Project description:Male and female 2- and 3-years old brown bear from the region of Tackasen (Sweden) were captured in summer and winter. Muscle biopsies from vastus lateralis were collected in february (hibernation state) and june (active period). Total RNA were extracted from muscle tissue and full transcriptome analysis (RNA Seq) were performed. Statistical analysis were performed to winter versus summer comparison from matched paired samples
Project description:Brown bears (Ursus arctos) hibernate for 5-7 months without eating, drinking, urinating and defecating at a metabolic rate of only 25% of the summer activity rate. Nonetheless, they emerge healthy and alert in spring. We analyzed the physiological adaptations for hibernation by comparing the proteome, metabolome, and hematologic features of blood from hibernating and active free-ranging sub-adult brown bears with a focus on conservation of health and energy. We found that the concentrations of most plasma proteins and white blood cell types decreased during hibernation. Strikingly, antimicrobial defense proteins increased in concentration. Central functions in hibernation involving the coagulation response and protease inhibition, as well as lipid transport and metabolism, were upheld by increased levels of very few key or broad-specificity proteins. A dramatic 45-fold increase in sex-hormone-binding-globulin SHBG levels during hibernation draws, for the first time, attention to its significant but unknown role in maintaining hibernation physiology. We propose that energy for the costly protein synthesis is reduced by three mechanisms, (i) dehydration, which increases protein concentration without de novo synthesis; (ii) reduced protein degradation rates due to a 6°C reduction in body temperature, decreased protease activity, and increased plasma viscosity; and (iii) a marked redistribution of energy resources only increasing de novo synthesis of few key proteins. This comprehensive global data identified novel biochemical strategies for bear adaptations to the extreme condition of hibernation, and have implications for our understanding of physiology in general.
Project description:The genome structrure of domesticated species is influenced by complexity of breeding practices exercised by humans. Hokkaido is the northern-most regio of Japan, and one of northern limit of rice cultivation of world. The climatic conditions of Hokkaido are considered to be unsuitable for rice cultivation. Rice breeding programs of Hokkaido have focused on adaptability to specific local environmental condiitons (such as short growth period, low temperature conditions). These specific selection pressures have generated the unique genetic structures of Hokkaido rice cultivars. The genotype of sixty-three Hokkaido rice varieties were already analyzed by SSR marker, and the results showed that Hokkaido rice varieties were classified into six groups (Shinada et al, 2014). The unique genomic structures of six groups may have related to specific gene expression. This study analyze the gene expression profiles of Hokkaido rice variety.