Habitat use by Siberian warbler species at a stopover site in Far Eastern Russia

Knowledge of the routes and habitat use of Siberian songbird species during migration is very limited. The goal of our study was to describe the autumnal habitat use of seven Siberian warbler species in the genera Phylloscopus, Acrocephalus, Iduna and Locustella in Far Eastern Russia. A total of 2283 individuals were trapped in mist nets placed within different habitat types between 2012 and 2014 as part of the Amur Bird Project at Muraviovka Park in Far Eastern Russia. We studied the effect of habitat type and vegetation height on the occurrence of each species, and compared our results to published information on habitat use on the breeding grounds. Our results demonstrate that most species exhibit species-specific preferences for habitat type, and that these stopover habitats were similar to habitats used on the breeding grounds. © 2018 British Trust for Ornitholog

Does Innovation Success Influence Social Interactions? An Experimental Test in House Sparrows

In group-living animals, individuals may benefit from the presence of an innovative group-mate because new resources made available by innovators can be exploited, for example by scrounging or social learning. As a consequence, it may pay off to take the group-mates' problem-solving abilities into account in social interactions such as aggression or spatial association, for example because dominance over an innovative group-mate can increase scrounging success, while spatial proximity may increase the chance of both direct exploitation and social learning. In this study, we tested whether the individuals' innovation success influences their social interactions with group-mates in small captive flocks of house sparrows (Passer domesticus). First, we measured the birds' actual problem-solving success in individual food-extracting tasks. Then, we manipulated their apparent problem-solving success in one task (by allowing or not allowing them to open a feeder repeatedly) while a new, unfamiliar group-member (focal individual) had the opportunity to witness their performance. After this manipulation, we observed the frequency and intensity of aggression and the frequency of spatial associations between the focal individuals and their manipulated flock-mates. Although flock-mates behaved according to their treatments during manipulations, their apparent problem-solving success did not affect significantly the focal individuals' agonistic behaviour or spatial associations. These results do not support that sparrows take flock-mates' problem-solving abilities into account during social interactions. However, focal individuals attacked those flock-mates more frequently that had higher actual problem-solving success (not witnessed directly by the focal individuals), although aggression intensity and spatial association by the focal birds were unrelated to the flock-mates' actual success. If this association between flock-mates' actual innovativeness and focal individuals' aggression is not due to confounding effects, it may imply that house sparrows can use more subtle cues to assess the group-mates' problem-solving ability than direct observation of their performance in simple foraging tasks

Overexpression of HGF/MET axis along with p53 inhibition induces de novo glioma formation in mice

BACKGROUND: Aberrant MET receptor tyrosine kinase (RTK) activation leads to invasive tumor growth in different types of cancer. Overexpression of MET and its ligand hepatocyte growth factor (HGF) occurs more frequently in glioblastoma (GBM) than in low-grade gliomas. Although we have shown previously that HGF-autocrine activation predicts sensitivity to MET tyrosine kinase inhibitors (TKIs) in GBM, whether it initiates tumorigenesis remains elusive. METHODS: Using a well-established Sleeping Beauty (SB) transposon strategy, we injected human and cDNA together with a short hairpin siRNA against (SB-hHgf.Met.ShP53) into the lateral ventricle of neonatal mice to induce spontaneous glioma initiation and characterized the tumors with H&E and immunohistochemistry analysis. Glioma sphere cells also were isolated for measuring the sensitivity to specific MET TKIs. RESULTS: Mixed injection of SB-hHgf.Met.ShP53 plasmids induced de novo glioma formation with invasive tumor growth accompanied by HGF and MET overexpression. While glioma stem cells (GSCs) are considered as the tumor-initiating cells in GBM, both SB-hHgf.Met.ShP53 tumor sections and glioma spheres harvested from these tumors expressed GSC markers nestin, GFAP, and Sox 2. Moreover, specific MET TKIs significantly inhibited tumor spheres\u27 proliferation and MET/MAPK/AKT signaling. CONCLUSIONS: Overexpression of the HGF/MET axis along with p53 attenuation may transform neural stem cells into GSCs, resulting in GBM formation in mice. These tumors are primarily driven by the MET RTK pathway activation and are sensitive to MET TKIs. The SB-hHgf.Met.ShP53 spontaneous mouse glioma model provides a useful tool for studying GBM tumor biology and MET-targeting therapeutics