以使其在没有任何模拟的情况下进行跨越，因为没有自花胶可以施肥这些植物。因此，具有高水平ROS作为必不可少的成分的SI-PCD知识的利用提供了繁殖F1杂种作物的潜在替代方法。

项目成果

Systems and breakdown of self-incompatibility

• DOI: 10.1080/07352689.2022.2093085
• 发表时间: 2022-07-18
• 期刊: CRITICAL REVIEWS IN PLANT SCIENCES
• 影响因子: 6.9
• 作者: Ahmad, Muhammad Husnain;Rao, Muhammad Junaid;Chai, Lijun
• 通讯作者: Chai, Lijun

Depletion plays a pivotal role in self-incompatibility, revealing a link between cellular energy status, cytosolic acidification and actin remodelling in pollen tubes.

• DOI: 10.1111/nph.18350
• 发表时间: 2022-12
• 期刊: NEW PHYTOLOGIST
• 影响因子: 9.4
• 作者: Wang, Ludi;Lin, Zongcheng;Carli, Jose;Gladala-Kostarz, Agnieszka;Davies, Julia M.;Franklin-Tong, Vernonica E.;Bosch, Maurice
• 通讯作者: Bosch, Maurice

Self-incompatibility requires GPI anchor remodeling by the poppy PGAP1 ortholog HLD1.

• DOI: 10.1016/j.cub.2022.02.072
• 发表时间: 2022-05-09
• 期刊: Current biology : CB
• 作者: Lin Z;Xie F;Triviño M;Zhao T;Coppens F;Sterck L;Bosch M;Franklin-Tong VE;Nowack MK
• 通讯作者: Nowack MK