In planta function of compatible solute transporters of the AtProT family

The three proline transporters of Arabidopsis thaliana (AtProTs) transport the compatible solutes proline and glycine betaine and the stress-induced compound γ-aminobutyric acid when expressed in heterologous systems. The aim of the present study was to show transport and physiological relevance of these three AtProTs in planta. Using single, double, and triple knockout mutants and AtProT-overexpressing lines, proline content, growth on proline, transport of radiolabelled betaine, and expression of AtProT genes and enzymes of proline metabolism were analysed. AtProT2 was shown to facilitate uptake of L- and D-proline as well as [14C]glycine betaine in planta, indicating a role in the import of compatible solutes into the root. Toxic concentrations of L- and D-proline resulted in a drastic growth retardation of AtProT-overexpressing plants, demonstrating the need for a precise regulation of proline uptake and/or distribution. Furthermore evidence is provided that AtProT genes are highly expressed in tissues with elevated proline content—that is, pollen and leaf epidermi

In planta function of compatible solute transporters of the AtProT family

The three proline transporters of Arabidopsis thaliana (AtProTs) transport the compatible solutes proline and glycine betaine and the stress-induced compound γ-aminobutyric acid when expressed in heterologous systems. The aim of the present study was to show transport and physiological relevance of these three AtProTs in planta. Using single, double, and triple knockout mutants and AtProT-overexpressing lines, proline content, growth on proline, transport of radiolabelled betaine, and expression of AtProT genes and enzymes of proline metabolism were analysed. AtProT2 was shown to facilitate uptake of L- and D-proline as well as [14C]glycine betaine in planta, indicating a role in the import of compatible solutes into the root. Toxic concentrations of L- and D-proline resulted in a drastic growth retardation of AtProT-overexpressing plants, demonstrating the need for a precise regulation of proline uptake and/or distribution. Furthermore evidence is provided that AtProT genes are highly expressed in tissues with elevated proline content—that is, pollen and leaf epidermis

Detailed evaluation of technologies for the pilot scale pyrolysis of plastic wastes

In Switzerland, as in some other industrialized countries, plastic wastes are eliminated together with municipal wastes by incineration with thermal energy recovery (“ITER”) for power production and district heating. However, although this is thought as one of the best methods to dispose of the wastes, the trend is for increased sorting, separate collection, and material recycling as it is already the case for PET bottles. In this context, an ambitious project is carried out by a group of industrial and R&D partners to find an innovative and complementary alternative with a strong ecological, economic, and societal impact. The first phase, now completed, aimed at the comparison of best available pyrolysis technologies for distributed energy conversion plants which should be 10 times smaller or less than ITER plants. The objective is to implement on a pilot scale a pyrolysis unit which should allow better energy recovery and thus contribute to the energy transition. Several typical wastes already collected separately were considered for a 1500 t/year pilot plant : The considered alternatives were technologies that produce liquid and/or gaseous fuels such as pyrolysis or gasification. The objective of the feasibility study was to evaluate the different options in terms of ecological, economic, and social impact for the recovery of plastic waste by comparing them to the existing solution, namely incineration with thermal energy recovery (“ITER”). Only high-temperature pyrolysis or pyrogasification technologies were found to meet the technical requirements, types of waste and quantities to be treated and the environmental criteria of this project with half the GHG emissions and fossil fuel utilization compared to incinerators. This project can serve as a model for the valorization of plastics in the future. It is important to stress that the deployment of these new technologies is complementary (and not in competition) to ITER, with a view to a transition of the latter towards a circular economy in the coming decades

Adrenocortical oncocytoma in a child

Adrenocortical oncocytoma is a rare epithelial tumor only described in adults. We report the case of a 12-year-old female who presented a left adrenal mass with abdominal pain, fatigue, acne vulgaris, and elevation of the androstenedione and total testosterone. She had an adrenalectomy. A diagnosis of adrenocortical oncocytoma was made after detailed histological, immunohistochemical, and ultrastructural studies

The Arabidopsis TSPO-related protein is a stress and abscisic acid-regulated, ER-Golgi-localized membrane protein

Summary The Arabidopsis gene At2g47770 encodes a membrane-bound protein designated AtTSPO (Arabidopsis thaliana TSPO-related). AtTSPO is related to the bacterial outer membrane tryptophan-rich sensory protein (TspO) and the mammalian mitochondrial 18 kDa Translocator Protein (18 kDa TSPO), members of the TspO/MBR domain-containing membrane proteins. In this study we showed that AtTSPO is mainly detected in dry seeds, but can be induced in vegetative tissues by osmotic or salt stress or abscisic acid treatment, corroborating available transcriptome data. Using subcellular fractionation, immunocytochemistry, and fluorescent protein tagging approaches we present evidence that AtTSPO is targeted to the secretory pathway in plant. Induced or constitutively expressed AtTSPO can be detected in the endoplasmic reticulum and the Golgi stacks of plant cell. AtTSPO tagged with fluorescent protein in transgenic plant (Arabidopsis and tobacco) was mainly detected in Golgi stacks of leaf epidermal cells. Constitutive expression of AtTSPO resulted in increased sensitivity to NaCl, but not to osmotic stress, and in reduced greening of cultured Arabidopsis cells under light growing conditions. Transgenic Arabidopsis plants overexpressing AtTSPO were more sensitive to ABA-induced growth inhibition, indicating that constitutive expression of AtTSPO may enhance ABA sensitivity. AtTSPO is rapidly downregulated during seeds imbibition, and the ABA-dependent induction in plant is transient. Downregulation of AtTSPO seems to be boosted by aminolevulenic acid treatment. Taken together, these results suggest that AtTSPO is a highly regulated protein, induced by abiotic stress to modulate, at least in part, transient intracellular ABA-dependent stress perception and/or signalling

The AtProT family. Compatible solute transporters with similar substrate specificity but differential expression patterns

Proline transporters (ProTs) mediate transport of the compatible solutes Pro, glycine betaine, and the stress-induced compound gamma-aminobutyric acid. A new member of this gene family, AtProT3, was isolated from Arabidopsis (Arabidopsis thaliana), and its properties were compared to AtProT1 and AtProT2. Transient expression of fusions of AtProT and the green fluorescent protein in tobacco (Nicotiana tabacum) protoplasts revealed that all three AtProTs were localized at the plasma membrane. Expression in a yeast (Saccharomyces cerevisiae) mutant demonstrated that the affinity of all three AtProTs was highest for glycine betaine (K-m = 0.1-0.3 mM), lower for Pro (K-m = 0.4-1 mM), and lowest for gamma-aminobutyric acid (K-m = 4-5 mM). Relative quantification of the mRNA level using real-time PCR and analyses of transgenic plants expressing the beta-glucuronidase (uidA) gene under control of individual AtProT promoters showed that the expression pattern of AtProTs are complementary. AtProT1 expression was found in the phloem or phloem parenchyma cells throughout the whole plant, indicative of a role in long-distance transport of compatible solutes. beta-Glucuronidase activity under the control of the AtProT2 promoter was restricted to the epidermis and the cortex cells in roots, whereas in leaves, staining could be demonstrated only after wounding. In contrast, AtProT3 expression was restricted to the above-ground parts of the plant and could be localized to the epidermal cells in leaves. These results showed that, although intracellular localization, substrate specificity, and affinity are very similar, the transporters fulfill different roles in planta

Severe autoimmune hemolytic anemia in a liver transplanted child

AIHA can complicate solid organ and bone marrow transplantation early after transplant. We describe the first case report of a 16-month-old boy with mixed type warm-acting IgM and warm IgG autoantibodies AIHA, occurring eight months after liver transplantation. This case describes the complexity of this very rare form of AIHA. It also illustrates the efficacy of rituximab in this indication, as well as the transfusion support with extremely rare blood, along with the importance of international collaboration to provide it. In this report, the etiologies of HA occurring in post-transplant pediatric patients are reviewed and the different treatment strategies are discussed