α4β1 integrin and erythropoietin mediate temporally distinct steps in erythropoiesis: integrins in red cell development

Erythropoietin (Epo) is essential for the terminal proliferation and differentiation of erythroid progenitor cells. Fibronectin is an important part of the erythroid niche, but its precise role in erythropoiesis is unknown. By culturing fetal liver erythroid progenitors, we show that fibronectin and Epo regulate erythroid proliferation in temporally distinct steps: an early Epo-dependent phase is followed by a fibronectin-dependent phase. In each phase, Epo and fibronectin promote expansion by preventing apoptosis partly through bcl-xL. We show that α4, α5, and β1 are the principal integrins expressed on erythroid progenitors; their down-regulation during erythropoiesis parallels the loss of cell adhesion to fibronectin. Culturing erythroid progenitors on recombinant fibronectin fragments revealed that only substrates that engage α4β1-integrin support normal proliferation. Collectively, these data suggest a two-phase model for growth factor and extracellular matrix regulation of erythropoiesis, with an early Epo-dependent, integrin-independent phase followed by an Epo-independent, α4β1-integrin–dependent phase

Experimental annotation of post-translational features and translated coding regions in the pathogen Salmonella Typhimurium

<p>Abstract</p> <p>Background</p> <p>Complete and accurate genome annotation is crucial for comprehensive and systematic studies of biological systems. However, determining protein-coding genes for most new genomes is almost completely performed by inference using computational predictions with significant documented error rates (> 15%). Furthermore, gene prediction programs provide no information on biologically important post-translational processing events critical for protein function.</p> <p>Results</p> <p>We experimentally annotated the bacterial pathogen <it>Salmonella </it>Typhimurium 14028, using "shotgun" proteomics to accurately uncover the translational landscape and post-translational features. The data provide protein-level experimental validation for approximately half of the predicted protein-coding genes in <it>Salmonella </it>and suggest revisions to several genes that appear to have incorrectly assigned translational start sites, including a potential novel alternate start codon. Additionally, we uncovered 12 non-annotated genes missed by gene prediction programs, as well as evidence suggesting a role for one of these novel ORFs in <it>Salmonella </it>pathogenesis. We also characterized post-translational features in the <it>Salmonella </it>genome, including chemical modifications and proteolytic cleavages. We find that bacteria have a much larger and more complex repertoire of chemical modifications than previously thought including several novel modifications. Our <it>in vivo </it>proteolysis data identified more than 130 signal peptide and N-terminal methionine cleavage events critical for protein function.</p> <p>Conclusion</p> <p>This work highlights several ways in which application of proteomics data can improve the quality of genome annotations to facilitate novel biological insights and provides a comprehensive proteome map of <it>Salmonella </it>as a resource for systems analysis.</p

Relationship between salt tolerance related physiological traits and protein markers in soybean cultivars (Glycine max L.)

This study was conducted to evaluate the salinity tolerance in seedling stage of soybean (Glycine max L.). Factorial experiment was done based on randomized complete block design with three replicates. 17 soybean genotypes were used in three salinity stress levels (consisting of control, 75 mM and 150 mM NaCl stress). The experiment was carried out in a greenhouse condition and proline, sodium, potassium, and chlorophyll a, chlorophyll b, chlorophyll a/b and total chlorophyll content were examined. To create salinity stress, NaCl was used in the experiment. The results revealed that different salinity stress had significant effects on all traits except for chlorophyll b and chlorophyll a/b. The cluster analysis in the control and at 75 and 150 mM salinity levels classified genotypes into two, two and three groups respectively. In each condition, the dpx and clean genotypes were placed in a group which the average traits were higher than the other genotypes. This can be generalized to the conditions of control as well as 75 and 150 mM salinity stress. Regression analysis showed possible informative loci encoding protein markers that was probable potential for selection strategies for salt weather proved by complementary tests

Efficacy and safety of resveratrol, an oral hemoglobin F-augmenting agent, in patients with beta-thalassemia intermedia

Recently, resveratrol showed induction of γ-globin mRNA synthesis in human erythroid precursors and reducing oxidative stress in red cells of thalassemia patients in many in vitro studies. We aimed to investigate the efficacy and safety of resveratrol, for the first time, in non-transfusion-dependent beta-thalassemia intermedia (B-TI) in Southern Iran. In this double-blind randomized clinical trial, 54 patients with B-TI were investigated during 6 months between October 2016 and March 2017. Patients were randomly allocated into three groups by simple randomization method. Group 1 (hydroxyurea (HU) and placebo, 18 patients), group 2 (resveratrol/piperine and placebo, 16 patients), and group 3(HU and resveratrol/piperine, 20 patients). Primary end point was considered as change in hemoglobin (Hb) levels and need for blood transfusion. Drug safety was considered as a secondary end point. Mean age of the patients was 28.2 ± 5.6 (18�42) years. Response rate was not significantly different among the three groups (P > 0.05). Higher percentages of adverse events were detected in groups 2 (31.3) and 3 (25) compared to group 1 (5.6). However, the difference was not statistically significant (P > 0.05). All reported adverse events were gastrointestinal symptoms. Resveratrol showed a similar efficacy with HU in the small population of non-transfusion B-TI patients during a 6-month follow-up. Complications, mostly gastrointestinal, were observed more frequently in resveratrol groups compared to the HU group. Although it was not statistically significant, more attention should be given to safety and efficacy of resveratrol as an oral HbF-augmenting agent. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature