Article
Plant Sciences
Jochen M. Buck, Peter G. Kroth, Bernard Lepetit
Summary: Photosynthetic organisms have evolved various photoprotective mechanisms to prevent high light-induced photodamage, among which energy-dependent fluorescence quenching (qE) serves as a rapid way to dissipate excess absorbed energy. Diatoms, as important primary producers, utilize Lhcx proteins and the xanthophyll cycle pigment diatoxanthin to provide qE. By studying the mechanisms of qE in diatoms, it was found that specific amino acids and peptide motifs play crucial roles in conferring qE, with a tryptophan residue identified as having a major influence on qE establishment. This structural explanation sheds light on the intimate link between Lhcx proteins and diatoxanthin in providing qE in diatoms.
Article
Plant Sciences
Tomas E. van den Berg, Roberta Croce
Summary: A light-driven Xanthophyll cycle involving Lutein and Loroxanthin operates in Chlamydomonas reinhardtii, affecting the pigment content and spectroscopic properties of trimeric LHCII. The Loroxanthin cycle shows similarities to the Lutein-epoxide - Lutein cycle in plants and likely evolved as a shade adaptation.
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Microbiology
Jiale Qiu, Jie Zhang, Huihui Zhao, Cuiping Wu, Caoliang Jin, Xiangdong Hu, Jian Li, Xiuling Cao, Shenkui Liu, Xuejiao Jin
Summary: Carbonate stress has significant impacts on agriculture and industry, but the role of cell wall-related genes in resistance to carbonate remains poorly understood. This study reveals the critical role of cellulose in the NaHCO3 resistance of Chlorella JB17, and identifies a NaHCO3-tolerance gene that could be used for crop breeding and genetic modification of microalgae for biofuel production.
FRONTIERS IN MICROBIOLOGY
(2023)
Review
Cell Biology
Wojciech Pokora, Szymon Tulodziecki, Agnieszka Dettlaff-Pokora, Anna Aksmann
Summary: Reactive oxygen species (ROS) and reactive nitrogen species (RNS) play regulatory roles in the development of higher plants, algae, and animals. In green cells, the redox potential regulates growth rate. Hydrogen peroxide and nitric oxide directly participate in algal cell development by regulating the expression of proteins involved in the cell cycle. This regulation involves the interaction of these signaling molecules with redox-sensitive transcription factors and signaling pathways. This paper aims to elucidate the involvement of hydrogen peroxide and nitric oxide in algal cell cycle regulation and evaluate their commercial applicability.
Article
Plant Sciences
Guy Levin, Sharon Kulikovsky, Varda Liveanu, Benjamin Eichenbaum, Ayala Meir, Tal Isaacson, Yaakov Tadmor, Noam Adir, Gadi Schuster
Summary: While excessive light can harm photosynthesis by causing photoinhibition, certain microalgae like Chlorella ohadii have evolved mechanisms to resist this damage, including reducing PSII antenna size, accumulating protective carotenoids, and rapidly repairing damaged proteins. These mechanisms enable photosynthesis-dependent life in harsh environments.
Article
Plant Sciences
Guo Xie, Ke Ding, Wen-Li Liu, Zi-Yi Zheng, Yong-Gang Liu, Yong-Zhong Wang
Summary: The study demonstrated that lipid biosynthesis in Chlorella pyrenoidosa was enhanced under nutrient-deficiency stress conditions, resulting in a significant increase in intracellular lipid content. The expression levels of genes related to energy metabolism were downregulated, while those related to lipid synthesis were upregulated, indicating a potential involvement of the ROS signal pathway in mediating metabolic pathways during nutrient-deficiency stress.
Article
Plant Sciences
Maria-Lavrentia Stamelou, Ilektra Sperdouli, Ioanna Pyrri, Ioannis-Dimosthenis S. Adamakis, Michael Moustakas
Summary: Botrytis cinerea, a fungal pathogen causing gray mold, damages over 200 plant species, with a significant impact on tomatoes. Applying Botrytis spores to tomato leaves triggers a defense response mechanism, enhancing PSII functionality and potentially increasing plant defense potential through the induction of defense genes.
Article
Plant Sciences
Davide Gerna, Daniel Ballesteros, Erwann Arc, Wolfgang Stoeggl, Charlotte E. Seal, Nicki Marami-Zonouz, Chae Sun Na, Ilse Kranner, Thomas Roach
Summary: Seed ageing mechanisms are influenced by the physical state of the cytoplasm. Oxygen promotes lipid peroxidation and seed viability loss when the cytoplasm is glassy, but not when it is fluid. Hypoxic conditions delay seed deterioration, lipid peroxidation, and decline of antioxidants only when the cytoplasm is glassy. When the cytoplasm is fluid, seed deterioration occurs at the same rate regardless of oxygen availability, with limited lipid peroxidation and detoxification of lipid peroxide products.
JOURNAL OF EXPERIMENTAL BOTANY
(2022)
Article
Biotechnology & Applied Microbiology
Thomas Roach, Nina Boeck, Nina Rittmeier, Erwann Arc, Ilse Kranner, Andreas Holzinger
Summary: The study reveals that the desiccation tolerance in Haematococcus pluvialis is related to the color of the cells, with red cells showing better tolerance. The mechanisms of desiccation tolerance include changes in cell ultra-structure and synthesis of astaxanthin-rich lipid bodies. The processes of acclimation to desiccation under low and high light conditions have overlapping components, such as accumulation of fatty acids, lipid bodies, and astaxanthin. Atmospheric exposure alone can trigger acclimation to desiccation, and photosynthesis powers this process, but high light stress and dehydration are not strictly necessary.
ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
(2022)
Editorial Material
Plant Sciences
Thomas Roach, Eunchul Kim, Lijin Tian, Bernard Lepetit
FRONTIERS IN PLANT SCIENCE
(2022)
Article
Microbiology
Siegfried Aigner, Erwann Arc, Michael Schletter, Ulf Karsten, Andreas Holzinger, Ilse Kranner
Summary: This study reports on the responses and metabolic adjustments to light, temperature, and desiccation in two algal strains, D. epiphytica and E. mirabilis. The results show that the desiccation-tolerant strain D. epiphytica accumulated more compatible solutes, while the desiccation-sensitive strain C. vulgaris showed greater variation in metabolite accumulation after desiccation and rehydration. These findings are important for understanding the adaptation mechanisms of microalgae.
Article
Biotechnology & Applied Microbiology
Carlos Trujillo-Moya, Andrea Ganthaler, Wolfgang Stoeggl, Erwann Arc, Ilse Kranner, Silvio Schueler, Reinhard Ertl, Ana Espinosa-Ruiz, Maria Angeles Martinez-Godoy, Jan-Peter George, Stefan Mayr
Summary: This study investigated the defense and metabolic processes of resistant and susceptible genotypes of Norway spruce against needle rust disease. The key genes and metabolic pathways involved in spruce defense were identified, and the resistant genotype showed higher levels of resistance-related compounds.
Article
Plant Sciences
Guillaume Wos, Erwann Arc, Karl Huelber, Veronika Konecna, Adam Knotek, Doubravka Pozarova, Clara Bertel, Dominik Kaplenig, Terezie Mandakova, Gilbert Neuner, Peter Schoenswetter, Ilse Kranner, Filip Kolar
Summary: Parallel local adaptation, when different genetic lineages independently adapt to the same selective environment, was investigated in Arabidopsis arenosa populations from four distinct mountain regions. The study found that the populations exhibited similar adaptive responses to elevation difference, indicating parallel local adaptation. The results highlight the role of divergent selection and provide experimental support for the repeatability of adaptive evolution.
JOURNAL OF ECOLOGY
(2022)
Article
Plant Sciences
D. Kaplenig, C. Bertel, E. Arc, R. Villscheider, M. Ralser, F. Kolar, G. Wos, K. Huelber, I Kranner, G. Neuner
Summary: The success or failure of plants in coping with freezing temperatures is crucial for their distribution and adaptation in new habitats. This study focused on the differentiation in freezing resistance, cold acclimation potential, and ice management strategies in alpine and foothill populations of Arabidopsis arenosa, revealing the importance of dynamic adjustment and evolutionary history in plant adaptation to alpine environments. The formation of an extracellular ice lens as a mechanism to avoid tissue damage during freezing is a novel finding with potential implications for plant survival in extreme cold conditions.
Article
Plant Sciences
Regina Ninoles, Dolores Planes, Paloma Arjona, Carmen Ruiz-Pastor, Ruben Chazarra, Joan Renard, Eduardo Bueso, Javier Forment, Ramon Serrano, Ilse Kranner, Thomas Roach, Jose Gadea
Summary: Understanding the genetic factors involved in seed longevity is crucial in agriculture and ecology. This study investigated the mechanisms behind differing seed longevity in Arabidopsis thaliana, revealing the importance of redox poise and stored mRNA in determining seed viability. Multiple factors contribute to seed longevity, including heat-shock factors and RNA regulation.
PLANT CELL AND ENVIRONMENT
(2022)
Article
Plant Sciences
Thomas Roach, Theresa Baur, Ilse Kranner
Summary: The study found that singlet oxygen (O-1(2)) partially regulates light stress signaling in algae and plants, and beta-carotene molecules can quench O-1(2). In the unicellular alga Chlamydomonas reinhardtii, beta-cyclocitral may down-regulate chlorophyll synthesis, but it does not seem to contribute to O-1(2)-mediated high light stress signaling.
Review
Plant Sciences
Gregor Pichler, Lucia Muggia, Fabio Candotto Carniel, Martin Grube, Ilse Kranner
Summary: Lichens are unique fungal symbioses that can form a new structure together with photosynthetic partners. The signals involved in the transition from a free-living state to a symbiotic state, called lichenization, and the maintenance of the symbiosis are not well understood. This study synthesizes existing knowledge into a concept of signaling involved in lichenization, including five stages: pre-contact, contact, envelopment, incorporation, and differentiation. Compounds such as fungal lectins and algal cyclic peptides may initiate early contact, while phytohormone signaling, antioxidant protection, and carbon exchange are important throughout all stages.
Article
Plant Sciences
Richard Peter Beckett, Thomas Roach, Farida Minibayeva, Silke Werth
Summary: The photosynthetic apparatus of lichen photobionts, including cyclic electron flow and photoprotection, was studied using chlorophyll fluorescence analysis and near-infrared absorption. Sun species exhibited lower PSI acceptor side limitation and higher flavodiiron-mediated pseudocyclic electron flow compared to shade species. Melanised lichens had lower Y[NA], higher NDH-2-type cyclic flow, and higher non-photochemical quenching, while shade species displayed faster relaxing NPQ. Cyclic electron flow was a prominent feature in all lichens regardless of habitat.
PHYSIOLOGIA PLANTARUM
(2023)
Article
Biochemistry & Molecular Biology
Thomas Roach, Gilbert Neuner, Ilse Kranner, Othmar Buchner
Summary: Heat and drought stresses are important topics in the context of climate change, especially in the Alps. A study found that alpine plants can gradually adapt to heat and achieve maximum tolerance within a week. The antioxidant mechanisms of Primula minima leaves that were heat hardened without or with additional drought stress were investigated. The results showed a weakened low-molecular-weight antioxidant defense but increased activity of antioxidant enzymes, particularly under drought conditions.
Meeting Abstract
Biochemistry & Molecular Biology
Pablo Albertos, Immaculada Sanchez-Vicente, Jose Manuel Franco, Roberto Solano, David Gerna, Thomas Roach, Wolfgang Stoggl, Ilse Kranner, Julio Salina, Oscar Lorenzo
FREE RADICAL BIOLOGY AND MEDICINE
(2022)
Meeting Abstract
Biochemistry & Molecular Biology
Pablo Albertos, Maria Immaculada Sanchez-Vicente, Jose Manuel Franco, Roberto Solano, David Gerna, Thomas Roach, Wolfgang Stoggl, Ilse Kranner, Julio Salina, Oscar Lorenzo
FREE RADICAL BIOLOGY AND MEDICINE
(2022)