Time me by the moon : The evolution and function of lunar timing systems.

The moon has significant impact on the timing of organisms. Can the study of molecular timing mechanisms of marine animals and algae help to understand some of the “weird” correlations between human physiological/behavioral rhythms and the lunar cycle? [Image: see text]

A redundant transcription factor network steers spatiotemporal Arabidopsis triterpene synthesis.

Plant specialized metabolites modulate developmental and ecological functions and comprise many therapeutic and other high-value compounds. However, the mechanisms determining their cell-specific expression remain unknown. Here we describe the transcriptional regulatory network that underlies cell-specific biosynthesis of triterpenes in Arabidopsis thaliana root tips.

A network of stress-related genes regulates hypocotyl elongation downstream of selective auxin perception.

The plant hormone auxin, a master coordinator of development, regulates hypocotyl elongation during seedling growth. We previously identified the synthetic molecule RubNeddin 1 (RN1), which induces degradation of the AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) transcriptional repressors INDOLE-3-ACETIC ACID-INDUCIBLE3 (IAA3) and IAA7 in planta and strongly promotes hypocotyl elongation. In the present study, we show that despite the structural similarity of RN1 to the synthetic auxin 2,4-dichlorophenoxyacetic-acid (2,4-D), direct treatments with these compounds in Arabidopsis (Arabidopsis thaliana) result in distinct effects, possibly due to enhanced uptake of RN1 and low-level, chronic release of 2,4-D from RN1 in planta.

Modulation of Arabidopsis root growth by specialized triterpenes.

Plant roots are specialized belowground organs that spatiotemporally shape their development in function of varying soil conditions. This root plasticity relies on intricate molecular networks driven by phytohormones, such as auxin and jasmonate (JA). Loss-of-function of the NOVEL INTERACTOR OF JAZ (NINJA), a core component of the JA signaling pathway, leads to enhanced triterpene biosynthesis, in particular of the thalianol gene cluster, in Arabidopsis thaliana roots.

Breaking Bad News: Dynamic Molecular Mechanisms of Wound Response in Plants.

Recognition and repair of damaged tissue are an integral part of life. The failure of cells and tissues to appropriately respond to damage can lead to severe dysfunction and disease. Therefore, it is essential that we understand the molecular pathways of wound recognition and response.

FRS7 and FRS12 recruit NINJA to regulate expression of glucosinolate biosynthesis genes.

The sessile lifestyle of plants requires accurate physiology adjustments to be able to thrive in a changing environment. Plants integrate environmental timing signals to control developmental and stress responses. Here, we identified Far1 Related Sequence (FRS) 7 and FRS12, two transcriptional repressors that accumulate in short-day conditions, as regulators of Arabidopsis glucosinolate (GSL) biosynthesis.

bHLH-PAS protein RITMO1 regulates diel biological rhythms in the marine diatom .

Periodic light-dark cycles govern the timing of basic biological processes in organisms inhabiting land as well as the sea, where life evolved. Although prominent marine phytoplanktonic organisms such as diatoms show robust diel rhythms, the mechanisms regulating these processes are still obscure. By characterizing a bHLH-PAS nuclear protein, hereby named RITMO1, we shed light on the regulation of the daily life of diatoms.

Peptimapper: proteogenomics workflow for the expert annotation of eukaryotic genomes.

Background: Accurate structural annotation of genomes is still a challenge, despite the progress made over the past decade. The prediction of gene structure remains difficult, especially for eukaryotic species, and is often erroneous and incomplete. We used a proteogenomics strategy, taking advantage of the combination of proteomics datasets and bioinformatics tools, to identify novel protein coding-genes and splice isoforms, assign correct start sites, and validate predicted exons and genes.

Genome editing in diatoms: achievements and goals.

Diatoms are major components of phytoplankton and play a key role in the ecology of aquatic ecosystems. These algae are of great scientific importance for a wide variety of research areas, ranging from marine ecology and oceanography to biotechnology. During the last 20 years, the availability of genomic information on selected diatom species and a substantial progress in genetic manipulation, strongly contributed to establishing diatoms as molecular model organisms for marine biology research.

Author Correction: The transcriptional repressor complex FRS7-FRS12 regulates flowering time and growth in Arabidopsis.

This corrects the article DOI: 10.1038/ncomms15235.

Herbivore-induced chemical and molecular responses of the kelps Laminaria digitata and Lessonia spicata.

Kelps are founding species of temperate marine ecosystems, living in intertidal coastal areas where they are often challenged by generalist and specialist herbivores. As most sessile organisms, kelps develop defensive strategies to restrain grazing damage and preserve their own fitness during interactions with herbivores. To decipher some inducible defense and signaling mechanisms, we carried out metabolome and transcriptome analyses in two emblematic kelp species, Lessonia spicata from South Pacific coasts and Laminaria digitata from North Atlantic, when challenged with their main specialist herbivores.

Glutaredoxin GRXS17 Associates with the Cytosolic Iron-Sulfur Cluster Assembly Pathway.

Cytosolic monothiol glutaredoxins (GRXs) are required in iron-sulfur (Fe-S) cluster delivery and iron sensing in yeast and mammals. In plants, it is unclear whether they have similar functions. Arabidopsis (Arabidopsis thaliana) has a sole class II cytosolic monothiol GRX encoded by GRXS17 Here, we used tandem affinity purification to establish that Arabidopsis GRXS17 associates with most known cytosolic Fe-S assembly (CIA) components.

The Arabidopsis Iron-Sulfur Protein GRXS17 is a Target of the Ubiquitin E3 Ligases RGLG3 and RGLG4.

The stability of signaling proteins in eukaryotes is often controlled by post-translational modifiers. For polyubiquitination, specificity is assured by E3 ubiquitin ligases. Although plant genomes encode hundreds of E3 ligases, only few targets are known, even in the model Arabidopsis thaliana.

The RING E3 Ligase KEEP ON GOING Modulates JASMONATE ZIM-DOMAIN12 Stability.

Jasmonate (JA) signaling in plants is mediated by the JASMONATE ZIM-DOMAIN (JAZ) proteins that repress the activity of several transcription factors regulating JA-inducible gene expression. The hormone JA-isoleucine triggers the interaction of JAZ repressor proteins with the F-box protein CORONATINE INSENSITIVE1 (COI1), part of an S-phase kinase-associated protein1/Cullin1/F-box protein COI1 (SCF(COI1)) E3 ubiquitin ligase complex, and their degradation by the 26S proteasome. In Arabidopsis (Arabidopsis thaliana), the JAZ family consists of 13 members.

Transcriptomic and metabolomic analysis of copper stress acclimation in Ectocarpus siliculosus highlights signaling and tolerance mechanisms in brown algae.

Background: Brown algae are sessile macro-organisms of great ecological relevance in coastal ecosystems. They evolved independently from land plants and other multicellular lineages, and therefore hold several original ontogenic and metabolic features. Most brown algae grow along the coastal zone where they face frequent environmental changes, including exposure to toxic levels of heavy metals such as copper (Cu).

Cellular effects of bacterial N-3-Oxo-dodecanoyl-L-Homoserine lactone on the sponge Suberites domuncula (Olivi, 1792): insights into an intimate inter-kingdom dialogue.

Sponges and bacteria have lived together in complex consortia for 700 million years. As filter feeders, sponges prey on bacteria. Nevertheless, some bacteria are associated with sponges in symbiotic relationships.

Proteomic studies highlight outer-membrane proteins related to biofilm development in the marine bacterium Pseudoalteromonas sp. D41.

Bacterial biofilm development is conditioned by complex processes involving bacterial attachment to surfaces, growth, mobility, and exoproduct production. The marine bacterium Pseudoalteromonas sp. strain D41 is able to attach strongly onto a wide variety of substrates, which promotes subsequent biofilm development.

The Ectocarpus genome and the independent evolution of multicellularity in brown algae.

Brown algae (Phaeophyceae) are complex photosynthetic organisms with a very different evolutionary history to green plants, to which they are only distantly related. These seaweeds are the dominant species in rocky coastal ecosystems and they exhibit many interesting adaptations to these, often harsh, environments. Brown algae are also one of only a small number of eukaryotic lineages that have evolved complex multicellularity (Fig.

Copper stress proteomics highlights local adaptation of two strains of the model brown alga Ectocarpus siliculosus.

Ectocarpus siliculosus is a cosmopolitan brown alga with capacity to thrive in copper enriched environments. Analysis of copper toxicity was conducted in two strains of E. siliculosus isolated from (i) an uncontaminated coast in southern Peru (Es32) and (ii) a copper polluted rocky beach in northern Chile (Es524).

Release of volatile aldehydes by the brown algal kelp Laminaria digitata in response to both biotic and abiotic stress.

With a little kelp from my friends: In response to biotic and abiotic stress, the brown algal kelp Laminaria digitata releases volatile fatty acid aldehydes under laboratory conditions and in its natural environment (red). In response to 4-HHE treatment, L. digitata releases (13S)-HOTrE (green).

TWO-DIMENSIONAL GEL ELECTROPHORESIS ANALYSIS OF BROWN ALGAL PROTEIN EXTRACTS(1).

High-quality protein extracts are required for proteomic studies, a field that is poorly developed for marine macroalgae. A reliable phenol extraction protocol using Scytosiphon gracilis Kogame and Ectocarpus siliculosus (Dillwyn) Lyngb. (Phaeophyceae) as algal models resulted in high-quality protein extracts.

Copper stress induces biosynthesis of octadecanoid and eicosanoid oxygenated derivatives in the brown algal kelp Laminaria digitata.

To better understand the toxicity and the orchestration of antioxidant defenses of marine brown algae in response to copper-induced stress, lipid peroxidation processes were investigated in the brown alga Laminaria digitata. The expression of genes involved in cell protection and anti-oxidant responses were monitored by semi-quantitative reverse transcriptase polymerase chain reaction and the lipid peroxidation products were further characterized by profiling oxylipin signatures using high-pressure liquid chromatography-mass spectrometry. Exposure to copper excess triggers lipoperoxide accumulation and upregulates the expression of stress related genes.