Doklady Biological Sciences最新文献

Microplastics (MPs) were for the first time isolated and partly identified from the contents of the gastrointestinal (GI) tract in striped field mice (Apodemus agrarius Pallas, 1771) from two Moscow parks, Neskuchny Garden (n = 5) and Terletsky Park (n = 1). MPs were found in the GI tracts of all mice examined. Small multicolored threads dominated in samples. The chemical composition of the longest thread (>4 mm) was analyzed using a Foton-Bio Raman microscope (Russia). A toxic copolymer of vinylidene chloride and acrylonitrile was identified in the composition (72.4% match). Artificial coverings in the park or films were presumably its source. The findings will contribute to the development of measures to control MP pollution in urban ecosystems and are important for assessing the risk to other vertebrates, including humans.

Current data indicate that the Hox gene expression pattern differs between regular and irregular sea urchins. Expression of most genes of the Hox cluster is not activated until the pluteus forms, and only Hox7, 11/13b, and 11/13c are expressed at the blastula stage in two Regularia species examined previously, Strongylocentrotus purpuratus and St. intermedius. In contrast, in Peronella japonica, the only species studied in Irregularia, Hox7, 9/10, 11/13b, and 11/13c are expressed at the blastula and gastrula stages; Hox1, 7, 8, 9/10, 11/13a, and 11/13b are expressed at the prism stage; and most genes of the Hox cluster are activated at the pluteus stage. The irregular sea urchin Scaphechinus mirabilis was examined. Almost all of its Hox genes were silent at early stages. SmHox11/13b was an exception and was expressed at the gastrula stage. Most Hox genes were activated only at the pluteus stage. Thus, the expression pattern of the Hox cluster in Sc. mirabilis is similar to that of the regular sea urchins St. purpuratus and St. intermedius and differs from that of the other irregular sea urchin P. japonica.

Gene expression levels of myogenic regulatory factors (MRFs) (myf5, myod2, and myog), myostatin (mstn1a and mstn1b), and the muscle protein myosin (myhc) in muscles were studied in the rainbow trout Oncorhynchus mykiss Walb. Study fish of three size groups (SGs) were fed with two commercial feeds differing in compositions. Expression levels of myhc, myf5, myog, and mstn1a in muscles were found to differ depending on the feed, especially in smaller fish (<1000 g). The finding suggests that the feed composition, including the quantitative ratio of ingredients and the sources of proteins, fats, and carbohydrates in the feed, affects the muscle growth regulation in early trout growth and development. The results complement the literature data on features of the regulation of myogenesis in response to external factors.

Total protease activity and activities of protease subclasses in the small intestine were assayed in herring gull (Larus argentatus (Pontoppidan, 1763)) chicks infested by the cestodes Tetrabothrius erostris (Loennberg, 1889) (Cestoda: Tetrabothriidae), Microsomacanthus ductilus (Linton, 1927) (Cestoda: Hymenolepididae), Wardium cirrosa (Krabbe, 1869) (Cestoda: Aploparaksidae), Arctotaenia tetrabothrioides (Loennberg, 1890), and Alcataenia larina (Krabbe, 1869) (Cestoda: Dilepididae). Serine protease activity was found to decrease in small intestine sites with the highest cestode abundance (M. ductilus in the proximal segment; W. cirrosa in the distal segment; and Ar. tetrabothrioides, T. erostris, and Al. larina in the medial segment). Cysteine protease activity increased in sites of M. ductilus, W. cirrosa, and Al. larina location. Protease absorption on the tegument surface was observed in all of the cestodes under study, and serine proteases accounted for a major part of the absorbed enzymes. Homogenates of W. cirrosa, M. ductilus, Ar. tetrabothrioides, T. erostris, and Al. larina were shown to inhibit activities of host proteases and commercial trypsin.

Using genome editing, we created a homozygous α-(1,6)-fucosyltransferase (FUT8^-/^-) knockout in apoptosis-resistant CHO 4BGD cells, yielding the new 4BGD-F cell line. Combining CRISPR/Cas9 with paired gRNAs and non-specific puromycin selection yielded a cell population with an exceptionally high FUT8 knockout frequency, obviating the need for metabolic enrichment with lentil lectin (Lens culinaris agglutinin, LCA). Despite impaired clonogenicity of the knockout cells, we successfully isolated multiple clonal cell lines harboring extensive biallelic FUT8 deletions. Isolated clones with biallelic deletions retained key parental line characteristics: viability >90% in 17-day fed-batch cultures at high densities (>15 × 10⁶ cells/mL), and rapid selectability using both dihydrofolate reductase and glutamine synthetase systems. Mass spectrometric analysis of the test protein GLP1-Fc secreted by 4BGD-F cells confirmed the absence of N-glycan fucosylation. The CHO 4BGD-F cell line provides a valuable platform for producing afucosylated antibodies with enhanced antibody-dependent cellular cytotoxicity.

The features of Myxobolus pronini location in Prussian carps (Carassius auratus gibelio) were described and the relationships in the parasite-host system analyzed. Large spore masses surrounded by a connective tissue capsule were found in the body cavity. The development of vegetative M. pronini forms was observed to start in exocrine tissue of the carp pancreas.

Exocytosis and endocytosis of synaptic vesicles were studied in experiments with motor nerve endings of diaphragm neuromuscular preparations isolated from transgenic mice with a model of amyotrophic lateral sclerosis (ALS); treatment simulated antioxidant (edaravone) and gene-cell (umbilical cord blood mononuclear cells (UCB-MNCs) producing VEGF, GDNF, and NCAM) therapies. None of the treatments was found to significantly change the FM 1-43 fluorescent dye loading due to synaptic vesicle endocytosis. Gene-cell therapy increased the rate of dye unloading due to synaptic vesicle exocytosis, while antioxidant therapy did not change the FM 1-43 unloading rate. Based on the findings, gene-cell therapy was assumed to facilitate synaptic vesicle transport to release sites upon high-frequency stimulation in motor nerve endings of transgenic mice.

Stress at early stages of development is known to affect a lot of physiological traits in mammals, but much less is known concerning its effect on physiology of Holometabola insects. In this study, we report for the first time that heat stress experienced by 3rd instar larvae of Drosophila melanogaster (32°C, 48 h) results in a decrease in egg-to-imago development rate. Such stress also results in a drop in fertility at the beginning of the reproduction period (the first 48 h after the oviposition onset). The data obtained are indicative of the transition of physiological changes caused by early stress through metamorphosis. Thus, the results of our study support the idea of metamorphosis not erasing the influence of factors that affected the insect before its start universally among Holometabola.

The hemocyte transcriptome was for the first time obtained and analyzed in uninfected Planorbarius corneus snails and snails naturally infected with Bilharziella polonica parthenites (Schistosomatidae). Transcripts encoding all groups of immune factors previously described in other gastropods were found in assemblies. Pathogen recognition molecules were the most diverse group of transcripts encoding immunity factors. Toll-like receptors (TLRs) of 11 types were identified. The TLR set did not differ between infected and uninfected snails. The data expand the knowledge of snail immune responses to trematode invasion and make it possible to consider P. corneus as a new model for studying mollusk immune reactions.

A new fossil avifauna, dated to an unspecified Upper Pleistocene, is reported from the Khondu locality discovered recently in central Yakutia. Based on materials collected in 2023 and 2024, at least 25 bird taxa from the families Phasianidae (Lagopus lagopus), Anatidae (ten species), Podicipedidae (two species), Scolopacidae (five species), Accipitridae (Buteo sp. and Circus sp.), Alaudidae (Eremophila alpestris), and Turdidae (one species) were identified. The fauna is the northernmost representative Pleistocene fossil bird fauna in Eastern Siberia and the second one from Yakutia. The avifauna of Khondu is generally similar to that from Upper Pleistocene layers of the Dyuktai Cave (southeastern Yakutia), but differs in the presence of several species. In particular, the common pochard Aythya ferina was found, indicating more favorable environmental conditions during the formation of the taphocenosis. The presence of arboreal vegetation is inferred from the finds of goldeneye Bucephala clangula remains, including those of subadult individuals. Of particular interest are the finds of two wader species, the ringed plover Charadrius hiaticula and the Far Eastern curlew Numenius madagascariensis. This is the first find of the ringed plover in the Pleistocene of Asia, and the first find of the Far Eastern curlew in the fossil record.