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101.
Tino Kreszies Stella Eggels Victoria Kreszies Alina Osthoff Nandhini Shellakkutti Jutta A. Baldauf Viktoria V. Zeisler-Diehl Frank Hochholdinger Kosala Ranathunge Lukas Schreiber 《Plant, cell & environment》2020,43(2):344-357
Wild barley, Hordeum vulgare spp. spontaneum, has a wider genetic diversity than its cultivated progeny, Hordeum vulgare spp. vulgare. Osmotic stress leads to a series of different responses in wild barley seminal roots, ranging from no changes in suberization to enhanced endodermal suberization of certain zones and the formation of a suberized exodermis, which was not observed in the modern cultivars studied so far. Further, as a response to osmotic stress, the hydraulic conductivity of roots was not affected in wild barley, but it was 2.5-fold reduced in cultivated barley. In both subspecies, osmotic adjustment by increasing proline concentration and decreasing osmotic potential in roots was observed. RNA-sequencing indicated that the regulation of suberin biosynthesis and water transport via aquaporins were different between wild and cultivated barley. These results indicate that wild barley uses different strategies to cope with osmotic stress compared with cultivated barley. Thus, it seems that wild barley is better adapted to cope with osmotic stress by maintaining a significantly higher hydraulic conductivity of roots during water deficit. 相似文献
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Pinheiro Kelly V. Thomaz Amanda Souza Bárbara Kunzler Metcalfe Victoria Anne Freire Natália Hogetop Brunetto André Tesainer de Farias Caroline Brunetto Jaeger Mariane Bambini Victorio Smith Christopher G. S. Shaw Lisa Roesler Rafael 《Molecular biology reports》2020,47(9):6817-6828
Molecular Biology Reports - A member of the Trk family of neurotrophin receptors, tropomyosin receptor kinase B (TrkB, encoded by the NTRK2 gene) is an increasingly important target in various... 相似文献
105.
Human disturbance from tourism and other non-consumptive activities in protected areas may be stressful to wildlife. Animals may move away in space or time to avoid human interaction. For species of particular conservation concern, such as Baird's tapirs (Tapirus bairdii) and jaguars (Panthera onca), a better understanding of how they respond to different levels and types of disturbance is needed in order to manage human visitation to parks in ways that minimize negative outcomes for wildlife. We describe the overlap in activity patterns of tapirs, jaguars, and humans at logged and unlogged sites and at places with low versus high human visitation using camera survey data from protected areas of NW Belize, 2013–2016. Tapirs were nocturnal in all study sites, with > 80% of all tapir detections occurring between 1900 hr and 0500 hr. Their activity patterns were not different in unlogged versus logged sites and did not change with increased human traffic. Jaguars were cathemeral across sites but had more nocturnal activity at the site with the most human impact. Activity pattern overlap between tapirs and jaguars did not differ significantly between logged and unlogged sites, nor between areas with low and high human activity. Human traffic increased from 2013 to 2016 at most of the study locations. In conclusion, this camera trap dataset suggests that non-consumptive human disturbance does not alter the activity patterns of tapirs and jaguars in protected areas lacking hunting pressure. 相似文献
106.
The low engraftment and retention rate of mesenchymal stem cells (MSCs) at the target site indicates that the potential benefits of MSC-based therapies can be attributed to their paracrine signaling. In this study, the extracellular matrices (ECMs) deposited by bone marrow-derived human MSCs in the presence and absence of ascorbic acid was characterized. MSCs were seeded on top of decellularized ECM (dECM) and the concentrations of proangiogenic and antiangiogenic molecules released in culture (conditioned) media was compared. Effects of ECM derived from MSCs with different passage numbers on MSC secretome was also investigated. Our study revealed that the expression of proangiogenesis-related factors were upregulated when MSCs were harvested on dECMs, irrespective of media supplementation, as compared with those cultured on tissue culture plates. In addition, dECM generated in the presence of ascorbic acid promoted the expression of proangiogenic molecules as compared with dECM-derived in absence of media supplementation. Further, it was observed that the effectiveness of dECM to stimulate proangiogenic signaling of MSCs was reduced as cell passage number was increased from P3 to P5. The proliferation as well as capillary morphogenesis of human umbilical vein endothelial cells (HUVECs) in the presence of conditioned media were enhanced compared with the normal HUVECs culture media. These data indicate that the secretory signatures of MSCs and consequently, the therapeutic efficacy of MSCs can be regulated by presentation of dECM composition and variation of its composition. 相似文献
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Victoria Cabrera-Sharp Samantha M. Mirczuk Elaine Shervill Anthony E. Michael Robert C. Fowkes 《Cell and tissue research》2013,352(3):751-760
In target tissues, cortisol is metabolised by two 11β-hydroxysteroid dehydrogenase (11βHSD) isoenzymes, namely 11βHSD1 and 11βHSD2, both of which are co-expressed in the boar testis and reproductive tract. The present study has assessed whether cortisol-cortisone metabolism in boar testis and caput epididymidis can be regulated via the gonadotrophin-cAMP signalling pathway. 11βHSD activities were measured by using a radiometric conversion assay in static tissue culture. In both testis and caput epididymidis, the net reduction of cortisone but not the net oxidation of cortisol, was significantly decreased by luteinising hormone (by 53?±?20% and 45?±?9%, respectively, P?<?0.05), forskolin (by 60?±?7% and 57?±?9%, respectively, P?<?0.01) and 8-bromo-cAMP (by 54?±?4% and 64?±?1%, respectively, P?<?0.01). This suppression of 11-ketosteroid reductase activity in the boar testis by forskolin could be attenuated by the protein kinase A (PKA) inhibitor, H89. Hence, within the boar testis and the caput epididymidis, the local actions of glucocorticoids are modulated by gonadotrophin-cAMP-PKA signalling via their selective effects on the reductase activity of 11βHSD. 相似文献
109.
Cong Zhu Ankit Gupta Victoria L. Hall Amy L. Rayla Ryan G. Christensen Benjamin Dake Abirami Lakshmanan Charlotte Kuperwasser Gary D. Stormo Scot A. Wolfe 《Nucleic acids research》2013,41(4):2455-2465
Zinc-finger nucleases (ZFNs) have been used for genome engineering in a wide variety of organisms; however, it remains challenging to design effective ZFNs for many genomic sequences using publicly available zinc-finger modules. This limitation is in part because of potential finger–finger incompatibility generated on assembly of modules into zinc-finger arrays (ZFAs). Herein, we describe the validation of a new set of two-finger modules that can be used for building ZFAs via conventional assembly methods or a new strategy—finger stitching—that increases the diversity of genomic sequences targetable by ZFNs. Instead of assembling ZFAs based on units of the zinc-finger structural domain, our finger stitching method uses units that span the finger–finger interface to ensure compatibility of neighbouring recognition helices. We tested this approach by generating and characterizing eight ZFAs, and we found their DNA-binding specificities reflected the specificities of the component modules used in their construction. Four pairs of ZFNs incorporating these ZFAs generated targeted lesions in vivo, demonstrating that stitching yields ZFAs with robust recognition properties. 相似文献