Krasuska Urszula, Ciacka Katarzyna, Dębska Karolina, Bogatek Renata, Gniazdowska Agnieszka
Department of Plant Physiology, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland.
Department of Plant Physiology, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland.
J Plant Physiol. 2014 Aug 15;171(13):1132-41. doi: 10.1016/j.jplph.2014.04.015. Epub 2014 May 21.
Deep dormancy of apple (Malus domestica Borkh.) embryos can be overcome by short-term pre-treatment with nitric oxide (NO) or hydrogen cyanide (HCN). Dormancy alleviation of embryos modulated by NO or HCN and the first step of germination depend on temporary increased production of reactive oxygen species (ROS). Direct oxidative attack on some amino acid residues or secondary reactions via reactive carbohydrates and lipids can lead to the formation of protein carbonyl derivatives. Protein carbonylation is a widely accepted covalent and irreversible modification resulting in inhibition or alteration of enzyme/protein activities. It also increases the susceptibility of proteins to proteolytic degradation. The aim of this work was to investigate protein carbonylation in germinating apple embryos, the dormancy of which was removed by pre-treatment with NO or HCN donors. It was performed using a quantitative spectrophotometric method, while patterns of carbonylated protein in embryo axes were analyzed by immunochemical techniques. The highest concentration of protein carbonyl groups was observed in dormant embryos. It declined in germinating embryos pre-treated with NO or HCN, suggesting elevated degradation of modified proteins during seedling formation. A decrease in the concentration of carbonylated proteins was accompanied by modification in proteolytic activity in germinating apple embryos. A strict correlation between the level of protein carbonyl groups and cotyledon growth and greening was detected. Moreover, direct in vitro carbonylation of BSA treated with NO or HCN donors was analyzed, showing action of both signaling molecules as protein oxidation agents.
苹果（Malus domestica Borkh.）胚的深度休眠可通过用一氧化氮（NO）或氰化氢（HCN）进行短期预处理来打破。由NO或HCN调节的胚休眠缓解以及萌发的第一步取决于活性氧（ROS）的暂时增加产生。对某些氨基酸残基的直接氧化攻击或通过活性碳水化合物和脂质的二级反应可导致蛋白质羰基衍生物的形成。蛋白质羰基化是一种广泛接受的共价且不可逆的修饰，导致酶/蛋白质活性的抑制或改变。它还增加了蛋白质对蛋白水解降解的敏感性。这项工作的目的是研究经NO或HCN供体预处理打破休眠的萌发苹果胚中的蛋白质羰基化。使用定量分光光度法进行研究，同时通过免疫化学技术分析胚轴中羰基化蛋白质的模式。在休眠胚中观察到蛋白质羰基基团的最高浓度。在用NO或HCN预处理的萌发胚中其浓度下降，表明在幼苗形成过程中修饰蛋白质的降解增加。苹果胚萌发过程中羰基化蛋白质浓度的降低伴随着蛋白水解活性的改变。检测到蛋白质羰基基团水平与子叶生长和变绿之间存在严格的相关性。此外，分析了用NO或HCN供体处理的牛血清白蛋白（BSA）的直接体外羰基化，表明这两种信号分子作为蛋白质氧化剂的作用。
