Department of Life Sciences, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy.
Department of Biological, Geological and Environmental Sciences, University of Bologna, Via Irnerio 42, 40126 Bologna, Italy.
Int J Mol Sci. 2021 Aug 8;22(16):8535. doi: 10.3390/ijms22168535.
Global warming leads to a progressive rise in environmental temperature. Plants, as sessile organisms, are threatened by these changes; the male gametophyte is extremely sensitive to high temperature and its ability to preserve its physiological status under heat stress is known as acquired thermotolerance. This latter can be achieved by exposing plant to a sub-lethal temperature (priming) or to a progressive increase in temperature. The present research aims to investigate the effects of heat priming on the functioning of tobacco pollen grains. In addition to evaluating basic physiological parameters (e.g., pollen viability, germination and pollen tube length), several aspects related to a correct pollen functioning were considered. Calcium (Ca) level, reactive oxygen species (ROS) and related antioxidant systems were investigated, also to the organization of actin filaments and cytoskeletal protein such as tubulin (including tyrosinated and acetylated isoforms) and actin. We also focused on sucrose synthase (Sus), a key metabolic enzyme and on the content of main soluble sugars, including UDP-glucose. Results here obtained showed that a pre-exposure to sub-lethal temperatures can positively enhance pollen performance by altering its metabolism. This can have a considerable impact, especially from the point of view of breeding strategies aimed at improving crop species.
全球变暖导致环境温度的逐步上升。植物作为固着生物，受到这些变化的威胁；雄性配子体对高温极为敏感，其在热应激下保持生理状态的能力被称为获得性耐热性。后者可以通过将植物暴露于亚致死温度（引发）或温度逐渐升高来实现。本研究旨在研究热引发对烟草花粉粒功能的影响。除了评估基本的生理参数（例如花粉活力、萌发和花粉管长度）外，还考虑了与花粉正确功能相关的几个方面。研究了钙（Ca）水平、活性氧（ROS）和相关抗氧化系统，还研究了肌动蛋白丝和细胞骨架蛋白（包括酪氨酸化和乙酰化同工型）和肌动蛋白的组织。我们还关注蔗糖合酶（Sus），这是一种关键的代谢酶，以及主要可溶性糖的含量，包括 UDP-葡萄糖。这里获得的结果表明，亚致死温度的预先暴露可以通过改变花粉代谢来积极提高花粉性能。这可能会产生相当大的影响，特别是从旨在提高作物品种的育种策略的角度来看。
