Diatom Molecular Research Comes of Age: Model Species for Studying Phytoplankton Biology and Diversity

The Plant Cell, Год журнала: 2019, Номер 32(3), С. 547 - 572

Опубликована: Дек. 18, 2019

Diatoms are the world's most diverse group of algae, comprising at least 100,000 species. Contributing ~20% annual global carbon fixation, they underpin major aquatic food webs and drive biogeochemical cycles. Over past two decades, Thalassiosira pseudonana Phaeodactylum tricornutum have become important model systems for diatom molecular research, ranging from cell biology to ecophysiology, due their rapid growth rates, small genomes, cumulative wealth associated genetic resources. To explore evolutionary divergence diatoms, additional species emerging, such as Fragilariopsis cylindrus Pseudo-nitzschia multistriata. Here, we describe how functional genomics reverse genetics contributed our understanding this class microalgae in context evolution, biology, metabolic adaptations. Our review will also highlight promising areas investigation into diversity these photosynthetic organisms, including discovery new pathways governing life secondary plastid-bearing organisms environments.

Язык: Английский

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Light harvesting complexes in chlorophyll c-containing algae

Biochimica et Biophysica Acta (BBA) - Bioenergetics, Год журнала: 2019, Номер 1861(4), С. 148027 - 148027

Опубликована: Май 31, 2019

Язык: Английский

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Lhcx proteins provide photoprotection via thermal dissipation of absorbed light in the diatom Phaeodactylum tricornutum

Nature Communications, Год журнала: 2019, Номер 10(1)

Опубликована: Сен. 13, 2019

Abstract Diatoms possess an impressive capacity for rapidly inducible thermal dissipation of excess absorbed energy (qE), provided by the xanthophyll diatoxanthin and Lhcx proteins. By knocking out Lhcx1 Lhcx2 genes individually in Phaeodactylum tricornutum strain 4 complementing knockout lines with different proteins, multiple mutants varying qE capacities are obtained, ranging from zero to high values. We demonstrate that is entirely dependent on concerted action Lhcx1, Lhcx3 having similar functions. Moreover, we establish a clear link between Lhcx1/2/3 mediated reduction functional absorption cross-section photosystem II. This regulation can be tuned altered protein expression response environmental conditions. Our results provide holistic understanding process its mechanistic implications diatoms.

Язык: Английский

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Thoughts on the evolution and ecological niche of diatoms

Ecological Monographs, Год журнала: 2021, Номер 91(3)

Опубликована: Апрель 30, 2021

Abstract Diatoms are the most recent major algal lineage added to geological record, appearing more than 200 million years ago. They stramenopile protists resulting from a secondary endosymbiotic event that yielded only photosynthetic protistan expressing external siliceous cell wall structures called frustules. Many diatoms also have large internal vacuoles, and common assumption in literature is success of largely attributable these two morphological inventions: frustule for defense vacuole luxury nutrient uptake. Here, we revisit evolution inventions, propose sequential steps development, replace uptake with predator buoyancy control as driver expansion, suggest perhaps greatest significance diatom consequence enhancing sexual reproduction. In this synthesis, emphasize distinction between “general” “bloom‐forming” species, physiological drivers successes differ. Importantly, bloom‐forming species responsible role aquatic biogeochemical cycles. The habit ascribe specific attributes that, at their core, revolve around influencing balance growth losses predators. We adaptations linked size‐dependent maximum division rates diatoms, because size scaling predator–prey interactions. existence yields an apparent allometric relationship has previously been interpreted terms acquisition. Our analysis insights into successions during blooms, considers fundamental benefit blooming (and subsequent sinking) reproductive standpoint, provides some reinterpretation over geologic time modern ocean.

Язык: Английский

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Modulation of xanthophyll cycle impacts biomass productivity in the marine microalga Nannochloropsis

Proceedings of the National Academy of Sciences, Год журнала: 2023, Номер 120(25)

Опубликована: Июнь 12, 2023

Life on earth depends photosynthetic primary producers that exploit sunlight to fix CO2 into biomass. Approximately half of global production is associated with microalgae living in aquatic environments. Microalgae also represent a promising source biomass complement crop cultivation, and they could contribute the development more sustainable bioeconomy. Photosynthetic organisms evolved multiple mechanisms involved regulation photosynthesis respond highly variable environmental conditions. While essential avoid photodamage, results dissipation absorbed light energy, generating complex trade-off between protection from stress light-use efficiency. This work investigates impact xanthophyll cycle, light-induced reversible conversion violaxanthin zeaxanthin, excess productivity marine genus Nannochloropsis. Zeaxanthin shown have an role light, contributing induction nonphotochemical quenching scavenging reactive oxygen species. On contrary, overexpression zeaxanthin epoxidase enables faster reconversion be advantageous for dense cultures photobioreactors. These demonstrate accumulation critical strong illumination, but it may lead unnecessary energy losses light-limiting conditions accelerating its provides advantage microalgae.

Язык: Английский

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Diversity in Xanthophyll Cycle Pigments Content and Related Nonphotochemical Quenching (NPQ) Among Microalgae: Implications for Growth Strategy and Ecology

Journal of Phycology, Год журнала: 2019, Номер 56(2), С. 245 - 263

Опубликована: Ноя. 1, 2019

Xanthophyll cycle‐related nonphotochemical quenching ( NPQ ), which is present in most photoautotrophs, allows dissipation of excess light energy. depends principally on xanthophyll cycle pigments composition and their effective involvement . tightly controlled by environmental conditions a species‐/strain‐specific manner. These features are especially relevant microalgae living complex highly variable environment. The goal this study was to perform comparative assessment ecophysiologies across microalgal taxa order underline the specific growth adaptations strategies. We used both published results data acquired our laboratory understand relationships between (irradiance, temperature, nutrient availability), composition, efficiency from various taxa. found that diadinoxanthin‐containing species, pigment pool energy pressure all species. At any given pressure, however, diatoxanthin content higher diatoms than other XC species‐specific decreases with acclimation irradiances. clear link natural environment species/ecotypes amplitude. presence or zeaxanthin at steady state species examined moderate high irradiances suggests cells maintain light‐harvesting capacity cope potential decrease intensity.

Язык: Английский

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A fast and reliable strategy to generate TALEN-mediated gene knockouts in the diatom Phaeodactylum tricornutum

Algal Research, Год журнала: 2017, Номер 23, С. 186 - 195

Опубликована: Фев. 20, 2017

Язык: Английский

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Dynamic Changes between Two LHCX-Related Energy Quenching Sites Control Diatom Photoacclimation

PLANT PHYSIOLOGY, Год журнала: 2018, Номер 177(3), С. 953 - 965

Опубликована: Май 17, 2018

Marine diatoms are prominent phytoplankton organisms that perform photosynthesis in extremely variable environments. Diatoms possess a strong ability to dissipate excess absorbed energy as heat via nonphotochemical quenching (NPQ). This process relies on changes carotenoid pigment composition (xanthophyll cycle) and specific members of the light-harvesting complex family specialized photoprotection (LHCXs), which potentially act NPQ effectors. However, link between light stress, NPQ, existence different LHCX isoforms is not understood these organisms. Using picosecond fluorescence analysis, we observed two types pennate diatom Phaeodactylum tricornutum were dependent conditions. Short exposure low-light-acclimated cells high triggers onset close core photosystem II, while prolonged stress activates antenna. Biochemical analysis indicated site/mechanism induction isoforms, accumulate either antenna complexes or complex. By comparing responses wild-type transgenic lines with reduced expression major isoform, LHCX1, conclude complex-associated more effective than Overall, our data clarify molecular scenario provide rationale for degenerate proteins algae.

Язык: Английский

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Toward Enhanced Fixation of CO2 in Aquatic Biomass: Focus on Microalgae

Frontiers in Energy Research, Год журнала: 2020, Номер 8

Опубликована: Сен. 16, 2020

The need to reduce the CO2 footprint of human activities calls for utilization new means production and sources products. Microalgae are a very promising source large variety products, from fuels chemicals multiple industrial applications (e.g. dies, pharmaceutical cosmetics, food feed, materials high tech manufacture), processes such as wastewater treatment. Algae, photosynthetic organisms, use light energize synthesis organic matter differently most terrestrial plants, can be cultured on land that not used crop production. We describe main factors contributing microalgae productivity in artificial cultivation systems discuss research areas still investigation order pave way generation cell factories. shall comment caveats possible mode improving efficiency optimize partitioning fixed C products commercial relevance. address problem selection appropriate strain consequences their diverse physiology culture conditions successful application. Finally, we provide state art information factories chassis by synthetic biology approaches produce interest.

Язык: Английский

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Morpho‐anatomical and physiological differences between sun and shade leaves in Abies alba Mill. (Pinaceae, Coniferales): a combined approach

Plant Cell & Environment, Год журнала: 2018, Номер 41(7), С. 1683 - 1697

Опубликована: Апрель 17, 2018

Abstract Morphology, anatomy and physiology of sun shade leaves Abies alba were investigated major differences identified, such as being larger, containing a hypodermis palisade parenchyma well possessing more stomata, while exhibit distinct leaf dimorphism. The large size their arrangement crowded on the upper side plagiotropic shoot leads to self‐shading which is explainable protection from high solar radiation reduce transpiration via lamina. Sun furthermore contain higher xanthophyll cycle pigment amount Non‐Photochemical Quenching (NPQ) capacity, lower chlorophyll b total per leaf, an increased electron transport rate photosynthesis light saturation intensity. However, switch NPQ capacity at rather low intensities, exemplified by several parameters newly measured for conifers. Our holistic approach extends previous findings about in conifers demonstrates that both types A. show structural physiological remarkable similarities respective counterparts angiosperms, but also possess unique characteristics allowing them cope efficiently with environmental constraints.

Язык: Английский

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