INFLUENCE OF TEMPERATURE CONDITIONS ON THE ACCUMULATION OF PRIMARY AND SECONDARY METABOLITES BY LICHENS FLAVOCETRARIA CUCULLATA AND CETRARIA LAEVIGATA

The study of the effect of temperature on the accumulation of primary and secondary metabolites by lichens Flavocetraria cucullata (Bellardi) Kärnefelt & Thell and Cetraria laevigata Rass was carried out. Lichen samples were taken out from under the snow (-20 °C) together with the soil substrate and transferred to the climatic chamber. Then the temperature in the climatic chamber was sequentially increased to +10 and +20 °C. The lichen exposure was carried out for 30 days for each temperature regime. The analysis of primary metabolites was performed by gas chromatography-mass spectrometry. It was shown that in lichens F. cucullata and C. laevigata at temperatures of +10 and +20 °C, an increase in the content of mannitol, ribitol, sucrose, and hydroxyproline was observed, as well as a decrease in the content of unsaturated fatty acids as compared to the initial samples. At the same time, the content of glycerol and arabitol in the thalli of the initial lichens (-20 °C) was higher than after exposure at +10 and +20 °C, which, apparently, is associated with the cryoprotective properties of these compounds. The content of secondary metabolites in lichens was determined by high performance liquid chromatography. It was shown that the content of usnic, allo-protolichesterinic, and protolichesterinic acids in F. cucullata increased after exposure in a climatic chamber, which may be associated with a general activation of metabolic processes with an increase in temperature. At the same time, the content of fumarprotocetraric acid in C. laevigata lichens decreased at temperatures of +10 and +20 °C compared to the initial samples, which may be associated with its protective properties under the action of low-temperature stress.

A combinatorial cis-regulatory logic restricts color-sensing Rhodopsins to specific photoreceptor subsets in Drosophila

Color vision in Drosophila melanogaster is based on the expression of five different color-sensing Rhodopsin proteins in distinct subtypes of photoreceptor neurons. Promoter regions of less than 300 base pairs are sufficient to reproduce the unique, photoreceptor subtype-specific rhodopsin expression patterns. The underlying cis-regulatory logic remains poorly understood, but it has been proposed that the rhodopsin promoters have a bipartite structure: the distal promoter region directs the highly restricted expression in a specific photoreceptor subtype, while the proximal core promoter region provides general activation in all photoreceptors. Here, we investigate whether the rhodopsin promoters exhibit a strict specialization of their distal (subtype specificity) and proximal (general activation) promoter regions, or if both promoter regions contribute to generating the photoreceptor subtype-specific expression pattern. To distinguish between these two models, we analyze the expression patterns of a set of hybrid promoters that combine the distal promoter region of one rhodopsin with the proximal core promoter region of another rhodopsin. We find that the function of the proximal core promoter regions extends beyond providing general activation: these regions play a previously underappreciated role in generating the non-overlapping expression patterns of the different rhodopsins. Therefore, cis-regulatory motifs in both the distal and the proximal core promoter regions recruit transcription factors that generate the unique rhodopsin patterns in a combinatorial manner. We compare this combinatorial regulatory logic to the regulatory logic of olfactory receptor genes and discuss potential implications for the evolution of rhodopsins.

AKT in Bone Metastasis of Solid Tumors: A Comprehensive Review

Solid tumors, such as breast cancer and prostate cancer, often form bone metastases in the course of the disease. Patients with bone metastases frequently develop complications, such as pathological fractures or hypercalcemia and exhibit a reduced life expectancy. Thus, it is of vital importance to improve the treatment of bone metastases. A possible approach is to target signaling pathways, such as the PI3K/AKT pathway, which is frequently dysregulated in solid tumors. Therefore, we sought to review the role of the serine/threonine kinase AKT in bone metastasis. In general, activation of AKT signaling was shown to be associated with the formation of bone metastases from solid tumors. More precisely, AKT gets activated in tumor cells by a plethora of bone-derived growth factors and cytokines. Subsequently, AKT promotes the bone-metastatic capacities of tumor cells through distinct signaling pathways and secretion of bone cell-stimulating factors. Within the crosstalk between tumor and bone cells, also known as the vicious cycle, the stimulation of osteoblasts and osteoclasts also causes activation of AKT in these cells. As a consequence, bone metastasis is reduced after experimental inhibition of AKT. In summary, AKT signaling could be a promising therapeutical approach for patients with bone metastases of solid tumors.

Profiling Complement System Components in Primary CNS Vasculitis

Complement activation has been implicated in the pathogenesis of many vasculitic syndromes such as anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides. Using an array-based multiplex system, we simultaneously quantified serum and CSF levels of activated and regulatory complement system proteins in patients with primary CNS vasculitis (PACNS; n = 20) compared to patients with non-inflammatory conditions (n = 16). Compared to non-inflammatory controls, levels of C3a, C5a, and SC5b-9, indicative for general activation of the complement system, of C4a, specific for the activation of the classical pathway, Ba and Bb, reflective for alternative complement activation as well as concentrations of complement-inhibitory proteins factor H and factor I were unchanged in patients with PACNS. Our study does not support the hypothesis that complement activation is systemically increased in patients with PACNS.

Serca2a-Phospholamban Interaction Monitored by an Interposed Circularly Permutated Green Fluorescent Protein

Background: The interaction of phospholamban (PLB) and the sarcoplasmic reticulum Ca2+-ATPase (Serca2a) is a key regulator of cardiac contractility and a therapeutic target in heart failure (HF). PLB mediated increases in Serca2a activity improve cardiac function and HF. Clinically this mechanism can only be exploited by a general activation of the proteinkinase A (PKA) which is associated with side effects and adverse clinical outcomes. A selective interference of the PLB-Serca2a interaction is desirable but will require novel tools that allow for an integrated assessment of this interaction under both physiological and pathophysiological conditions. Methods: A circularly permutated green fluorescent protein (cpGFP) was interposed between Serca2a and PLB to result into a single Serca2a-cpGFP-PLB recombinant protein (SGP). Expression, phosphorylation, fluorescence and function of SGP were evaluated. Results: Expression of SGP-cDNA results in a functional recombinant protein at the predicted molecular weight. The PLB domain of SGP retains its ability to polymerize and can be phosphorylated by PKA activation. This increases the fluorescent yield of SGP by between 10% to 165% depending on cell line and conditions. Summary: A single recombinant fusion protein that combines Serca2a, a circularly permutated green fluorescent protein and PLB can be expressed in cells and can be phosphorylated at the PLB domain which markedly increases the fluorescence yield. SGP is a novel cellular Serca2a-PLB interaction monitor.

Trends in the development of volunteering in modern Russia

The article examines the main trends in the development of volunteering in Russia at the present stage. Attention is drawn to the general activation in the volunteer movement of schoolchildren, students, as well as older people.