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Background Previous studies have shown that long noncoding RNAs (lncRNAs) play a key role in cancer, including colon cancer (CC). However, the exact role of long noncoding RNA 01124 (LINC01124) in CC and its mechanisms of action remain unknown. In the present study, we aimed to investigate the functional effects and the possible mechanism of LINC01124 in CC. Results we demonstrated that LINC01124 was upregulated in colon cancer tissues and cell lines. Further functional studies showed that knockdown of LINC01124 significantly suppressed the proliferation, migration and invasion of colon cancer cells in vitro and in vivo. Moreover, in subsequent mechanistic experiments, LINC01124 was found to act as a sponge to suppress microRNA 654-5p, which targeted HAX-1. Downregulation of LINC01124 decreased the expression of HAX-1, and overexpression of a miR-654-5p inhibitor attenuated the sh-LINC01124-induced inhibition of CC cell proliferation, migration and invasion. Conclusion Collectively, all the results revealed a role for the LINC01124/miR-654-5p/HAX-1 axis in the tumorigenesis and progression of CC, suggesting that LINC01124 may be a therapeutic target for colon cancer treatment.

Unravelling the factors shaping microbial community structure across plant holobiont is required to promote plant health and crop productivity. We compared microbial communities in soils and plant compartments of two contrasting quinoa cultivars, grown in low-input cropping systems along an elevation gradient in northwest Yunnan plateau, China. With a compartment-dependent effect, alpha-diversity (Shannon and Chao1 indices) of both bacterial and fungal communities generally increased with increasing elevation. Both bacterial and fungal diversities decreased in the order of rhizosphere> root > leaf, but no significant difference was found between two plant genotypes or between bulk soil and rhizosphere. Representing a unique niche for microbial communities, leaf had a much stronger selection effect than root. With insignificant effect of plant genotype, local environmental filtering (i.e. climate, edaphic and plant traits) could have played an important role in structuring soil microbial communities, but they were weak for root and leaf endophytes, except for root fungi. The relative importance of stochastic and deterministic processes in bacterial or fungal communities varied with the elevational scale, showing contrasting patterns within each plant-associated compartment, except for leaf (determinism). The revealed distinct drives in determining the community assembly in quinoa-associated microbes are thought to be essential for underpinning plant–microbe interactions.

Background: Pineapple plant usually has a capitulum. However, a fan-shaped inflorescence was evolved in an exceptional material, having multiple crown buds. In order to reveal the molecular mechanisms of the formation of the fan-shaped inflorescence, fruit traits and the transcriptional differences between a fan-shaped inflorescence (FI) and a capitulum inflorescence (CI) pineapples were analyzed in the three tissues, i.e., the flower stem apex (FIs and CIs), the base of the inflorescence (FIb and CIb), and the inflorescence axis (FIa and CIa).Results: Except for a clear differentiation of inflorescence morphology, no significant differences in the structure of inflorescence organs and the main nutritional components (soluble solids, soluble sugar, titratable acid, and VC) in fruits were found between the two pineapples. Between the fan- and capitulum-shaped inflorescences, a total of 5370 differentially expressed genes (DEGs) were identified across the three tissues; and 3142, 2526 and 2255 DEGs were found in the flower stem apex, the base of the inflorescence, and the inflorescence axis, respectively. Of these genes, there were 489 overlapping DEGs in all three tissue comparisons. In addition, 5769 DEGs were identified between different tissues within each pineapple. Functional analysis indicated between the two pineapples that 444 transcription factors (TFs) and 206 inflorescence development related genes (IDGs) were differentially expressed in at least one tissue comparison, while 45 TFs and 21 IDGs were overlapped across the 3 tissues. Among the 489 overlapping DEGs in the 3 tissue comparisons between the two pineapples, excluding the IDGs and TFs, 80 of them revealed a higher percentage of involvement in the biological processes relating to response to auxin, and reproductive processes. RNA-seq value and real-time quantitative PCR analysis exhibited the same gene expression patterns in the three tissues. Conclusions: Our result provided novel cues for understanding the molecular mechanisms of the formation of fan-shaped inflorescence in pineapple, making a valuable resource for the study of plant breeding and the speciation of the pineapples.

Appendix: Long-term intercropping with Chinese leekdecreased thepopulations ofMeloidogynejavanica ina Sacha Inchi plantation Cheng-rong Niea, Ying Fengb,Xiao-hui Chenga,Zhi-quan Caia,c* aDepartment of Horticulture, Foshan University, Foshan 528000, China bForest Resources Conservation Center of Guang Dong Province, Guangzhou 510173, China cKey Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China. *Correspondence: zhiquan.cai@126.com 1. Supplementary text of the methods 2. Supplementary data

Background: Being a promising tropical woody oilseed crop, the evergreen and recurrent plants of Sacha Inchi (Plukenetia volubilis L.) has complex phenology and source–sink interactions. Carbon source–sink manipulations with control and two treatments (reduce source, ca. 10% mature leaf pruning; reduce sink, 10% fruitlet thinning) were conducted on 2.5-year-old field-grown P. volubilis plantation during the early-wet season in a seasonal tropical area.Results: Leaf photosynthetic rate and specific leaf area largely remained unchanged in response to defoliation or defloration. Compared with control, higher N contents on average were observed in both remaining leaves and branches of the defoliated plants, suggesting that N-mobilization was mainly due to the enhanced N uptake from soil. Carbon, but not N, is a source-driven growth process of P. volubilis plants, as defoliation reduced the contents of non-structural carbohydrates (especially sugar) in branches, although temporally, whereas defloration increased available C reserve. The seasonal dynamic pattern of fruit ripening was altered by source–sink regulations. The total seed yield throughout the growing season that depends on fruit set and retention (i.e., number of matured fruit) rather than individual fruit development (size), was slightly increased by defloration but was significantly decreased by defoliation. Compared with control, defloration did not enrich the KEGG pathway, but defoliation downregulated the TCA cycle and carbohydrate and lipid metabolisms in fruitlets after 24 days of the applications of source–sink manipulation. Conclusion: Carbohydrate reserves served to buffer sink–source imbalances that may result from temporary adjustment in demand for assimilates (e.g., defloration) or shortfalls in carbon assimilation (e.g., defoliation). Defoliation is disadvantageous for the yield and also for carbohydrate and lipid accumulation in fruits of P. volubilis plants. Although more studies are needed, these results provide new insights to the further improvement in seed yield of the strong source-limited P. volubilis plants by source/sink manipulations.

Background Chenopodium quinoa Willd., a halophytic crop, shows great variability among different genotypes in response to salt. To investigate the salinity tolerance mechanisms, five contrasting quinoa cultivars belonging to highland ecotype were compared for their seed germination (under 0, 100 and 400 mM NaCl) and seedling’s responses under five salinity levels (0, 100, 200, 300 and 400 mM NaCl). Results Substantial variations were found in plant size (biomass) and overall salinity tolerance (plant biomass in salt treatment as % of control) among the different quinoa cultivars. Plant salinity tolerance was negatively associated with plant size, especially at lower salinity levels (+ and K+) increased but K+/Na+ decreased in both leaves and roots. Across different salinity levels and cultivars, without close relationships with antioxidant enzyme activities (SOD, POD, or CAT), salinity tolerance was significantly negatively correlated with organic solute and malondialdehyde contents in leaves and inorganic ion contents in leaves or roots (except for root K+ content), but positively correlated with K+/Na+ ratio in leaves or roots. Conclusion Our results indicate that leaf osmoregulation, K+ retention, Na+ exclusion, and ion homeostasis are the main physiological mechanisms conferring salinity tolerance of these cultivars, rather than the regulations of leaf antioxidative ability. As an index of salinity tolerance, K+/Na+ ratio in leaves or roots can be used for the selective breeding of highland quinoa cultivars.

Novel branch-trunk Ag hierarchical nanostructures were fabricated by hydrothermal process combined with microwave-assisted synthesis. Te nanowires prepared by hydrothermal process were used as template. And then the branch-truck Ag hierarchical nanostructures were constructed on Te nanowires via galvanic replacement reaction with the Te nanowires as the sacrifice temple with microwave-assisted synthesis method. We further investigated the potential application of the obtained hierarchical nanostructures as sensors for the electrochemical analysis of ascorbic acid. Results showed that the as-prepared sensors had a wide linear range of 0.17 μM to 1.80 mM (R = 0.999) and a detection limit of approximately 0.06 μM (S/N = 3). These indicated that the branch-trunk Ag hierarchical nanostructures were excellent candidate materials for sensing applications.

Our understandings on the patterns and mechanisms of plant community assembly during succession, especially the primary succession in glacier retreat areas, remain limited. The Hailuogou Glacier Chronosequence provides a distinctive place to disentangle the biotic interactions and abiotic filtering effects on community successional trajectories. Through community-weighted approaches, we quantified elements allocation and regulation in leaves and roots, N:P stoichiometry, and the biotic and abiotic controls guiding community dynamics along the 120-year chronosequence. Across seven primary successional stages, plant leaves featured higher concentrations of macro-elements with lower coefficients of variation (CV) with increasing succession; whereas, fine roots contained more micro-elements with higher CV. From the early to late stages, foliar N:P increased linearly from 8.2 to 20.1. These findings highlighted that the limiting factor for plant growth shifted from N to P over one century of deglaciation. Edaphic factors (pH, bulk density, N and P concentrations) acted as deterministic filtering for trait convergence in the early stages, while biotic factors (species richness and plant litter biomass) for competitive exclusion dominated the late stages hosting species with stronger homoeostatic regulation and more conservative nutrient use.

Rosa praelucens is a critically endangered decaploid alpine rose with an extremely narrow geographic distribution in Northwestern Yunnan, China. We sampled almost all the extant individuals (527 individuals in 31 natural locations and 56 individuals preserved in three local living collections) to assess the genetic variation and to probe the genetic connectivity among the individuals and populations based on three cpDNA intergenic spacers and six fluorescent amplified fragment length polymorphism (AFLP) markers. The morphological traits from seven populations were also measured. R. praelucens exhibited high levels of morphological variation, genetic diversity, and differentiation. The extant individuals were clustered into eight groups in neighbor-net networks, and subsequent Bayesian analysis assigned them into three larger gene pools, both in accordance with their morphological traits, especially flower color. The living collections embraced two private cpDNA haplotypes and included three out of the species’ total eight AFLP genotypes. Rhizome clonal growth, decaploid, and mixed breeding system may largely contribute to high genetic diversity and differentiation in R. praelucens. We concluded that the endangered status of R. praelucens may mainly be due to habitat fragmentation and loss and inherent reproductive difficulties, rather than low genetic diversity. The populations contributing higher cpDNA genetic diversity, representing more AFLP genotypes, and encompassing private cpDNA haplotypes should be given conservation priority by creating plant-micro reserves. The living collections should also be targeted for further ex situ conservation, population recovery, and reintroduction of R. praelucens plants.

Land-use conversion affects the soil community and microbial abundance, which are essential dynamic indicators of soil quality and sustainability. However, little to no work has been performed to a...

Au nanowires synthesized via a template-assisted method using Te nanowires as templates are selected as electrode materials for detecting nitrite ions. The result is verified through a series of electrochemical measurements to demonstrate that Au nanowire-modified electrodes exhibit high catalytic activity for nitrite ions. Au nanowire-modified electrodes with a loading of 0.006 μg/mm2 achieve a relatively high catalytic current oxidation with a potential of + 0.83 V. The proposed sensor exhibits a rapid response to nitrite ions (less than 5 s), and the oxidation current shows a linear relationship (R = 0.9982) with the nitrite ions concentration ranging from 1 μM to 0.97 mM, at a detection limit of 0.2 μM (S/N = 3). The proposed sensor also demonstrates high sensitivity and excellent selectivity. This study emphasizes on the practicality of the proposed sensor in the measurement of nitrite ions in tap water and pickled food.

The effects of three types of straight chain polyols (propanetriol, butantetraol, and pentitol) and one branched chain polyols pentaerythritol as electrolyte additives on the electrochemical properties of gelled electrolyte valve-regulated lead-acid (GEL-VRLA) batteries were systematically studied. Our result shows that a moderate mechanical dispersion of fumed silica in H 2 SO 4 solution is beneficial to improve the electrochemical properties of the gelled electrolyte. Adding of straight chain polyols (propanetriol, butantetraol, and pentitol) can decrease not only the optimum dispersion time, but also the electrolyte resistance of the gel. The optimum dispersion time needed is pure (90 minutes) > adding pentitol (80 minutes) > adding butantetraol (70 minutes) > adding propanetriol (60 minutes). Furthermore, the optimum agitation time can be reduced by 88% with adding of branch chain polyols pentaerythritol. Also, the charge-transfer resistance (R ct ) of gel can be reduced by more than one order of magnitude. More important, the peak current (capacity) of the lead electrode is stable with agitation time, which is significant for practical application. The adding of pentaerythritol makes the gel more uniform and porous, demonstrating that it is a promising gel electrolyte for VRLA batteries.

A novel branch-trunk Ag hierarchical nanostructure was synthesized via a galvanic replacement reaction combined with microwave-assisted synthesis using Te nanowire as a sacrificial template. The Te nanowire was synthesized via a hydrothermal process. We further investigated the potential application of the obtained hierarchical nanostructures in electrochemical sensor analysis. The results showed that the as-prepared sensor exhibited a wide linear range with 0.05 µM to 1.925 mM (R = 0.998) and the detection limit was estimated to be 0.013 µM (S/N = 3). These results indicate the branch-truck Ag hierarchical nanostructures are an excellent candidate material for sensing applications.

A novel electrochemical sensor for the detection of formaldehyde based on palladium (Pd) nanowire (NW) arrays was developed. The Pd NW arrays were obtained via the direct electrodeposition of Pd on a glassy carbon electrode within the pores of an anodized aluminum oxide membrane. The electrocatalytic activity of the Pd NW arrays electrode for formaldehyde detection in alkaline media was then investigated via a series of electrochemical measurements; the results show the very high catalytic activity of the electrode. The formaldehyde oxidation on the Pd NW arrays electrode at +0.03 V, which is more negative than that in previous report. The experimental data further reveal that the electrooxidation of formaldehyde inhibits the formation of the poisonous intermediate, carbon monoxide. The proposed sensor has high sensitivity and fast response to formaldehyde, and the oxidation current has a linear relationship with the formaldehyde concentration in the 2 μM to 1 mM range (R = 0.9982). The detection limit was 0.5 μM (S/N = 3). The sensor has high sensitivity and good selectivity.

Highly ordered Pd nanowire arrays (NWAs) are prepared using a porous aluminum oxide template by pulse electrodeposition. The obtained Pd nanowire arrays with the diameter of 50 nm and length of 850 nm have been characterized by scanning electron microscopy, energy dispersive X-ray analysis, and high resolution transmission electron microscope. Meanwhile, the electrocatalytic activity of Pd NWAs electrodes for methanol and isopropanol oxidation in alkaline media is studied. It is found that the obtained nanostructures exhibit excellent catalytic activity for alcohol electrooxidation. The isopropanol oxidation shows the higher activity on Pd NWAs electrode than methanol in alkaline medium. Keywords: Palladium, Methanol, Isopropanol, Fuel cells, Sensor

Coffea arabica is a major economic plant in agriculture plantation in tropical and subtropical areas in the world. This paper reports the experimental results on the fertilization strategy in Yunnan, China. Effects of varied levels of nitrogen (N), phosphorus (P), potassium (K) nutrients on the growth, photosynthetic characteristics and yield in three-year old saplings of C. arabica with the density of 4500 individuals per hectare were measured. In general, N is the most important factor influencing the growth, photosynthetic capacity and yield of C. arabica, followed by K and P, respectively. The yield can be improved through spraying appropriate amount of trace elements in the leaves. The optimum matching experiments in fertilization level of N:P2O5: K2O is at the ratio of 1:0.5:1. The high yield of C. arabica need high nutrient demands, but the optimum amount of fertilizer of N, P2O5, K2O is 100, 50, 100 g per individual according to the cost-benefits analysis. The yield of C. arabica was closely related with the numbers of branch, total leaf areas and maximum rate of net photosynthesis (Amax) among different treatments. Different fertilization strategy had no significantly effects on the photochemical efficiency in dawn, but all indicators showed that the higher-fertilized plants could significantly alleviate diurnal photoinhibition.

Straw mulching and drip irrigation have been widely used for coffee production. In order to know if these techniques are suitable in Yunnan, five-year-old coffee plants were separated into 8 groups to grow in the field under 2 fertilization rates (low and high) and 4 watering regimes: dry straw mulching (M), drip irrigation (I), drip irrigation + straw mulching (MI) and control treatment (CK), and the effects of various watering and fertilization treatments on the growth and photosynthetic characteristics of Coffea arabica with the density of 4500 individuals per hectare were measured. The results showed that during one year's growth period, the coffee plants had two growth peaks, one was in May when the rainy season just begun, and the another was in August to September, the middle of rainy season. Higher fertilization promoted the relative height and length growth rates of the branches, but watering treatments hadn't significant effects on them. In dry season, watering significantly promoted the Pn, gs, Tr and WUE, while water status had no significant influence on the internal fluorescence features of PSII. In wet season, high-fertilized plants had a higher leaf nitrogen content and Pn than low-fertilized plants, and Pn was positively correlated with leaf nitrogen content. In both seasons, higher fertilization increased the WUE regardless of the watering treatments. At the same time, the high-fertilization treatment significantly alleviated diurnal photoinhibition, companying with a higher energy utilization through photochemistry and a higher energy dissipation through xanthophyll cycle, which appears that high-fertilized coffee plants have the mechanism to acclimate to strong light environment. All the results indicated that wet season is the optimum time for the photosynthesis and growth of C. arabica, and C. arabica needs a high fertilization investment and fine watering managements during its whole growth period. Among the three man-made watering treatments, MI was the best, M and I had the nearly same effects but the former was more practical than the latter.

Stomatal characteristics and its plasticity in leaves of four canopy species, Shorea chinensis, Pometia tomentosa, Anthocephalus chinensis, Calophyllun polyanthum and three middle-layer species, Barringtonia pendula, Garcinia hanburyi, Horsfieldia tetratepala acclimated to different light conditions (8%, 25%, 50% and 100% of full sunlight) for more than one year were surveyed. All plant's stomata were distributed on the abaxial of leaves. Pometia tomentosa and Barringtonia pendula had higher stomatal density, and the guard cell length of Anthocephalus chinensis and Calophyllun polyanthum were much greater than others'. Stomatal density and stomatal index (ratio of stomatal numbers to epidermal cell number) were increased with growth irradiance increased, while numbers of stomata per leaf were higher in the low than the high relative PFD, and stomatal conductance of leaves was the highest in the 50% of sunlight except for Anthocephalus chinensis. The relative PFD had little effects on the guard cell length of all seven plants. There was a significant negative correlation between stomatal density and leaf area, but the stomatal conductance was not significantly positive with the stomatal conductance in some degree. The analysis of phenotypic plasticity of stomatal characteristics showed that plasticity index for stomatal index and numbers of stomatal per leaf were similar for canopy and middle-layer species, while the plasticity index of stomatal density and stomatal conductance were significantly greater for canopy species than middle-layer species. The high plasticity of canopy species was consistent with the hypothesis that specialization in a more favorable environment increases plasticity.

The photosynthetic characteristics and protective role of leaf antioxidant systems were studied for seedlings of three woody species, Anthocephalus chinensis, Barringtonia pendala, Garcinia hanburyi, acclimated to 8%, 25%, 50% of natural sunlight for four months. As growth irradiance increased, the saturation points, the light compensation points of photosynthesis, the maximum net photosynthetic rate, and the non-photochemical quenching efficiency of three species were increased, while the apparent quantum yield (AQY), the effective quantum efficiency (Fv'/Fm'), and the photochemical quenching efficiency (qP) were decreased. In protective enzymes systems, SOD and APX activities increased with increasing growth irradiance, but CAT activity was not consistent with PFD. AsA exhibited the most dramatic increase in response to growth irradiance. It could be concluded that besides the increase in xanthophyll cycle-dependent energy dissipation, the enhancement of leaf antioxidants was also a protective pathway against high light intensity.