Doklady Rossijskoj akademii nauk. Nauki o žizni

Heterodimeric phospholipase A2 HDP-1 from the venom of Nikolsky viper consists of two non-covalently bound subunits – HDP-1P and HDP-1In, the first of which exhibits lipolytic activity, while the second does not. The subunits have close molecular masses and similar amino acid sequences. Administration of HDP-1 and HDP-1P to anesthetized rats is accompanied by prolonged hypotensive effects, the intensity of which depends on the dose. With the administration of HDP-1P, the effect develops more slowly than in the case of HDP-1 containing both subunits, while individual HDP-1In does not affect hemodynamic parameters. It was found using electrocardiography that HDP-1 and HDP-1P affect the functioning of the rat heart, causing arrhythmia, which may indicate their ability to affect the innervation of the heart. The administration of HDP-1 and its subunits also leads to changes in biochemical blood parameters, indicating their damaging effect on cells and internal organs.

The composition and content of fatty acids of the sand lizard (Lacerta agilis) and its potential food objects in the shore and steppe biotopes were studied. For the first time, it was established that the content of long-chain omega-3 polyunsaturated fatty acids, primarily eicosapentaenoic acid (EPA), significantly increases in the tissues of lizards from a shore biotope during the period of emergence of amphibious insects from the nearby salt Lake Shira. Among all the food sources of lizards, the highest EPA content was found in chironomids imago. The content of docosahexaenoic acid (DHA) in the muscles of the lizards was also high, although this acid was not detected in the invertebrates that the lizards consumed. In this regard, it has been suggested that the sand lizard is able to biosynthesize DHA from biochemical precursors contained in food.

The method of intravital bioimaging based on luminescence occupies an important place in the development and testing of antitumor drugs on model animals and is an essential part of preclinical studies. Bioimaging based on luminescent systems, compared with fluorescent bioimaging, provides a high signal-to-noise ratio, which justifies the development of cell lines, that stably express luciferase genes for subsequent use in model animals. The work describes the creation of a stable cell line SKOV3.ip1-NanoLuc constitutively expressing the NanoLuc luciferase gene. The developed cell line was shown to be effective for intravital luminescence bioimaging of immunodeficient animals with deep-seated intraperitoneal tumors, which can be considered as a model of late-stage ovarian cancer.

Bioinformatic methods have been used to predict a new subclass of proteins among plant phosphotransmitters involved in the signaling system of multistep phosphorelay. In contrast to the canonical soluble nucleocytosolic forms, the found phosphotransmitter sequences, belonging to a wide range of plant taxa, potentially contain transmembrane domains. This suggests localization of such proteins on cell membranes and, therefore, a different function in signaling than that of canonical phosphotransmitters. We tested the functionality of the transmembrane domain of the phosphotransmitter using the protein of the tea plant Camellia sinensis. Membrane localization of the transiently expressed recombinant phosphotransmitter with this domain was confirmed by microscopy and immunoblotting. Thus, for the first time, experimental evidence was obtained for the existence of membrane-bound plant phosphotransmitters with as yet unknown functions. These data suggest the presence of a non-canonical membrane branch of signal transduction in the multistage phosphotransfer system in plants.

A parasitological analysis of 24 dog coprolite samples, 1 cultural deposit, and 4 dung samples obtained during excavations of the Mangazeya settlement (66°42’ N, 82°16’ E), the first Russian city of the 17th century (late Holocene) in the north of Western Siberia was performed. Helminth eggs were found in 26 (89.7%) samples. Echinochasmus sp. eggs were found in 48.3% of the samples: in the cultural deposit, in 2 dung samples, and in 11 dog coprolite ones. This genus is currently absent in the helminth fauna of the region. It could have entered the region with infected dogs, pigs, and humans who arrived to the region from European Russia. The introduction of the helminth did not lead to the formation of a new stable natural focus of echinochasmosis, which is associated with the unfavorable climatic conditions of the region.