Fungal-associated NO is involved in the regulation of oxidative stress during rehydration in lichen symbiosis

BMC Microbiology

Research Article

Myriam Catalá¹  Ana E Pradas del Real¹  Eva Barreno²  Francisco Gasulla²  Jose Reig-Armiñana²  Francisco García-Breijo³ 

[1] Universidad Rey Juan Carlos, Biología Celular, Dpto. Biología y Geología, (ESCET), Madrid, Spain;Universitat de València, Botánica & ICBIBE-Jardí Botànic, Fac. CC. Biológicas, C/Dr. Moliner 50, 46100, Burjassot, Valencia, Spain;Universitat de València, Botánica & ICBIBE-Jardí Botànic, Fac. CC. Biológicas, C/Dr. Moliner 50, 46100, Burjassot, Valencia, Spain;U. Politécnica de Valencia. Dpto. Ecosistemas Agroforestales, Camino de Vera s/n, 46022, Valencia, Spain;

关键词: Reactive Oxygen Species;    Nitric Oxide;    Reactive Oxygen Species Production;    Lichen Species;    Cumene Hydroperoxide;   

DOI  :  10.1186/1471-2180-10-297

 received in 2010-05-28, accepted in 2010-11-22,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundReactive oxygen species (ROS) are normally produced in respiratory and photosynthetic electron chains and their production is enhanced during desiccation/rehydration. Nitric oxide (NO) is a ubiquitous and multifaceted molecule involved in cell signaling and abiotic stress. Lichens are poikilohydrous organisms that can survive continuous cycles of desiccation and rehydration. Although the production of ROS and NO was recently demonstrated during lichen rehydration, the functions of these compounds are unknown. The aim of this study was to analyze the role of NO during rehydration of the lichen Ramalina farinacea (L.) Ach., its isolated photobiont partner Trebouxia sp. and Asterochloris erici (Ahmadjian) Skaloud et Peksa (SAG 32.85 = UTEX 911).ResultsRehydration of R. farinacea caused the release of ROS and NO evidenced by the fluorescent probes DCFH2-DA and DAN respectively. However, a minimum in lipid peroxidation (MDA) was observed 2 h post-rehydration. The inhibition of NO in lichen thalli with c-PTIO resulted in increases in both ROS production and lipid peroxidation, which now peaked at 3 h, together with decreases in chlorophyll autofluorescence and algal photobleaching upon confocal laser incidence. Trebouxia sp. photobionts generate peaks of NO-endproducts in suspension and show high rates of photobleaching and ROS production under NO inhibition which also caused a significant decrease in photosynthetic activity of A. erici axenic cultures, probably due to the higher levels of photo-oxidative stress.ConclusionsMycobiont derived NO has an important role in the regulation of oxidative stress and in the photo-oxidative protection of photobionts in lichen thalli. The results point to the importance of NO in the early stages of lichen rehydration.

【 授权许可】

CC BY   
© Catalá et al; licensee BioMed Central Ltd. 2010. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.