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Dehydrins (DHN) belong to the late embryogenesis abundant II family and have been found to enhance plant tolerance to abiotic stress. In the present study, we reported four DHNs in Larix kaempferi (LkDHN) which were identified from the published transcriptome. Alignment analysis showed that these four LkDHNs shared close relationships and belonged to SK3-type DHNs. The electrophoretic mobility shift assay indicated that these four LkDHNs all possess sequence-independent binding capacity for double-strands DNAs. The subcellular localizations of the four LkDHNs were in both the nucleus and cytoplasm, indicating that these LkDHNs enter the nucleus to exert the ability to bind DNA. The preparation of tobacco protoplasts with different concentrations of mannitol showed that LkDHNs enhanced the tolerance of plant cells under osmotic stress. The overexpression of LkDHNs in yeasts enhanced their tolerance to osmotic stress and helped the yeasts to survive severe stress. In addition, LkDHNs in the nucleus of salt treated tobacco increased. All of these results indicated that the four LkDHNs help plants survive from heavy stress by participating in DNA protection. These four LKDHNs played similar roles in the response to osmotic stress and assisted in the adaptation of L. kaempferi to the arid and cold winter of northern China. [ABSTRACT FROM AUTHOR]

Drought is one of the major factors limiting rice yield worldwide. A total of 46 hybrid rice varieties were chosen to investigate their root distribution and their response to drought. A field experiment was carried out in a dry shed building to evaluate the drought tolerance capacity of hybrid rice varieties on the basis of CTIRDE (complex tolerance index of rice under drought environment) values. Next, the experiment was conducted in a specially designed pot system and seed bags to analyze the root distribution and activity of antioxidant enzymes in different rice varieties. Moreover, the DEEPER ROOTING 1 (DRO1) gene was sequenced to elucidate its role in the root distribution of typical rice varieties. On the basis of CTIRDE values, the 46 hybrid rice varieties were classified as tolerant (CTIRDE ≥ 0.75), semi-tolerant (0.75 > CTIRDE > 0.65), or sensitive (CTIRDE ≤ 0.65) to drought stress. The tolerant varieties (Chuanguyou208 and Deyou4727) displayed a significantly larger length, had higher number and weight of roots in the 30–50 cm soil layer, and exhibited a significantly higher activity of Superoxide dismutase (SOD) and Peroxidase (POD) enzymes in roots during the drought stress period. The DRO1 gene sequencing results revealed that the tolerant and sensitive varieties exhibited a single-nucleotide polymorphism (SNP) in the 3-exon region, and the tolerant varieties (Chuanguyou208 and Deyou4727) exhibited a larger root growth angle with the horizontal axis, hence developing a deeper root system as compared with the other two group varieties. A significant correlation was found not only between the DRO1 gene and root distribution but also between DRO1 and the activity of SOD and POD enzymes. Conclusively, as a key feature, a deep root system enabled tolerant rice varieties (Chuanguyou208 and Deyou4727) to avoid drought stress by absorbing more water stored in deep soil layers. The root distribution, activity of POD and SOD enzymes in roots, and DRO1 gene can be used to screen tolerant rice varieties that can survive better under drought stress during the seedling stage of rice growth. [ABSTRACT FROM AUTHOR]

Cytokines play an important role in the pathogenesis of hypertension. The authors hypothesized that interleukin 17 (IL-17) might contribute to the prehypertensive state. This study evaluated the relationship between serum levels of IL-17 and prehypertension. A total of 394 participants were enrolled, after excluding for hypertension or treated hypertension, and divided into two groups (optimal blood pressure [BP] and prehypertension) based on the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure classification of BP. Optimal BP was defined as systolic BP <120 mm Hg and diastolic BP <80 mm Hg. Prehypertension was defined as systolic BP of 120 to 139 mm Hg or diastolic BP of 80 to 89 mm Hg. IL-17A levels were determined by enzyme-linked immunosorbent assay. The mean serum IL-17 concentration in the prehypertension group was significantly higher than in the optimal BP group. The cohort was divided into quartiles Q1 (≤3.5 ng/L), Q2 (3.60 to 6.10 ng/L), Q3 (6.20 to 10.00 ng/L), and Q4 (≥10.10 ng/L) based on IL-17 levels. The Q2 to Q4 groups had increasing odds ratios for having prehypertension compared with the Q1 group. Elevated serum IL-17 was accompanied by a rise in systolic BP. Thus, increased serum IL-17 levels are associated with prehypertension. [ABSTRACT FROM AUTHOR]

• Water use indicators of wheat production were modelled at high spatial resolution. • Irrigation in water-scarce northern regions caused the larger environmental impacts. • Hotspot regions accounted for 34% of the cropping area but 61% of irrigation. • Paradoxically, gains in total water efficiency have led to increased water scarcity. Water shortage is a critical constraint limiting China's capacity for food security. To provide evidence supporting environmentally sustainable water use in food production, this study compared irrigation water productivities (IWPs) and water-scarcity footprints (WSFs) for China's wheat production at high spatial resolution. Contrary to previous water productivity studies assessing crop yield over total water consumption, it was found that IWPs in China's water-scarce northern regions were much lower than those in water-rich southern regions. The WSFs further demonstrated the larger environmental impacts resulting from irrigation in water-scarce northern regions. Hotspot regions, having IWPs in the lowest tercile (<5.2 kg m−3) and WSFs in the highest tercile (>0.058 m3 H 2 O e kg − 1), were mainly located in the Huang-Huai-Hai and northwestern regions and accounted for 34% of the cropping area but 61% of irrigation water use. Historically, the south was also an important contributor of China's wheat production, but progressive shifts toward highly resource-efficient cropping in the Huang-Huai-Hai region has occurred. The paradox is that gains in total crop water efficiency have led to increased irrigation demand and water scarcity. Today, croplands suitable for wheat production lie fallow in some southern regions in the winter. A national reassessment of this situation is urgently needed. [ABSTRACT FROM AUTHOR]