Relationships between the Arctic and the Antarctic cyanobacteria; three Phormidium-like strains evaluated by a polyphasic approach

Selected strains of filamentous Phormidium-like cyanobacteria isolated from two Arctic regions (Ellesmere Island, High Canadian Arctic and Svalbard) and from Antarctica (Antarctic peninsula, South Shetland Islands and South Orkney Islands) were studied. The polyphasic approach used included phenotypic observations of morphological features and genotypic analyses (restriction fragment length polymorphism of 16S rRNA gene, internal transcribed space, 16S rRNA gene sequence analysis). Although genotypes generally correspond to observed morphotypes, the genetic analyses revealed a high degree of biodiversity that could not be unveiled using solely morphological evaluations. According to the phylogenetic analysis, the three clones were divided into two major clades, indicating that the phylogenetic distance between Arct-Ph5/Ant-Ph68 and Ant-Ph58 was so large they belonged to different genera. The polyphyletic position of strains of the genus Phormidium was confirmed by this study, attesting the need to entirely revise classification in this taxon in the future.     

Species immigration, extinction and turnover of vascular plants in boreal lakes

Dictated by limited resource availability for land acquisition, a central question in conservation biology is the ability of areas of different size to maintain species diversity. The selected reserves should not only be species rich at the moment, but should also maintain species diversity in the long run. We used two sets of data on vascular plant species in boreal lakes collected in 1933/34 and 1996 to test the relationships between lake area and the extinction, immigration and turnover rates of the species. Moreover, we investigated, whether the number of species in 1933/34 or water connection between lakes was related to extinction, immigration and turnover rates of species. We found that lake area or shoreline length was not correlated with immigration or turnover rate. But extinction rate was slightly negatively correlated with shoreline length. The original number of species was positively related to the number of species extinctions and to the absolute turnover rate in the lakes, which indicates that species richness does not create stability in these communities. Species number was not correlated with immigration rate. Upstream water connections in the lakes did not affect immigration, extinction or turnover rates. We conclude that length of the shoreline is a better measure of suitable area for water plants than the lake area, and that because the correlation between shoreline length and extinction rate was slight, also small lakes can be valuable for conservation.     

Comparative analysis of food-finding behavior of an herbivorous and a carnivorous land snail

Abstract. Although the olfactory capabilities of land snail tentacles have been tested by lesion studies and unilateral exposure of tentacles to specific odors, studies of a carnivorous species suggest that the anatomical similarities of herbivorous and carnivorous land snails may belie a fundamental difference in the way these structures are used to find food. Therefore, we challenged the herbivore, Anguispira alternata , and the carnivore, Haplotrema concavum , to find a stationary food source (carrot and caged young prey snail, respectively) under identical still air conditions. The herbivore traveled a significantly shorter distance to the food, even negotiating a barrier placed halfway between the snail and its food. The carnivore, on the other hand, followed a circuitous, apparently random, path to the food. Subsequent tests revealed that H. concavum readily follows prey slime trails while A. alternata seldom follows conspecific slime trails when a distant food source is available. These results are consistent with what might be expected as adaptations to the usually mobile nature of carnivore prey and the stationary nature of herbivore food plants. The ability of A. alternata to exhibit typical detour behavior is noted.     

UPF1 reduces C9orf72 HRE-induced neurotoxicity in the absence of nonsense-mediated decay dysfunction

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Dissecting ELANE neutropenia pathogenicity by human HSC gene editing

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Predicting ROR1/BCL2 combination targeted therapy of small cell carcinoma of the lung

Small cell lung cancer (SCLC) remains a deadly form of cancer, with a 5-year survival rate of less than 10 percent, necessitating novel therapies. Receptor tyrosine kinase-like orphan receptor 1 (ROR1) is an oncofetal protein that is emerging as a therapeutic target and is co-expressed with BCL2 in multiple tumor types due to microRNA coregulation. We hypothesize that ROR1-targeted therapy is effective in small cell lung cancer and synergizes with therapeutic BCL2 inhibition. Tissue microarrays (TMAs) and formalin-fixed paraffin-embedded (FFPE) SCLC patient samples were utilized to determine the prevalence of ROR1 and BCL2 expression in SCLC. Eight SCLC-derived cell lines were used to determine the antitumor activity of a small molecule ROR1 inhibitor (KAN0441571C) alone and in combination with the BCL2 inhibitor venetoclax. The Chou-Talalay method was utilized to determine synergy with the drug combination. ROR1 and BCL2 protein expression was identified in 93% (52/56) and 86% (48/56) of SCLC patient samples, respectively. Similarly, ROR1 and BCL2 were shown by qRT-PCR to have elevated expression in 79% (22/28) and 100% (28/28) of SCLC patient samples, respectively. KAN0441571C displayed efficacy in 8 SCLC cell lines, with an IC50 of 500 nM or less. Synergy as defined by a combination index of <1 via the Chou-Talalay method between KAN0441571C and venetoclax was demonstrated in 8 SCLC cell lines. We have shown that ROR1 inhibition is synergistic with BCL2 inhibition in SCLC models and shows promise as a novel therapeutic target in SCLC.Subject terms: Cancer genetics, Targeted therapies, Small-cell lung cancer     

Revised ranges of seagrass species in the Myeik Archipelago, Myanmar

In a survey of the Myeik Archipelago, we documented seven seagrass species in the southern region. Three seagrass species (Cymodocea rotundata, Enhalus acoroides, and Halophila ovalis) have previously been reported in the Myeik Archipelago; three species (Halodule pinifolia, Halodule uninervis, Syringodium isoetifolium) are new reports for the archipelago; and one species (Thalassia hemprichii) is a new report for Myanmar.     

Impacts of co-occurring environmental changes on Alaskan stream fishes

1. Freshwater fishes are now facing unprecedented environmental changes across their northern ranges, especially due to rapid warming occurring at higher latitudes. However, empirical research that examines co-occurring environmental effects on northern fish communities remains limited.
2. We used fish community data from 1587 Alaskan stream sites to examine the potential combined and interacting effects of climate change, current weather, habitat, land use, and fire on two community-level metrics (species richness, relative abundance), and on the distributions of three Alaskan fish species.
3. Our models were 71–76% accurate in predicting the distribution of Alaskan stream fishes using a combination of climate and habitat variables. In contrast to other freshwater ecosystems that are most threatened by land use pressures, we did not detect any evidence for the potential stress of anthropogenic land use or fire on stream fishes.
4. Warming temperatures increased overall community richness and abundance but produced differing responses at the species level. Juvenile salmon presence was positively associated with several climate variables including warmer spring and autumn temperatures and wetter summers. In comparison, warmer seasonal temperatures contributed to declines for northern-adapted species such as Arctic grayling and Dolly Varden.
5. This study highlights the overarching role of current and changing climate in regulating northern stream fish biodiversity. Although many fish species may benefit from climate change across their northern ranges, localised declines are likely to occur and may prove detrimental for communities with limited fishing portfolios. Climate change adaptation and mitigation strategies customised for rapidly changing northern ecosystems will play an essential role in preserving ecologically unique northern species.