Progressive environmental deterioration in northwestern Pangea leading to the latest Permian extinction

Stratigraphic records from northwestern Pangea provide unique insight into global processes that occurred during the latest Permian extinction (LPE). We examined a detailed geochemical record of the Festningen section, Spitsbergen. A stepwise extinction is noted as: starting with (1) loss of carbonate shelly macrofauna, followed by (2) loss of siliceous sponges in conjunction with an abrupt change in ichnofabrics as well as dramatic change in the terrestrial environment, and (3) final loss of all trace fossils. We interpret loss of carbonate producers as related to shoaling of the lysocline in higher latitudes, in relationship to building atmospheric CO2. The loss of siliceous sponges is coincident with the global LPE event and is related to onset of high loading rates of toxic metals (Hg, As, Co) that we suggest are derived from Siberian Trap eruptions. The final extinction stage is coincident with redox-sen- sitive trace metal and other proxy data that suggest onset of anoxia after the other extinction events. These results show a remarkable record of progressive environmental deterioration in northwestern Pangea during the extinction crises

Sequence stratigraphy, basin morphology and sea-level history for the Permian Kapp Starostin Formation of Svalbard, Norway

Based on seven measured sections from Svalbard, the marine strata of the Permian Kapp Starostin Formation are arranged into seven transgressive–regressive sequences (TR1–TR7) of c. 4–5 Ma average duration, each bound by a maximum regressive surface. Facies, including heterozoan-dominated limestones, spiculitic cherts, sandstones, siltstones and shales, record deposition within inner, middle and outer shelf areas. The lowermost sequence, TR1, comprises most of the basal Vøringen Member, which records a transgression across the Gipshuken Formation following a hiatus of unknown duration. Temperate to cold, storm-dominated facies established in inner to middle shelf areas between the latest Artinskian and Kungurian. Prolonged deepening during sequences TR2 and TR3 was succeeded by a long-term shallowing-upward trend that lasted until the latest Permian (TR4–TR7). A major depocentre existed in central and western Spitsbergen while to the north, Dickson Land remained a shallow platform, leading to a shallow homoclinal ramp in NE Spitsbergen and Nordaustlandet. The Middle Permian extinction (late Capitanian) is recorded near the base of TR6 in deeper parts of the basin only; elsewhere this sequence is not recorded. Likewise the youngest sequence, TR7, extending to the upper formational contact of latest Permian age, is found only in the basin depocentre. Comparison with age-equivalent strata in the Sverdrup Basin of Canada reveals a remarkably similar depositional history, with, for example, two (third-order) sea-level cycles recorded in the Late Permian of both regions, in keeping with the global record. Sequence stratigraphy may therefore be a powerful correlative tool for onshore and offshore Permian deposits across NW Pangaea

NERNST: a genetically-encoded ratiometric non-destructive sensing tool to estimate NADP(H) redox status in bacterial, plant and animal systems

NADP(H) is a central metabolic hub providing reducing equivalents to multiple biosynthetic, regulatory and antioxidative pathways in all living organisms. While biosensors are available to determine NADP+ or NADPH levels in vivo, no probe exists to estimate the NADP(H) redox status, a determinant of the cell energy availability. We describe herein the design and characterization of a genetically-encoded ratiometric biosensor, termed NERNST, able to interact with NADP(H) and estimate E NADP(H). NERNST consists of a redox-sensitive green fluorescent protein (roGFP2) fused to an NADPH-thioredoxin reductase C module which selectively monitors NADP(H) redox states via oxido-reduction of the roGFP2 moiety. NERNST is functional in bacterial, plant and animal cells, and organelles such as chloroplasts and mitochondria. Using NERNST, we monitor NADP(H) dynamics during bacterial growth, environmental stresses in plants, metabolic challenges to mammalian cells, and wounding in zebrafish. NERNST estimates the NADP(H) redox poise in living organisms, with various potential applications in biochemical, biotechnological and biomedical research

NERNST: a genetically-encoded ratiometric non-destructive sensing tool to estimate NADP(H) redox status in bacterial, plant and animal systems

NADP(H) is a central metabolic hub providing reducing equivalents to multiple biosynthetic, regulatory and antioxidative pathways in all living organisms. While biosensors are available to determine NADP+ or NADPH levels in vivo, no probe exists to estimate the NADP(H) redox status, a determinant of the cell energy availability. We describe herein the design and characterization of a genetically-encoded ratiometric biosensor, termed NERNST, able to interact with NADP(H) and estimate ENADP(H). NERNST consists of a redox-sensitive green fluorescent protein (roGFP2) fused to an NADPH-thioredoxin reductase C module which selectively monitors NADP(H) redox states via oxidoreduction of the roGFP2 moiety. NERNST is functional in bacterial, plant and animal cells, and organelles such as chloroplasts and mitochondria. Using NERNST, we monitor NADP(H) dynamics during bacterial growth, environmental stresses in plants, metabolic challenges to mammalian cells, and wounding in zebrafish. NERNST estimates the NADP(H) redox poise in living organisms, with various potential applications in biochemical, biotechnological and biomedical research.Fil: Molinari, Pamela Estefanía. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: Krapp, Adriana. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: Weiner, Andrea María Julia. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: López, Melina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: Bustos Sanmamed, Pilar. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: Tevere, Evelyn. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: Calcaterra, Nora B. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: Carrillo, Néstor. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET); Argentina.Fil: Beyer, Hannes M. University of Düsseldorf. Institute of Synthetic Biology; Germany.Fil: Blomeier, Tim.University of Düsseldorf. Institute of Synthetic Biology; Germany.Fil: Zurbriggen, Matias D. University of Düsseldorf. Institute of Synthetic Biology; Germany.Fil: Kondadi, Arun Kumar. Heinrich-Heine-University Düsseldor. Medical Faculty and University Hospital Düsseldorf. Institute of Biochemistry and Molecular Biology I; Germany.Fil: Reichert, Andreas S. Heinrich-Heine-University Düsseldor. Medical Faculty and University Hospital Düsseldorf. Institute of Biochemistry and Molecular Biology I; Germany.Fil: Weber, Wilfried. University of Freiburg. Faculty of Biology and Signalling Research Centres BIOSS and CIBSS; Germany.Fil: Beller, Mathias. University of Düsseldorf. Institute of Mathematical Modeling of Biological Systems; Germany.Fil: Zurbriggen, Matias D. Cluster of Excellence on Plant Sciences; Germany.Fil: Weber, Wilfried. Saarland University. Leibniz Institute for New Materials and Department of Materials Sciences and Engineering; Germany

COP1 destabilizes DELLA proteins in Arabidopsis

DELLA transcriptional regulators are central components in the control of plant growth responses to the environment. This control is considered to be mediated by changes in the metabolism of the hormones gibberellins (GAs), which promote the degradation of DELLAs. However, here we show that warm temperature or shade reduced the stability of a GA-insensitive DELLA allele in Arabidopsis thaliana. Furthermore, the degradation of DELLA induced by the warmth preceded changes in GA levels and depended on the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1). COP1 enhanced the degradation of normal and GA-insensitive DELLA alleles when coexpressed in Nicotiana benthamiana. DELLA proteins physically interacted with COP1 in yeast, mammalian, and plant cells. This interaction was enhanced by the COP1 complex partner SUPRESSOR OF phyA-105 1 (SPA1). The level of ubiquitination of DELLA was enhanced by COP1 and COP1 ubiquitinated DELLA proteins in vitro. We propose that DELLAs are destabilized not only by the canonical GA-dependent pathway but also by COP1 and that this control is relevant for growth responses to shade and warm temperature.This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness and Agencia Española de Investigación/Fondo Europeo para el Desarrollo Regional/Unión Europea (grants BIO2016-79133-P to D.A. and BIO2013-46539-R and BIO2016-80551-R to V.R.); the European Union SIGNAT-Research and Innovation Staff Exchange (Grant H2020-MSCA-RISE-2014-644435 to M.A.B., D.A., and J.J.C.); the Argentinian Agencia Nacional de Promoción Científica y Tecnológica (Grant Proyectos de Investigación Científica y Tecnológica-2016-1459 to J.J.C.); Universidad de Buenos Aires (grant 20020170100505BA to J.J.C.); the National Institute of General Medical Sciences of the National Institutes of Health (awards R01GM067837 and R01GM056006 to S.A.K.); the German Research Foundation (DFG) under Germany’s Excellence Strategy/Initiative (Cluster of Excellence on Plant Sciences – Excellence Cluster EXC-2048/1, Project ID 390686111 to M.D.Z.); the International Max Planck Research School of the Max Planck Society; the Universities of Düsseldorf and of Cologne to T.B.; Nordrhein Westfalen Bioeconomy Science Center-FocusLabs CombiCom to N.H. and M.D.Z.; and Ministry of Education, Youth and Sports of the Czech Republic (Project LQ1601 Central European Institute of Technology 2020 to B.B. and M.C.). N.B.-T., E.I., and M.G.-L. were supported by Ministerio de Economía y Competitividad-Formación de Personal Investigador Program fellowships

COP1 destabilizes DELLA proteins in Arabidopsis

DELLA transcriptional regulators are central components in the control of plant growth responses to the environment. This control is considered to be mediated by changes in the metabolism of the hormones gibberellins (GAs), which promote the degradation of DELLAs. However, here we show that warm temperature or shade reduced the stability of a GA-insensitive DELLA allele in Arabidopsis thaliana. Furthermore, the degradation of DELLA induced by the warmth preceded changes in GA levels and depended on the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1). COP1 enhanced the degradation of normal and GAinsensitive DELLA alleles when coexpressed in Nicotiana benthamiana. DELLA proteins physically interacted with COP1 in yeast, mammalian, and plant cells. This interaction was enhanced by the COP1 complex partner SUPRESSOR OF phyA-105 1 (SPA1). The level of ubiquitination of DELLA was enhanced by COP1 and COP1 ubiquitinated DELLA proteins in vitro. We propose that DELLAs are destabilized not only by the canonical GA-dependent pathway but also by COP1 and that this control is relevant for growth responses to shade and warm temperature.Fil: Blanco Touriñán, Noel. Universidad Politécnica de Valencia; EspañaFil: Legris, Martina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Minguet, Eugenio G.. Universidad Politécnica de Valencia; EspañaFil: Costigliolo Rojas, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Nohales, María A.. University of Southern California; Estados UnidosFil: Iniesto, Elisa. Consejo Superior de Investigaciones Científicas; EspañaFil: García León, Marta. Consejo Superior de Investigaciones Científicas; EspañaFil: Pacín, Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Heucken, Nicole. Universitat Dusseldorf; AlemaniaFil: Blomeier, Tim. Universitat Dusseldorf; AlemaniaFil: Locascio, Antonella. Universidad Politécnica de Valencia; EspañaFil: Cerný, Martin. Mendel University in Brno; República ChecaFil: Esteve Bruna, David. Universidad Politécnica de Valencia; EspañaFil: Díez Díaz, Mónica. Univerdiad Catolica de Valencia; EspañaFil: Brzobohatý, Bretislav. Mendel University in Brno; República ChecaFil: Frerigmann, Henning. Max Planck Institute for Plant Breeding Research; AlemaniaFil: Zurbriggen, Matías D.. Universitat Dusseldorf; AlemaniaFil: Kay, Steve A.. University of Southern California; Estados UnidosFil: Rubio, Vicente. Consejo Superior de Investigaciones Científicas; EspañaFil: Blázquez, Miguel A.. Universidad Politécnica de Valencia; EspañaFil: Casal, Jorge José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Alabadí, David. Universidad Politécnica de Valencia; Españ

The Use of Biomaterials in Islet Transplantation

Pancreatic islet transplantation is a therapeutic option to replace destroyed β cells in autoimmune diabetes. Islets are transplanted into the liver via the portal vein; however, inflammation, the required immunosuppression, and lack of vasculature decrease early islet viability and function. Therefore, the use of accessory therapy and biomaterials to protect islets and improve islet function has definite therapeutic potential. Here we review the application of niche accessory cells and factors, as well as the use of biomaterials as carriers or capsules, for pancreatic islet transplantation

Facies architecture of a Lower Jurassic carbonate platform slope (Jbel Bou Dahar, High Atlas, Morocco)

The plateau of Jbel Bou Dahar (High Atlas, Morocco) represents an outstanding example of a well-preserved early Mesozoic carbonate platform. Field observations of the large-scale sedimentary structures and the arrangement of lithofacies associations within the mid- and lower slope were combined with detailed microfacies analyses and gamma-ray measurements. The investigations were carried out in order to (1) resolve the sequence stratigraphic architecture of the slope, and (2) reconstruct the sediment export patterns and depositional processes related to high-frequency sea-level variations. The slope strata are arranged into two different types of lithofacies associations that are bounded by characteristic discontinuities and show a specific occurrence along the investigated slope section. The steep (8-18°) mid-slope is dominated by thick- to medium-bedded limestone successions that were able to maintain a high angle of repose due to their detrital composition. The sediment packages are bounded by basal low-angle unconformities and wedge out within the lower slope or thin into the adjacent basin as single carbonate layers. The sediments are characterized by coarse-grained and poorly sorted floatstones to rudstones, which show low gamma-ray values and contain components derived mainly from the platform edge. The facies associations were interpreted as debris-flow deposits that were exported during sea-level lowstands when the flattened platform top and extended parts of the margin were exposed and sediment production was restricted mainly to the outer margin and upper slope section. In contrast, the gently dipping lower slope (4-18°) is characterized by rhythmic limestone-marl alternations that show increasing thicknesses with increasing distance from the platform. From the lower part of the mid-slope down, the successions onlap the debris-flow deposits, forming a characteristic interfingering pattern of different lithofacies associations. The medium- to thin-bedded carbonates of the limestone-marl alternations comprise two different microfacies types: (1) mudstones to wackestones with high gamma-ray values and a mixed shallow-marine to deep-marine microfacies, overlain by (2) well-sorted, arenitic packstones to grainstones with low gamma-ray values and a shallow-marine component composition. The latter points to the platform interior and margin as primary source areas. The shallow-marine material was exported during sea-level highstands when the carbonate factory included the entire platform margin and the flooded lagoons of the platform top. During these periods, the exported fine-grained sediments could maintain only low angles of repose. Thus they bypassed the steep upper and mid-slope sections, developed into turbidites during downslope transport, and were finally redeposited on the gently dipping lower slope and in the adjacent basin. The architecture of the investigated slope area shows a characteristic interfingering of different facies associations that can be interpreted as genetic highstand and lowstand stratigraphic sequences. The arrangement of these sequences along the slope, as well as their composition, were controlled by high-frequency sea-level fluctuations, affecting the primary sediment production (source area), export patterns, and sedimentary processes, resulting in a shift of the depositional centers during different sea-level stands

Acanthodian fish trace fossils from the Early Devonian of Spitsbergen

We describe and interpret Undichna septemsulcata isp. nov., from the fluvial Old Red Sandstone deposits of the Early Devonian Wood Bay Formation, of Northern Spitsbergen (Svalbard). Its delicate scratch pattern, comprising one unpaired median groove and three pairs of lateral grooves, all with a regular in−phase sinusoidal wave pattern of equal wavelength, allow the reconstruction of the number, position and relative spacing of the fins. The comparatively high−amplitude median groove is attributed to the main propelling action of the tail or caudal fin, the inner pair of the lateral grooves to the action of the pelvic fins, and the low−amplitude outer set of duplicate grooves to bifurcated pectoral fins, respectively. The in−phase geometric pattern is explained by a distance between the unpaired fin (caudal or anal fin) to the pectoral fins corresponding to one wavelength and a position of the pelvic fins half way in between. The direction of movement and the mode of locomotion of the trace maker (a carangiform to ostraciiform type) are deduced. This analysis is leading to an acanthodian (possibly Diplacanthus) as the most probable trace maker. By being Pragian or early Emsian (Early Devonian) in age, according to vertebrate and palynomorph biostratigraphy, these specimens are among the world’s oldest trace fossils made by a vertebrate