The effect of exogenous factors on the polyenzymatic activity of RuBisCO and ATP synthase of chloroplasts from pea leaves

Aim. To isolate and purify protein complexes – ATP synthase and RuBisCO – from pea leaf chloroplasts and study the effect of a microbiological fertilizer “Extracon” and sulfonamide inhibitors acetazolamide and ethoxyzolamide on the enzymatic activity of these proteins.Materials and methods. Chloroplasts were isolated from the leaves of two-week-old pea sprouts, protein complexes of purified thylakoid membranes were solubilized with digitonin (10 mg of digitonin per 1 mg of protein), the protein concentration was determined according to Lowry. Native electrophoresis with displacement of the charge of the soluble protein fraction from the chloroplast stroma, as well as membrane proteins, was carried out in the modified system of Anderson et al., Kolisnichenko et al. A modified Lemmley system was applied to the protein electrophoresis in the polyacrylamide gel in the presence of sodium dodecyl sulfate. The methods of Alain and Hintsik, as well as Gomorrah were used to determine the ATPase activity in the polyacrylamide gel. Visualization of the carbonic anhydrase activity in the polyacrylamide gel was performed by the method of Edwards and Petton. Results and discussion. Using physicochemical methods of potentiometry, spectrophotometry the ATPase, carbonic anhydrase and esterase activities of the enzymes were studied. The results obtained indicate that specific carbonic anhydrase inhibitors (acetazolamide and ethoxyzolamide) also block the esterase and ATPase activity of the enzyme complexes. “Extracon” (a multifunctional microbiological preparation) almost 1.5 times increases the activity of the enzymes, showing a complex activating effect of the fertilizer on both light and dark reactions of photosynthesis.Conclusions. The method of identification and isolation of RuBisCO and ATP synthase on the basis of two-dimensional electrophoresis and electrophoretic elution has been proposed. It allows determining the presence of certain enzyme activity of complexes at first in SDS plates (express analysis) and further to study the effect of various factors of endogenous and exogenous origin on the enzymatic properties of electrophoretically pure enzymes. The use of two-dimensional electrophoresis as a tool for assessing the impact of various factors of endogenous and exogenous origin on the plant cell and the plant as a whole through constant monitoring of the work and activity of enzyme systems of the plant cell is promising.

Updating Social Theory: Redefinition of Modernization

The article considered a critical appraisal of the modernization theory in its mono-paradigm frames and offers a heterodox conceptual meaning of modernization. Obviously, the varieties of methodological ap- proaches to that important theoretical topic would have to be much more comprehensive than con- temporary interpretations of linear pattern mainstream theories propose. Rethinking the conceptual foun- dations of the existing interpretation of the very concept is the model of adaptive modernization. Protect- ing its own matrix core, the system carries out partial correction of specific parameters, in which there is a lag, to increase their own vitality. Constructive changes are intra-systemic and occur within the existing order, without destroying its foundations, main institutional structures, and preserve the generic socio- cultural genotype Modernization, as reception of foreign cultural innovations (technical and technological) with their appropriate adaptation to the endogenous conditions, is an adequate adaptive response of a so- cial system to external risks or exogenous origin impact.

Effect of 1-naphthylacetic and indol-3-acetics acid on the intensity of callusogenesis and organogenesis of Linum usitatissimum L. in vitro

Aim. Investigate the effect of auxins of exogenous origin in nutrient medium in vitro on the germination and organogenesis intensity in Linum usitatissimum L. convar. elongatum (‘Hlinum’ variety) at the constant concentration of 6-benzylaminopurine (BAP). Methods. Hypocotyl segments were cultured on Murashige and Skoog nutrient medium supplemented with sucrose (30 g/l) and phytohormones at various concentrations. Other conditions: photoperiod 16 hours, relative humidity 60–80%, air temperature 22–24°C. Results. Common flax has a great capacity to form callus and shoots under the effect of the following factors: 1) only auxins, 2) only cytokines, 3) combinations of auxins and cytokines. Somatic embryogenesis is also possible on a nonhormonal nutrient medium. Conclusions. For somatic embryogenesis in vitro, the optimal concentrations of BAP can be expressed as 1.0 ≤ BAP ≤ 1.75, the optimal concentrations of BAP for the medium supplemented with 1-naphthylacetic (NAA, 0.05 mg/l) 0.5 ≤ BAP ≤ 2.0, the optimal concentration of NAA for the medium supplemented with BAP (1.0 mg/l) 0.025 ≤ NAA ≤ 0.150, and the optimal concentrations of indol-3-acetics acid (IAA) for the medium supplemented with BAP (1.0 mg/l) 0.05 ≤ IAA ≤ 0.50. Keywords: Linum usitatissimum L., in vitro, phytohormones, callus, organogenesis.

The Replication Stress Response on a Narrow Path Between Genomic Instability and Inflammation

The genome of eukaryotic cells is particularly at risk during the S phase of the cell cycle, when megabases of chromosomal DNA are unwound to generate two identical copies of the genome. This daunting task is executed by thousands of micro-machines called replisomes, acting at fragile structures called replication forks. The correct execution of this replication program depends on the coordinated action of hundreds of different enzymes, from the licensing of replication origins to the termination of DNA replication. This review focuses on the mechanisms that ensure the completion of DNA replication under challenging conditions of endogenous or exogenous origin. It also covers new findings connecting the processing of stalled forks to the release of small DNA fragments into the cytoplasm, activating the cGAS-STING pathway. DNA damage and fork repair comes therefore at a price, which is the activation of an inflammatory response that has both positive and negative impacts on the fate of stressed cells. These new findings have broad implications for the etiology of interferonopathies and for cancer treatment.

The importance of comorbidity in the presence of low culture positivity in a education and research hospital in Istanbul

Aims: To assess the clinical outcomes of patients with endophthalmitis.We also aimed the effect of comorbidities on hospitalization time, treatment management and vision gain.Metods: This retrospective study includes 40 eyes of 40 patients.Endophthalmitis was divided into as exogenous and endogenous groups.We investigated that culture results, comorbidities, hospitalization times, treatment management and vision gain.Patients with diabetes mellitus(DM) and/or hypertension(HT) were placed under comorbidity group 1.Patients with chronic distant organ inflammation in addition to DM and/or HT were placed under comorbidity group 2.Results: Endophthalmitis were exogenous origin in 25 eyes, endogenous origin in 15 eyes.Culture positivity rate,pars plana vitrectomy(PPV) rate,Intravitreal injection(IVI) rate,rePPV rate,two IVIs rate,more than two IVIs rate in exogenous and endogenous groups were 16%, 20%, respectively(culture positivity); 56%, 86.7%, respectively(PPV); 44%, 13.3%, respectively(IVI); 4%, 20%, respectively(rePPV); 52%, 6.7%, respectively(two IVIs); 20%, 66.7%, respectively(more than two IVIs).In exogenous group, mean hospitalization time in comorbidity group 1 and comorbidity group 2 was 7.3 ± 2.5, 10.5 ± 2.8 days, respectively.Mean number of IVIs in comorbidity group 2 was 28% more than comorbidity group 1.In endogenous group, mean hospitalization time in comorbidity group 1 and comorbidity group 2 was 14.3 ± 10.1, 22.0 ± 6.79 days, respectively.Mean number of IVIs in comorbidity group 2 was 86% more than comorbidity group 1.Conclusions: Because our culture and antibiogram findings were low, we had to increase surgical procedures and repeat IVI.This study showed that patients with chronic distant organ inflammation in addition to DM and/or HT encountered increased hospitalization times and IVI requirements.

Osteogenic differentiation factors of multipotent mesenchymal stromal cells in the current understanding

Background: Molecular genetic mechanisms, signaling pathways, conditions, factors, and markers of the osteogenic differentiation of mesenchymal stem cells (MSCs) are being actively studied and are among the most studied areas in the field of cellular technology. This attention is largely due to the mounting contradictions in the seemingly classical knowledge and the constant updating of results in the analyzed areas. In this regard, we focus on the main classical concepts and some new factors and mechanisms that have a noticeable regulatory effect on the differentiation potential of postnatal MSCs. Results: This review considers the importance of the sources of MSCs for the realization of their differentiation potential; molecular genetic factors and signaling pathways of MSC differentiation; the role of inflammatory cytokines and chemokines in osteogenesis; biomechanical signals; and the effect of conformational changes in the cellular cytoskeleton on MSC differentiation. Conclusion: It is concluded that it is necessary to move from studies focused of the effects of local genes to those taking multiple measurements of the gene-regulatory profile and the biomolecules critical for the implementation of numerous, incompletely studied osteogenic factors of endogenous and exogenous origin. Among the cornerstones of future (epi)genetic studies, whether osteomodulatory effects are realized through specific signaling pathways and/or whether cross-signaling with known genes drives the osteogenic differentiation of MSCs remain to be determined.

The Aryl Hydrocarbon Receptor as a Modulator of Anti-viral Immunity

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor, which interacts with a wide range of organic molecules of endogenous and exogenous origin, including environmental pollutants, tryptophan metabolites, and microbial metabolites. The activation of AHR by these agonists drives its translocation into the nucleus where it controls the expression of a large number of target genes that include the AHR repressor (AHRR), detoxifying monooxygenases (CYP1A1 and CYP1B1), and cytokines. Recent advances reveal that AHR signaling modulates aspects of the intrinsic, innate and adaptive immune response to diverse microorganisms. This review will focus on the increasing evidence supporting a role for AHR as a modulator of the host response to viral infection.

Activation-induced cytidine deaminase is a possible regulator of cross-talk between oocytes and granulosa cells through GDF-9 and SCF feedback system

Activation-induced cytidine deaminase (AID, Aicda) is a master gene regulating class switching of immunoglobulin genes. In this study, we investigated the significance of AID expression in the ovary. Immunohistological study and RT-PCR showed that AID was expressed in murine granulosa cells and oocytes. However, using the Aicda-Cre/Rosa-tdRFP reporter mouse, its transcriptional history in oocytes was not detected, suggesting that AID mRNA in oocytes has an exogenous origin. Microarray and qPCR validation revealed that mRNA expressions of growth differentiation factor-9 (GDF-9) in oocytes and stem cell factor (SCF) in granulosa cells were significantly decreased in AID-knockout mice compared with wild-type mice. A 6-h incubation of primary granuloma cells markedly reduced AID expression, whereas it was maintained by recombinant GDF-9. In contrast, SCF expression was induced by more than threefold, whereas GDF-9 completely inhibited its increase. In the presence of GDF-9, knockdown of AID by siRNA further decreased SCF expression. However, in AID-suppressed granulosa cells and ovarian tissues of AID-knockout mice, there were no differences in the methylation of SCF and GDF-9. These findings suggest that AID is a novel candidate that regulates cross-talk between oocytes and granulosa cells through a GDF-9 and SCF feedback system, probably in a methylation-independent manner.

Virus-like insertions with sequence signatures similar to those of endogenous nonretroviral RNA viruses in the human genome

Understanding the genetics and taxonomy of ancient viruses will give us great insights into not only the origin and evolution of viruses but also how viral infections played roles in our evolution. Endogenous viruses are remnants of ancient viral infections and are thought to retain the genetic characteristics of viruses from ancient times. In this study, we used machine learning of endogenous RNA virus sequence signatures to identify viruses in the human genome that have not been detected or are already extinct. Here, we show that the k-mer occurrence of ancient RNA viral sequences remains similar to that of extant RNA viral sequences and can be differentiated from that of other human genome sequences. Furthermore, using this characteristic, we screened RNA viral insertions in the human reference genome and found virus-like insertions with phylogenetic and evolutionary features indicative of an exogenous origin but lacking homology to previously identified sequences. Our analysis indicates that animal genomes still contain unknown virus-derived sequences and provides a glimpse into the diversity of the ancient virosphere.

Regulation Mechanisms of Expression and Function of Organic Cation Transporter 1

The organic cation transporter 1 (OCT1) belongs together with OCT2 and OCT3 to the solute carrier family 22 (SLC22). OCTs are involved in the movement of organic cations through the plasma membrane. In humans, OCT1 is mainly expressed in the sinusoidal membrane of hepatocytes, while in rodents, OCT1 is strongly represented also in the basolateral membrane of renal proximal tubule cells. Considering that organic cations of endogenous origin are important neurotransmitters and that those of exogenous origin are important drugs, these transporters have significant physiological and pharmacological implications. Because of the high expression of OCTs in excretory organs, their activity has the potential to significantly impact not only local but also systemic concentration of their substrates. Even though many aspects governing OCT function, interaction with substrates, and pharmacological role have been extensively investigated, less is known about regulation of OCTs. Possible mechanisms of regulation include genetic and epigenetic modifications, rapid regulation processes induced by kinases, regulation caused by protein–protein interaction, and long-term regulation induced by specific metabolic and pathological situations. In this mini-review, the known regulatory processes of OCT1 expression and function obtained from in vitro and in vivo studies are summarized. Further research should be addressed to integrate this knowledge to known aspects of OCT1 physiology and pharmacology.