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Parkinson's disease (PD) seriously threatens human's health. Researches have shown a close correlation between long non-coding RNAs (lncRNAs) and PD. However, the biological function of lncRNA homeobox transcript antisense RNA (HOTAIR) in PD remains largely unknown. In this study, we established PD models in vivo and in vitro by using 1-methyl-4-phenyl-2, 3, 6-tetrahydropyridine (MPTP) and 1-methyl-4-phenylpyridinium (MPP+) to assess the role of HOTAIR in pyroptotic cell death and neuronal damage. RNA immunoprecipitation (RIP) and dual luciferase reporter assay were used to verify the interaction between miR-326 and HOTAIR or ELAV like RNA binding protein 1 (ELAVL1). LncRNA HOTAIR was upregulated in PD mice and MPP+ induced SH-SY5Y cells. Additionally, knockdown of HOTAIR notably attenuated the symptom of PD in vivo. Downregulation of HOTAIR could obviously promoted cell viability and suppressed NLR family pyrin domain containing 3 (NLRP3) mediated pyroptotic cell death of SH-SY5Y cells in the presence of MPP+. Further, lncRNA HOTAIR positively regulated ELAVL1 expression by targeting miR-326, and downregulation of HOTAIR or ELAVL1 notably suppressed promotive effects of miR-326 inhibitor on MPP+ induced pyroptosis via activation of NLRP3 inflammasome. Collectively, HOTAIR silencing significantly inhibits neuronal damage through repressing NLRP3 mediated pyroptosis activation via regulation of miR-326/ELAVL1 axis in PD, which may contribute to a better understanding of PD pathogenesis and provide new treatment strategies for this disease.

The effects of elevated CO2 concentration and drought on the chemical composition and decomposition of spring wheat (Triticum aestivum L.) leaf litter were investigated. The results obtained were as follows: (i)�decomposition of leaf litter material grown under elevated CO2 and drought (ED) was significantly reduced (P=0.007), but no significant changes occurred under elevated CO2 (EW) (P=0.203) or drought (AD) (P=0.599). The loss of mass of leaf litter material decomposing under ambient CO2 (AW) was higher than that under AD and ED, but the difference between AW and EW was insignificant (P=0.318); (ii) compared with leaf litter material from plants grown under AW, ED litter had higher total C content, despite decreased soluble carbohydrates, and lower total N content, and hence increased C/N ratio; (iii) tannins and lignin were not significantly correlated with the loss of mass, but increased concentrations of lignin and tannins in the decomposing wheat material might reduce the rate of litter turnover in later stages of decomposition; (iv) the decreased decomposition rate at ED was the result of an increase in the C/N ratio, a decrease in total N content, and inhibition of soil microbial activity by drought. So there will be the need to increase external N inputs and decrease stalks to the spring wheat field to increase decomposition rates if CO2 concentration increases and semi-arid regions become drier in the future.

Adiantum reniforme var. sinensis (Adiantaceae) is an endangered fern endemic to the Th ree Gorges region in southwest China. To elucidate possible ecophysiological mechanisms restricting its distribution, eff ects of the availability of light (28%, 14% and 7% of open fi eld) and soil moisture (60% and 40% of fi eld capacity) on dry matter production and allocation, leaf morphology and water use effi ciency (WUE) were examined in A. reniforme var. sinensis and its widespread congener A. capillus-veneris . Both species had lower root/shoot ratio (R/S) and higher specifi c leaf area (SLA) when grown at low light. However, A. reniforme var. sinensis showed less plasticity for total leaf area (LA) and leaf area ratio (LAR) than A. capillus-veneris , and its root mass, total mass and WUE decreased as light availability decreased. Under water stress, all traits of both species except WUE were signifi cantly aff ected. However, drought stress decreased total mass of A. capillus-veneris but did not have a signifi cant eff ect on A. reniforme var. sinensis . Compared with A. capillus-veneris , A. reniforme var. sinensis had signifi cantly higher R/S but lower values for other analyzed traits. Th ese results suggest that A. reniforme var. sinensis is relatively superior in drought tolerance but inferior at low light, allowing it to persist in habitats with low soil moisture and high light availability but with few coexisting species present.

Paspalum distichum, Cynodon dactylon and Hemarthria altissima distribute widely in natural water fluctuation zone of the Three Gorges region. To investigate whether they are suitable for growing in the artificial water fluctuation zone, which has longer submergence time and different submergence rhythm, of the Three Gorges reservoir, three complete submergence depths (0.5, 1 and 2 m) were conducted for about 6 months (from 12 November 2007 to 30 April 2008), and the survival and recovery growth of the three species were recorded after re-emergence for two weeks. The three species could start recovery growth within one week and more than 50% plants could survive. Among the three species, P. distichum had the largest increments in branch number and maximum stem length, and the smallest root shoot ratio. C. dactylon, however, had the smallest maximum stem length increment, and its survival and branch number increment were both larger than those of H. altissima. For C. dactylon and H. altissima, the survival and branch number increment significantly increased, while maximum stem length increment tended to decrease when submergence depth went higher. For P. distichum, the survival and the shoot mass were the lowest after 2 m submergence depth, but the other parameters were not different among different submergence treatments. Compared with control plants, submergence increased root shoot ratio of C. dactylon and H. altissima, but did not affect that of P. distichum. These results demonstrated that the three species are submergence-tolerant and can be applied in vegetation reconstruction in water fluctuation zone of the Three Gorges reservoir. Meanwhile, the results also suggested that the three species developed different survival tactics during the long-term submergence.

Acid rain is leading to soil potassium (K) loss. A hydroponic experiment was conducted to determine the growth and physiological and stoichiometrical traits of Mosla hangchowensis (an endangered plant) and M. scabra (a weed) in response to three K concentrations. For M. hangchowensis, compared with standard Knop’s solution (K3), low K (K0) induced reductions in net photosynthetic rate, soluble protein content, superoxide dismutase activity, total biomass, tissue K concentration, and leaf nitrogen (N) concentration and induced increases in malondialdehyde content and tissue sodium (Na) concentration (P , 0.05). In contrast, none of these factors were affected by K0 for M. scabra. Critical values of N/K and K/P (phosphorus) ratios in shoots indicated that limitation in K uptake occurred for M. hangchowensis but not M. scabra under K0. The continuing decline of K content due to acid rain may worsen the situation of M. hangchowensis, whereas M. scabra can maintain vigorous growth and develop well in the future.

The effects of soil moisture (80%, 60% and 40% water holding capacity) on dry matter production and allocation, leaf morphological and physiological characteristics were examined in Adiantum reniforme var. sinensis, an endangered fern endemic to the Three Gorges region in southwest China. Drought stress decreased leaf growth and photosynthetic capacity, and hence reduced total mass, specific leaf area (SLA) and leaf area ratio (LAR). Dry matter allocation into the root fraction, however, increased with decreasing soil moisture. Leaf relative water content (RWC) decreased as soil water depletion, but the differences were insignificant. Such results might be the result of a physiological balance between the demand for water by the leaves and the water uptake from soil by the roots. The decrease in stomatal conductance (gs) effectively controlled water loss and maintained intrinsic water use efficiency (WUEi) under drought stress. The increase in proline content might contribute to osmotic adjustmen...

Leaf mass per unit area (LMA), carbon and nitrogen contents, leaf construction cost, and photosynthetic capacity (P max) of Adiantum reniforme var. sinensis, an endangered fern endemic to the Three Gorges region in southwest China, were compared in five populations differing in habitat such as soil moisture and irradiance. The low soil moisture and high irradiance habitat population exhibited significantly higher LMA, area-based leaf construction (CCA), and carbon content (CA), but lower leaf nitrogen content per unit dry mass (NM) than the other habitat populations. The high soil moisture and low irradiance habitat populations had the lowest CCA, but their cost/benefic ratios of CCA/P max were similar to the medium soil moisture and irradiance habitat population due to their lower leaf P max. Hence A. reniforme var. sinensis prefers partially shaded, moist but well-drained, slope habitats. Due to human activities, however, its main habitats now are cliffs or steeply sloped bare rocks with poor and thin soil. The relatively high energy requirements and low photosynthetic capacity in these habitats could limit the capability of the species in extending population or interspecific competition and hence increase its endangerment.

The photosynthetic and growth characteristics of Mosla hangchowensis, an endangered species and M. dianthera, a weed, were compared under three irradiances (PPFD) similar to shaded forest understory, forest edge and open land. Both species grown at lower PPFD had lower PPFD-saturated photosynthetic rate (Pmax), saturation PPFD, compensation PPFD, apparent quantum yield, total mass and root/shoot ratio and higher specific leaf area, leaf area ratio and height ratio. At the same PPFD treatment, however, specific leaf area and leaf area ratio of M. hangchowensis were higher than those of M. dianthera, other above parameters were lower than those of M. dianthera. Water use efficiency did not differ between M. hangchowensis and M. dianthera, but it reached its maximum at 70 % of full PPFD. These results suggested the optimum habitat of M. hangchowensis is the forest edge.

Stomatal density (SD) and stomatal index (SI) on the abaxial flag leaf epidermis, gas exchange of flag leaves and yield of six wheat ( Triticum aestivum L.) cultivars differing in drought resistance were studied in plant growth chamber. There were significant differences among cultivars in SD, SI, epidermal cell density (ED), photosynthetic rate (P n ), transpiration rate (E), instantaneous transpiration efficiency (ITE), shoot dry weight yield (Ys), grain yield (Yd) and whole growth season water use efficiency (WUE), but not in stomatal conductance (g s ). Wheat cultivars with moderate drought resistance had higher P n and Yd than cultivars with strong or weak drought resistance. SD was negatively correlated with ITE (r=−0.85) and WUE (r=−0.84), but not with P n , E and Yd. There were significant relationships between ED and Yd (r=−0.92), between SI and P n (r=0.84). These results revealed that breeding wheat cultivar only to raise drought resistance might cause yield decrease when water stress was not t...

Photosynthetic and growth characteristics of Mosla chinensis and M. scabra were compared at three irradiances similar to shaded forest understory, forest edge, and open land. At 25 % full ambient irradiance, M. chinensis and M. scabra had similar photosynthetic characteristics, but saturation irradiance, compensation irradiance, and apparent quantum yield of M. chinensis were higher than those of M. scabra at full ambient irradiance and 70 % full ambient irradiance. At the same irradiance treatment, specific leaf area and leaf area ratio of M. chinensis were lower than those of M. scabra. Photon-saturated photosynthetic rate and water use efficiency of M. chinensis, however, were not significantly higher than those of M. scabra, and the leaf area and total biomass were lower than those of M. scabra. As a sun-acclimated plant, the not enough high photosynthetic capacity and lower biomass accumulation may cause that M. chinensis has weak capability to extend its population and hence be concomitant in the community.

Wheat (Triticum aestivum L.) is one of the most important food sources in the world. The potential impacts of elevated CO2 on wheat yield and grain quality will have profound influences on the supply and nutritional value of wheat products as well as on many industrial sectors. A growth-chamber experiment was designed to estimate how soil moisture influences the potential effects of elevated CO2 concentration ([CO2]) on wheat growth, water use and grain yield. Spring wheat (T. aestivum cv. Ganmai 8139) was grown in pots placed in controlled growth chambers and was subjected to two [CO2] (approximately 350 and 700l/l, respectively) and two soil water levels (80 and 40% of field water capacity (FWC), respectively). High [CO2] increased plant shoot dry weight by 89% under 80% FWC and by 53% under 40% FWC. Grain yield of wheat was markedly increased under elevated [CO2] with greater grain number and harvest index. The ratio of plant shoot dry weight to height was increased by 75% under high [CO2] at high soil moisture, and by 54% at low moisture. Water use efficiency of shoot (WUEs) and grain yield (WUEg) were increased under high [CO2] because the magnitude of the increase in shoot dry weight and grain yield was greater than that of the cumulative consumption of water under high [CO2] conditions. When wheat plants were under high [CO2] conditions and maintained at high moisture, the WUEs and WUEg were increased by 62 and 128%, respectively. Elevated [CO2] resulted in lower concentrations of mineral nutrients (N, P, K and Zn), lysine and crude protein in mature grains. This was probably caused by a dilution effect induced by great increment of carbohydrate in grains. The total quantity of mineral nutrients, lysine and crude protein accumulated in grains per hectare were still increased under high [CO2] due to increase in grain yield. Our results indicate that high [CO 2] is beneficial to plant growth, yield and WUE, while grain quality was lowered under high [CO2] conditions as reflected by the increased crude starch content, and corresponding decreases in mineral nutrients, lysine and crude protein concentrations. The analysis of yield components suggested that the yield increase was mainly attributable to an increase in the number of grains. However, the effects of CO 2 enrichment on plants depend on the availability of soil moisture, and plants may benefit more from CO 2 enrichment when sufficient water is supplied. © 2004 Elsevier B.V. All rights reserved.

We compared the photosynthetic traits in response to soil water availability in an endangered plant species Mosla hangchowensis Matsuda and in a weed Mosla dianthera (Buch.-Ham.) Maxim. The highest diurnal mean net photosynthetic rate (PNmean), stomatal conductance (gs), and water use efficiency (WUE) of both species occurred at 60 % soil water holding capacity (WHC), while the lowest values occurred at 20 % WHC. The PNmean, gs, and chlorophyll (Chl) a and b contents of M. hangchowensis were lower than those of M. dianthera, while the physiological plasticity indices were higher than those of M. dianthera. M. hangchowensis had strong adaptability to the changing soil water status but weak extending population ability in its habitats because of the low PNmean, which may be one of the causes of its endangerment.