Nuclear gene indicates coat-color polymorphism in mammoths

By amplifying the melanocortin type 1 receptor from the woolly mammoth, we can report the complete nucleotide sequence of a nuclear-encoded gene from an extinct species. We found two alleles and show that one allele produces a functional protein whereas the other one encodes a protein with strongly reduced activity. This finding suggests that mammoths may have been polymorphic in coat color, with both dark- and light-haired individuals co-occurring.     

Metabolism of carbohydrate in alimentary tract of reindeer in winter

The study was conducted on six reindeers in December. It was established that concentration of reducing sugars in the chyme of jejunum increases substantially (6 times in comparison with abomasum), whereas concentration cellulose, on the contrary, decreases (4.5 times). The maximal increase of monosaccharides in the small intestine testifies to formation of metabolic fund of sugars in this part of the alimentary tract due to high degree of polysaccharides hydrolysis of exogenous, as well as endogenous, microbial formation. Obtained data assume that the need of the reindeer for glucose is provided for not only by gluconeogenesis as it was considered before, but also by absorption of monosaccharides from the alimentary tract.     

Orangutan movement and population dynamics across human-modified landscapes: implications of policy and management

Landscape Ecology - Agricultural expansion is a leading cause of deforestation and habitat fragmentation globally. Policies that support biodiversity and facilitate species movement across farmland...     

Successful transmission of a retrovirus depends on the commensal microbiota

To establish chronic infections, viruses must develop strategies to evade the host's immune responses. Many retroviruses, including mouse mammary tumor virus (MMTV), are transmitted most efficiently through mucosal surfaces rich in microbiota. We found that MMTV, when ingested by newborn mice, stimulates a state of unresponsiveness toward viral antigens. This process required the intestinal microbiota, as antibiotic-treated mice or germ-free mice did not transmit infectious virus to their offspring. MMTV-bound bacterial lipopolysaccharide triggered Toll-like receptor 4 and subsequent interleukin-6 (IL-6)-dependent induction of the inhibitory cytokine IL-10. Thus, MMTV has evolved to rely on the interaction with the microbiota to induce an immune evasion pathway. Together, these findings reveal the fundamental importance of commensal microbiota in viral infections.     

The Effect of Sulfated (1→3)-α-L-Fucan from the Brown Alga Saccharina cichorioides Miyabe on Resveratrol-Induced Apoptosis in Colon Carcinoma Cells

Accumulating data clearly indicate that the induction of apoptosis by nontoxic natural compounds is a potent defense against the development and progression of many malignancies, including colon cancer. Resveratrol and the fucoidans have been shown to possess potent anti-tumor activity in vitro and in vivo. The aim of the present study was to examine whether the combination of a fucoidan from the brown alga Saccharina cichorioides Miyabe and resveratrol would be an effective preventive and/or therapeutic strategy against colon cancer. Based on NMR spectroscopy and MALDI-TOF analysis, the fucoidan isolated and purified from Saccharina cichorioides Miyabe was (1→3)-α-L-fucan with sulfate groups at C2 and C4 of the α-L-fucopyranose residues. The fucoidan enhanced the antiproliferative activity of resveratrol at nontoxic doses and facilitated resveratrol-induced apoptosis in the HCT 116 human colon cancer cell line. Apoptosis was realized by the activation of initiator caspase-9 and effector caspase-7 and -3, followed by the cleavage of PARP. Furthermore, significant inhibition of HCT 116 colony formation was associated with the sensitization of cells to resveratrol by the fucoidan. Taken together, these results demonstrate that the combination of the algal fucoidan with resveratrol may provide a potential therapy against human colon cancer.     

Circadian polymorphisms associated with affective disorders

Background  

Clinical symptoms of affective disorders, their response to light treatment, and sensitivity to other circadian interventions indicate that the circadian system has a role in mood disorders. Possibly the mechanisms involve circadian seasonal and photoperiodic mechanisms. Since genetic susceptibilities contribute a strong component to affective disorders, we explored whether circadian gene polymorphisms were associated with affective disorders in four complementary studies.     

Identification and Characterization of a Novel Lectin from the Clam Glycymeris yessoensis and Its Functional Characterization under Microbial Stimulation and Environmental Stress

Lectin from the bivalve Glycymeris yessoensis (GYL) was purified by affinity chromatography on porcine stomach mucin–Sepharose. GYL is a dimeric protein with a molecular mass of 36 kDa, as established by SDS-PAGE and MALDI-TOF analysis, consisting of 18 kDa subunits linked by a disulfide bridge. According to circular dichroism data, GYL is a β/α-protein with the predominance of β-structure. GYL preferentially agglutinates enzyme-treated rabbit erythrocytes and recognizes glycoproteins containing O-glycosidically linked glycans, such as porcine stomach mucin (PSM), fetuin, thyroglobulin, and ovalbumin. The amino acid sequences of five segments of GYL were acquired via mass spectrometry. The sequences have no homology with other known lectins. GYL is Ca²⁺-dependent and stable over a range above a pH of 8 and temperatures up to 20 °C for 30 min. GYL is a pattern recognition receptor, as it binds common pathogen-associated molecular patterns, such as peptidoglycan, LPS, β-1,3-glucan and mannan. GYL possesses a broad microbial-binding spectrum, including Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli, Vibrio proteolyticus), but not the fungus Candida albicans. Expression levels of GYL in the hemolymph were significantly upregulated after bacterial challenge by V. proteolyticus plus environmental stress (diesel fuel). Results indicate that GYL is probably a new member of the C-type lectin family, and may be involved in the immune response of G. yessoensis to bacterial attack.     

Diverse phytoplasmas associated with leguminous crops in Russia

A large scale survey of diseased legume plants (mainly clover and alfalfa in the Fabaceae family) was conducted from 2009 to 2013 in four Economic Regions of Russia, Northern (Arkhangelsk and Vologda oblast), Central (Moscow oblast), Volga (Samara oblast) and West Siberian (Novosibirsk oblast). The majority of infected clover plants exhibited symptoms typical of clover phyllody (CPh), clover yellow edge (CYE), or clover proliferation (CP), and infected alfalfa plants exhibited symptoms typical of alfalfa witches’-broom (AWB). Of 161 symptomatic plants from 22 different legume species, 103 tested positive for phytoplasma infection. Phytoplasmas belonging to four groups and six subgroups were detected, of which 31.1% were group 16SrI, with the majority belonging to subgroup 16SrI-C- (causal agent of CPh disease), two belonging to 16SrI-B and two group 16SrI phytoplasmas not identified to the subgroup level;47.6% were group 16SrIII, with the majority belonging to subgroup 16SrIII-B or 16SrIII-B variant (causal agent of CYE disease), and one strain belonging to16SrIII-F; 8.7% were subgroup 16SrVI-A (causal agent of CP and AWB diseases); 9.7% were subgroup 16SrXII-A (causal agent of AWB disease); and 2.9% were mixed infected with subgroups 16SrIII-B and 16SrI-C. The predominant phytoplasma species detected varied by region. In the Northern and Central Regions, the majority of the phytoplasmas detected belonged to subgroups 16SrI-C and 16SrIII-B. In the West Siberian and the Volga Regions, the phytoplasmas predominately detected belonged to subgroups 16SrVI-A and 16SrXII-A, respectively. Subgroup 16SrIII-F was detected in a single plant in the West Siberian Region and a mixed infection of 16SrIII-B and 16SrI-C was detected in three plants, one in the Northern Region and two in the Central Region. Eleven species of insects of the order Hemiptera, suborder Auchenorrhyncha, were collected from leguminous plants in the Moscow oblast of the Central Region. Euscelis incisus and Aphrodes bicinctus were the most prevalent species and may be potential phytoplasma vectors in the Central Region.     

6-Bromohypaphorine from Marine Nudibranch Mollusk Hermissenda crassicornis is an Agonist of Human α7 Nicotinic Acetylcholine Receptor

6-Bromohypaphorine (6-BHP) has been isolated from the marine sponges Pachymatisma johnstoni, Aplysina sp., and the tunicate Aplidium conicum, but data on its biological activity were not available. For the nudibranch mollusk Hermissenda crassicornis no endogenous compounds were known, and here we describe the isolation of 6-BHP from this mollusk and its effects on different nicotinic acetylcholine receptors (nAChR). Two-electrode voltage-clamp experiments on the chimeric α7 nAChR (built of chicken α7 ligand-binding and glycine receptor transmembrane domains) or on rat α4β2 nAChR expressed in Xenopus oocytes revealed no action of 6-BHP. However, in radioligand analysis, 6-BHP competed with radioiodinated α-bungarotoxin for binding to human α7 nAChR expressed in GH₄C₁ cells (IC₅₀ 23 ± 1 μM), but showed no competition on muscle-type nAChR from Torpedo californica. In Ca²⁺-imaging experiments on the human α7 nAChR expressed in the Neuro2a cells, 6-BHP in the presence of PNU120596 behaved as an agonist (EC₅₀ ~80 μM). To the best of our knowledge, 6-BHP is the first low-molecular weight compound from marine source which is an agonist of the nAChR subtype. This may have physiological importance because H. crassicornis, with its simple and tractable nervous system, is a convenient model system for studying the learning and memory processes.