当前位置: X-MOL 学术Comp. Biochem. Physiol. B Biochem. Mol. Biol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Physiological processes and lipidome dynamics in the soft coral Sinularia heterospiculata under experimental bleaching
Comparative Biochemistry and Physiology B: Biochemistry & Molecular Biology ( IF 2.2 ) Pub Date : 2021-05-04 , DOI: 10.1016/j.cbpb.2021.110609
Tatyana V Sikorskaya 1 , Ekaterina V Ermolenko 1 , Andrey V Boroda 1 , Taliya T Ginanova 1
Affiliation  

Coral polyps host intracellular symbiotic dinoflagellates (SD). The loss of SD (referred as bleaching) under stressful environmental conditions is the main reason of coral reef destruction, and therefore, intensively studied over the world. Lipids are the structural base of biomembranes and energy reserve of corals and are directly involved in the coral bleaching. In order to establish a relationship between coral tissue morphology, physiological processes and lipidome dynamics during bleaching, the soft coral Sinularia heterospiculata was exposed to experimental heat stress (33 °C) for 72 h. A chlorophyll content, structure of cells, the level of reactive oxygen species (ROS), and molecular species of storage and structural lipids were analyzed. After 24 h of heat exposure, the level of ROS-positive SD cells did not increase, but the host tissues lost a significant part of SD. The removal of SD cells by exocytosis were suggested. Exocytosis was presumed to prevail at earlier stages of the soft coral bleaching. Symbiophagosomes with degenerative SD were observed in the stressed coral host cells. After 24 h, the content of phosphatidylinositols, which involved in apoptosis and autophagy, was significantly decreased. The innate immune response was triggered, and SD were digested by the coral host. After 48 h, a degradation of SD chloroplasts and a decrease in the specific monogalactosyldiacylglycerol molecular species were detected that confirmed a disruption of lipid biosynthesis in chloroplasts. At the end of coral bleaching, the appearance of oxidized phosphatidylethanolamines, indicating damage to the host membranes, and the degradation of the coral tissues were simultaneously observed. Thus, a switch between dominant mechanisms of the SD loss during bleaching of S. heterospiculata was found and proved by certain variations of the lipidomic profile. Lipidomic parameters may become indicators of physiological processes occurring in the symbiotic coral organism and may be used for assessing anthropogenic or natural destructive effects on coral reefs.



中文翻译:

实验漂白下软珊瑚Sinularia heterospiculata的生理过程和脂质组动力学

珊瑚息肉宿主细胞内共生鞭毛藻 (SD)。在压力环境条件下SD的损失(称为漂白)是珊瑚礁破坏的主要原因,因此在世界范围内进行了深入研究。脂质是生物膜的结构基础和珊瑚的能量储备,直接参与珊瑚白化。为了在漂白过程中建立珊瑚组织形态、生理过程和脂质组动力学之间的关系,软珊瑚Sinularia heterospiculata暴露于实验热应力 (33 °C) 72 小时。分析了叶绿素含量、细胞结构、活性氧 (ROS) 水平以及储存和结构脂质的分子种类。热暴露 24 h 后,ROS 阳性 SD 细胞的水平没有增加,但宿主组织失去了很大一部分 SD。建议通过胞吐作用去除 SD 细胞。据推测,在软珊瑚白化的早期阶段,胞吐作用占主导地位。在受压的珊瑚宿主细胞中观察到具有退化 SD 的共生体。24小时后,参与细胞凋亡和自噬的磷脂酰肌醇含量显着降低。先天免疫反应被触发,SD被珊瑚宿主消化。48 小时后,检测到 SD 叶绿体的降解和特定的单半乳糖二酰基甘油分子种类的减少,证实了叶绿体中脂质生物合成的破坏。在珊瑚白化结束时,同时观察到氧化的磷脂酰乙醇胺的出现,表明对宿主膜的破坏和珊瑚组织的降解。因此,漂白过程中 SD 损失的主要机制之间的转换S.heterospiculata被发现并通过脂质组学特征的某些变化得到证实。脂质参数可能成为共生珊瑚生物体中发生的生理过程的指标,并可用于评估对珊瑚礁的人为或自然破坏性影响。

更新日期:2021-05-08
down
wechat
bug