T-LAK cell-originated protein kinase (TOPK) phosphorylation of MKP1 protein prevents solar ultraviolet light-induced inflammation through inhibition of the p38 protein signaling pathway

Solar UV radiation is a major environmental factor that causes DNA damage, inflammation, and even skin cancer. T-LAK cell-originated protein kinase (TOPK) is expressed widely in both normal and cancer cells and functions to inhibit apoptosis and promote carcinogenesis. However, its function in inflammation is not known. The p38 MAPK signaling pathway plays an important role in solar UV light-induced inflammation. In this study, we found that TOPK negatively regulated the activity of p38α by phosphorylating the p38α-specific phosphatase MKP1 and enhancing the stability of MKP1. Notably, the absence of TOPK in mice resulted in a striking increase in skin inflammation. Therefore, we conclude that TOPK has a protective function in solar UV light-induced inflammation.     

Synthesis of 3β-hydroxy-androsta-5,7-dien-17-one from 3β-hydroxyandrost-5-en-17-one via microbial 7α-hydroxylation

The synthesis of 3β-hydroxy-androsta-5,7-dien-17-one from 3β-hydroxy-androst-5-en-17-one (dehydroepiandrosterone, DHEA) via microbial 7α-hydroxylation has been accomplished. At the first stage, 3β,7α-dihydroxy-androst-5-en-17-one was obtained in high yield (71.2%) using a strain of Gibberella zeae VKM F-2600, which was first applied for DHEA conversion. The further route included the substitution of 7α-hydroxyl group with chlorine followed by a dehydrochlorination stage, and required minimal purifications of the intermediate products. The steroids obtained at every step were characterized by TLC_,¹H NMR, MS, UV- and IR-spectrometry.The combination of microbial and chemical steps ensured 54.6% yield of the target 3β-hydroxy-androsta-5,7-dien-17-one from DHEA and can be applied for obtaining novel vitamin D derivatives.     

Lamellipodial versus filopodial mode of the actin nanomachinery: pivotal role of the filament barbed end

Understanding how a particular cell type expresses the lamellipodial or filopodial form of the actin machinery is essential to understanding a cell's functional interactions. To determine how a cell "chooses" among these alternative modes of "molecular hardware," we tested the role of key proteins that affect actin filament barbed ends. Depletion of capping protein (CP) by short hairpin RNA (shRNA) caused loss of lamellipodia and explosive formation of filopodia. The knockdown phenotype was rescued by a CP mutant refractory to shRNA, but not by another barbed-end capper, gelsolin, demonstrating that the phenotype was specific for CP. In Ena/VASP deficient cells, CP depletion resulted in ruffling instead of filopodia. We propose a model for selection of lamellipodial versus filopodial organization in which CP is a negative regulator of filopodia formation and Ena/VASP has recruiting/activating functions downstream of actin filament elongation in addition to its previously suggested anticapping and antibranching activities.     

Novel hydrolase diversity retrieved from a metagenome library of bovine rumen microflora

A metagenome expression library of bulk DNA extracted from the rumen content of a dairy cow was established in a phage lambda vector and activity-based screening employed to explore the functional diversity of the microbial flora. Twenty-two clones specifying distinct hydrolytic activities (12 esterases, nine endo-beta-1,4-glucanases and one cyclodextrinase) were identified in the library and characterized. Sequence analysis of the retrieved enzymes revealed that eight (36%) were entirely new and formed deep-branched phylogenetic lineages with no close relatives among known ester- and glycosyl-hydrolases. Bioinformatic analyses of the hydrolase gene sequences, and the sequences and contexts of neighbouring genes, suggested tentative phylogenetic assignments of the rumen organisms producing the retrieved enzymes. The phylogenetic novelty of the hydrolases suggests that some of them may have potential for new applications in biocatalysis.     

Role of Single Nucleotide Polymorphism L55M in the Paraoxonase 1 Gene as a Risk and Prognostic Factor in Acute Coronary Syndrome

The aim of the current study is to explore the possible role of L55M, (rs 854560, 163T > A) SNP as a predisposing factor for acute coronary syndrome (ACS) and to assess its potency as a prognostic biomarker for short (1 year) survival and for median (5 years) and 9-year long patients’ outcome. Methods: The current work is a prospective case-control study with 77 patients with acute coronary syndrome (53 with ST-elevation myocardial infarction, STEMI, 14 with non-ST-elevation myocardial infarction, NSTEMI and 10 with unstable angina, UA) and 122 control individuals. Patients were followed-up for 9 years. The genotyping for PON1 L55M SNP was carried on by PCR-RFLP method. Results: The results of the genotyping for PON1 L55M SNP showed a statistically significant difference (p = 0.023) between the controls and the whole group of patients with acute coronary syndrome, as the individuals with genotype with at least one variant M allele had about 2.5-fold higher risk for developing ACS than those which are homozygous of the wild-type L allele (LL genotype). In patients with variant M allele genotypes (LM + MM) which suffer from non-ST-segment elevation ACS (NSTEACS, i.e., UA or NSTEMI), the serum levels of total cholesterol (TC) and triacylglycerols (TAG) are significantly higher than in NSTEACS patients with LL genotype (p = 0.022 for TC and p = 0.015 for TAG). There was no significant difference in the survival rate at the 1st, 5th and 9th year of follow-up between ACS patients with different genotypes, although it is worth to note that in the subgroup of NSTEACS, all patients (n = 13) with variant M allele genotypes (LM + MM) were alive at the end of the first year, while 2 of the patients with LL genotype (18.2%) were dead. Conclusions: The results of our current study suggest that the variant M allele and the M allele genotypes (LM + MM) of the PON1 L55M polymorphism are risk factors for acute coronary syndrome, especially for patients with STEMI, but do not support the possible effect of this polymorphism on the clinical progression and outcome of the patients with ACS either in short or long follow-up periods.     

Dietary Effects on Cuticular Hydrocarbons and Sexual Attractiveness in Drosophila

Dietary composition is known to have profound effects on many aspects of animal physiology, including lifespan, general health, and reproductive potential. We have previously shown that aging and insulin signaling significantly influence the composition and sexual attractiveness of Drosophila melanogaster female cuticular hydrocarbons (CHCs), some of which are known to be sex pheromones. Because diet is intimately linked to aging and to the activity of nutrient-sensing pathways, we asked how diet affects female CHCs and attractiveness. Here we report consistent and significant effects of diet composition on female CHC profiles across ages, with dietary yeast and sugar driving CHC changes in opposite directions. Surprisingly, however, we found no evidence that these changes affect female attractiveness. Multivariate comparisons among responses of CHC profiles to diet, aging, and insulin signaling suggest that diet may alter the levels of some CHCs in a way that results in profiles that are more attractive while simultaneously altering other CHCs in a way that makes them less attractive. For example, changes in short-chain CHCs induced by a high-yeast diet phenocopy changes caused by aging and by decreased insulin signaling, both of which result in less attractive females. On the other hand, changes in long-chain CHCs in response to the same diet result in levels that are comparable to those observed in attractive young females and females with increased insulin signaling. The effects of a high-sugar diet tend in the opposite direction, as levels of short-chain CHCs resemble those in attractive females with increased insulin signaling and changes in long-chain CHCs are similar to those caused by decreased insulin signaling. Together, these data suggest that diet-dependent changes in female CHCs may be sending conflicting messages to males.     

Ecological and Biochemical Evaluation of the Environment of Modern Foraminifers of the White Sea

Current ecological conditions in the regions of Bol'shoi Keretskii raid and Glubokaya Salma (Kandalaksha Bay, White Sea) were evaluated on the basis of structural and dynamic indices of the upper sediments in the context of specific composition of the benthic foraminiferal community. The distribution of the main species of living foraminifers was determined for the shallow and deep-sea groups. The relationship between populations of the most abundant species of living benthic foraminifers and hydrolytic enzyme activities providing for destruction of bottom organic matter at biochemical rates has been revealed.     

The changes in chromosome 6 spatial organization during chromatin polytenization in the Calliphora erythrocephala Mg. (Diptera: Calliphoridae) nurse cells

Localization of Calliphora erythrocephala chromosome 6 in a 3D nuclear space at different stages of nurse cell chromatin polytenization was analyzed by fluorescence in situ hybridization and 3D microscopy. The obtained results suggest a large-scale chromatin relocation in the C. erythrocephala nurse cell nuclei, which is accompanied by a change in the chromosome territory of chromosome 6 associated with the change in expression activity of the nucleus and formation of reticular chromatin structure. It was revealed that the relocation of chromosome 6 (nucleolus organizer chromosome) is accompanied by fragmentation of the single large nucleolus into micronucleoli, which are spread over the entire nuclear space being associated with their nucleolar organizer regions. Presumably, the chromosome 6 material during transition to a highly polytenized structure is redistributed in the nucleus so that the inactive pericentromeric regions are displaced to the nuclear periphery, while the chromosome regions carrying rDNA sequences loop out beyond the chromosome territory. Being dispersed over the entire nuclear space, rDNA sequences are likely to be amplified, thereby providing numerous small signals from the chromosome 6-specific DNA probe. Micronucleoli are formed around the actively transcribed nucleolar organizer regions.     

Genetic Regulatory Mechanisms of Evolution and Embryogenesis in a Distorting Mirror of Carcinogenesis

The article is an attempt to provide an overview of the relationships between the regulatory genetic mechanisms of three fundamental processes of biology, i.e., development, evolution, and cancer. The problems of the evolutionary inevitability of the onset of cancer, the evolutionarily developed systems for protecting the body against tumors, and the general systems of regulation used in evolution, development, and cancer are considered.     

Cell cycle–related metabolism and mitochondrial dynamics in a replication-competent pancreatic beta-cell line

Cell replication is a fundamental attribute of growth and repair in multicellular organisms. Pancreatic beta-cells in adults rarely enter cell cycle, hindering the capacity for regeneration in diabetes. Efforts to drive beta-cells into cell cycle have so far largely focused on regulatory molecules such as cyclins and cyclin-dependent kinases (CDKs). Investigations in cancer biology have uncovered that adaptive changes in metabolism, the mitochondrial network, and cellular Ca²⁺ are critical for permitting cells to progress through the cell cycle. Here, we investigated these parameters in the replication-competent beta-cell line INS 832/13. Cell cycle synchronization of this line permitted evaluation of cell metabolism, mitochondrial network, and cellular Ca²⁺ compartmentalization at key cell cycle stages. The mitochondrial network is interconnected and filamentous at G1/S but fragments during the S and G2/M phases, presumably to permit sorting to daughter cells. Pyruvate anaplerosis peaks at G1/S, consistent with generation of biomass for daughter cells, whereas mitochondrial Ca²⁺ and respiration increase during S and G2/M, consistent with increased energy requirements for DNA and lipid synthesis. This synchronization approach may be of value to investigators performing live cell imaging of Ca²⁺ or mitochondrial dynamics commonly undertaken in INS cell lines because without synchrony widely disparate data from cell to cell would be expected depending on position within cell cycle. Our findings also offer insight into why replicating beta-cells are relatively nonfunctional secreting insulin in response to glucose. They also provide guidance on metabolic requirements of beta-cells for the transition through the cell cycle that may complement the efforts currently restricted to manipulating cell cycle to drive beta-cells through cell cycle.