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BACKGROUND: MicroRNAs (miRNAs) play a key role in various biological processes by influencing the translation of target messenger RNAs (mRNAs) through post‐transcriptional regulation. The miR‐184‐3p has been identified as an abundant conserved miRNA in insects. However, less is known about its functions in insect–plant virus interactions. RESULTS: The function of miR‐184‐3p in regulation of plant viral infection in insects was investigated using a rice black‐streaked dwarf virus (RBSDV) and Laodelphax striatellus (Fallén) interaction system. We found that the expression of miR‐184‐3p increased in L. striatellus after RBSDV infection. Injection of miR‐184‐3p mimics increased RBSDV accumulation, while treatment with miR‐184‐3p antagomirs inhibits the viral accumulation in L. striatellus. Ken, a zinc finger protein, was identified as a target of miR‐184‐3p. Knockdown of Ken increased the virus accumulation and promoted RBSDV transmission by L. striatellus. CONCLUSION: This study demonstrates that RBSDV infection induces the expression of miR‐184‐3p in its insect vector L. striatellus. The miR‐184‐3p targets Ken to promote RBSDV accumulation and transmission. These findings provide a new insight into the function of the miRNAs in regulating plant viral infection in its insect vector. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are non-coding RNAs, which, as members of the RNA interference pathway, play a pivotal role in antiviral infection. Almost 80% of plant viruses are transmitted by insect vectors; however, little is known about the interaction of the miRNAs of insect vectors with plant viruses. Here, we took rice black-streaked dwarf virus (RBSDV), a devastating virus to rice production in eastern Asia, and the small brown planthopper, (SBPH, Laodelphax striatellus) as a model to investigate the role of microRNA750-3p (miR750-3p) in regulating viral transmission. Our results showed that Ls-miR750-3p was downregulated in RBSDV-infected SBPH and predominately expressed in the midgut of SBPH. Injection with miR750-3p agomir significantly reduced viral accumulation, and the injection with the miR750-3p inhibitor, antagomir-750-3p, dramatically promoted the viral accumulation in SBPH, as detected using RT-qPCR and Western blotting. The processing of precursor 7 (POP7), a subunit of RNase P and RNase MRP, was screened, identified, and verified using a dual luciferase reporter assay as one target of miR750-3p. Knockdown of POP7 notably increased RBSDV viral propagation in SBPH and then increased the viral transmission rate by SBPH. Taken together, our data indicate that miR750-3p targets POP7 to suppress RBSDV infection in its insect vector. These results enriched the role of POP7 in modulating virus infection in host insects and shared new insight into the function of miRNAs in plant virus and insect vector interaction. [ABSTRACT FROM AUTHOR]

Both microbes and plants contribute to soil organic carbon (SOC) formation and retention, but their roles in controlling SOC dynamics in forest soils under Moso bamboo (Phyllostachys edulis) expansion remain unclear. Here, amino sugars and lignin monomers were measured to represent microbial necromass and plant‐derived components, respectively. The observed decline in both amino sugars and lignin monomers during Moso bamboo expansion indicates a reduction in microbial necromass and recalcitrant plant contributions to SOC composition. This could be attributed to a limitation of microbial substrates and proliferation caused by the reduced litter inputs resulting from the expansion. The proportion of microbial necromass contributing to the SOC pool increased, but that of lignin monomers decreased, as SOC content decreased with Moso bamboo expansion. This suggests that the decrease of SOC during bamboo expansion was mainly due to the reduction of lignin, while the increased contribution of microbial‐derived carbon to SOC may serve to improve SOC stability. Our study sheds light on the altered SOC source inputs resulting from Moso bamboo expansion and emphasizes the need for sustainable forestry management practices that differentiate between microbial‐ and plant‐derived carbon pools. [ABSTRACT FROM AUTHOR]

Hosts can initiate macroautophagy/autophagy as an antiviral defense response, while viruses have developed multiple ways to evade the host autophagic degradation. However, little is known as to whether viruses can target lipids to subvert autophagic degradation. Here, we show that a low abundant signaling lipid, phosphatidylinositol 3,5-bisphosphate (PtdIns(3,5)P2), is required for rice black-streaked dwarf virus (RBSDV) to evade the autophagic degradation in the insect vector Laodelphax striatellus. RBSDV binds to PtdIns(3,5)P2 and elevates its level through its main capsid protein P10, leading to inhibited autophagy and promoted virus propagation. Furthermore, we show that PtdIns(3,5)P2 inhibits the autophagy pathway by preventing the fusion of autophagosomes and lysosomes through activation of Trpml (transient receptor potential cation channel, mucolipin), an effector of PtdIns(3,5)P2. These findings uncover a strategy whereby a plant virus hijacks PtdIns(3,5)P2 via its viral capsid protein to evade autophagic degradation and promote its survival in insects. [ABSTRACT FROM AUTHOR]

Purpose: The fixation of atmospheric CO2 and N2 by soil bacteria is important to the terrestrial carbon and nitrogen cycles and can be greatly affected by anthropogenic disturbance. The application of mineral fertilizer combined with manure (MCM) has been used to maintain soil quality and improve soil C storage. However, the impacts of MCM on soil CO2-fixing bacteria (CFB) and N2-fixing bacteria (NFB), encoded separately by the cbbL and nifH genes, remain largely unknown. Methods: In this study, we examined how the community structure of soil CFB and NFB from a chronosequence of Moso bamboo forests (6, 10, 15, and 20 years of intensive management) responded to long-term intensive management with MCM and identified the critical determinants that regulated them. Quantitative PCR and high-throughput pyrosequencing of the cbbL and nifH genes were used to analyze the abundance and community composition of CFB and NFB, respectively. Results: Employing MCM enhanced the content of SOC and soil available N, K, although some fluctuating values were observed over the 20-year period. The abundance of cbbL gene decreased significantly (P < 0.05) after 6 years of management and then recovered after 20 years of management. However, the abundance of nifH gene consistently declined over 20 years of management. The diversity of CFB increased significantly after 6 years of management, while that of NFB decreased significantly after 15 years of management compared to the no-fertilizer control. The phylum Proteobacteria was predominant in the CFB and NFB communities. Furthermore, the sum abundance of keystone taxa Rhodopseudomonas, Aminobacter, and Rubrivivax for CFB increased after 20 years of management, while the keystone taxon Bradyrhizobium for NFB decreased after 20 years of management compared to no-fertilizer control. Conclusions: In conclusion, the application of MCM favors the abundance, diversity, and keystone taxa of soil CFB rather NFB, which may improve soil C fixation. [ABSTRACT FROM AUTHOR]

Soil extracellular enzyme activities among aggregate fractions are critical to short-term microbial activity and long–term carbon dynamics in forest ecosystems, but little is known regarding the effects of forest types on the soil enzyme activities in different soil aggregate fractions. Three typical subtropical forest types (Broadleaved forest, Moso bamboo forest and Chinese fir forest) were selected, and undisturbed soil samples (0–15 cm) were collected. We investigated the effects of forest types on aggregate stability (mean weight diameter, geometric mean diameter and fractal dimension), aggregate–associated organic carbon (OC) and the functionality of five enzymes (cellobiohydrolase, β-glucosidase, β-xylosidase, N–acetylglucosaminidase, leucine aminopeptidase) of different aggregate fractions (>2 mm, 0.25–2 mm, 0.053–0.25 mm and <0.053 mm). The results showed that the proportion of macro-aggregates, aggregate stability and macro–aggregates associated–carbon content and storage were higher in broadleaved and Moso bamboo forests than in Chinese fir forests, indicating that forest types influence the distribution of total soil OC among aggregate fraction classes and would delay the loss of OC in broadleaved and Moso bamboo forests. We also found that the extracellular enzymes were higher in aggregates of broadleaved forests and Moso bamboo forests. SEM (structural equation model) analysis also supported significantly positive relationships between litter quantity and aggregate enzyme activity, and indirect impact of litter quantity and litter C/N ratio together with soil organic carbon (SOC) and soil aggregate organic C content (SAOCC) on aggregate enzyme activity. The results of this study indicate that forest types showed large impact on aggregate-associated OC and enzyme activities, and the litter input of different forest types is the main control on enzyme activity among different aggregate fractions, and thus may play an important role in adjusting the sink capacity and stability of SOC. [ABSTRACT FROM AUTHOR]

Aims: Invasive plants not only alter aboveground biodiversity but also belowground microbial community composition to facilitate their growth and competitiveness. However, how plant invasion affects soil microbial resource limitation and metabolic activity, and their linkages with litter and soil stoichiometries remain largely unknown. Methods: We investigated the carbon (C): nitrogen (N): phosphorus (P) stoichiometries of litter, soil, microbe and extracellular enzymes, composition of main microbial groups and substrate utilization rate in a subtropical forest invaded by Moso bamboo (Phyllostachys edulis) and those in adjacent broadleaf and mixed bamboo-broadleaf forests. Results: Bamboo invasion significantly decreased annual litter production, litter C: P and N: P ratios, and soil C:N and C:P ratios, whereas increased microbial biomass C:N and C:P ratios, resulting in decreased C:N and C:P imbalances between soil microorganisms and their resources. Bamboo invasion decreased the N and P acquiring enzymes activities, mitigated the status of microbial N and P limitation as indicated by enzymatic stoichiometry, and caused a higher C use efficiency. Soil microbial community structure was shifted towards a lower fungi: bacteria (F:B) ratio in bamboo forest. Bamboo forest soil showed a lower capacity of microbes to use N-rich resources in comparison to C-rich resources. Structural equation modeling suggested a direct and negative effect of C:N imbalance on microbial N limitation and metabolic capacity. Conclusions: This study suggests the importance of stoichiometric imbalance between decomposers and their resources in regulating soil microbial community structure and enzyme activities following plant invasion. [ABSTRACT FROM AUTHOR]

A field experiment was carried out to study the responses of soil respiration, soil C and N, composition of main microbial groups, enzyme activity, and microbial C source utilization to two organic amendments (i.e., straw and manure) added alone or combined with biochar for 9 months in an infertile soil. In comparison with the non-amended control, soil CO2 emission rates were significantly increased following straw and manure addition, but they were decreased by 19% and 36% on average when co-applied with biochar. Organic amendments significantly increased the size of labile C pool by 21%, total phospholipid-fatty acid (PLFA) concentrations by 32%, activities of α-glucosidase by 51%, β-glucosidase by 115%, β-D-cellobiosidase by 105%, β-xylosidase by 43%, phenol oxidase by 59%, and peroxidase by 91% on average relative to the non-amended control, whereas biochar co-application with organic amendments had no effect on soil PLFA concentrations but significantly decreased the enzyme activities by 38% and the sizes of labile C and N pools by 16% on average. The results of the substrate-induced respiration confirmed a lower capacity of biochar-treated soils to use the C sources of carbohydrates and carboxylic acids. Structural equation modeling indicated that the response of soil CO2 emission rates to organic amendment and biochar was directly linked to their effects on microbial activities. Therefore, our study demonstrated that biochar co-applied with straw or manure mitigated soil C loss by decreasing soil microbial activities. [ABSTRACT FROM AUTHOR]

BACKGROUND: MicroRNAs (miRNAs), a class of small non‐coding endogenous RNAs, play key roles in various biological processes. Most plant viruses are transmitted by insect vectors. However, little is known about the function of miRNAs on plant virus‐insect host interaction. RESULTS: We investigated the role of miR‐315‐5p in regulation of plant viral infection in insects using a rice black‐streaked dwarf virus (RBSDV) and small brown planthopper (SBPH) interaction system. Our results showed that miR‐315‐5p had the highest expression level in 2nd‐instar nymph, and was highly expressed in the salivary gland and midgut in SBPH. miR‐315‐5p was in response to and regulated RBSDV infection in SBPH. Injection of miR‐315‐5p mimic, agomir‐315, significantly increased the RBSDV accumulation, whereas injection of miR‐315‐5p inhibitor, antagomir‐315, reduced virus accumulation in SBPH. Furthermore, a melatonin receptor was identified as a target gene of miR‐315‐5p by the dual luciferase reporter assay. Knockdown of the melatonin receptor significantly increased the expression of RBSDV coat protein gene S10 and replication related genes, S5‐1, S6, and S9‐1. Furthermore, treatment with melatonin receptor antagonist luzindole and activator agomelatine significantly increased and reduced RBSDV accumulation in SBPH, respectively. Compared to the control, miR‐315‐5p did not affect the efficiency of RBSDV acquisition in SBPH. However, the efficiency of RBSDV transmission was significantly reduced after injecting antagomir‐315. CONCLUSION: Taken together, our data reveal that miR‐315‐5p is beneficial for RBSDV infection in its insect vector by directly targeting a melatonin receptor. These findings provide a new insight to the function of miRNAs in virus‐insect vector interaction. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) are endogenous RNAs that have critical regulatory roles in numerous biological processes. However, it remains largely unknown whether circRNAs are induced in response to plant virus infection in the insect vector of the virus as well as whether the circRNAs regulate virus infection. Rice black-streaked dwarf virus (RBSDV) is transmitted by Laodelphax striatellus (Fallén) in a persistent propagative manner and causes severe losses in East Asian countries. To explore the expression and function of circRNAs in the regulation of virus infection, we determined the circRNA expression profile in RBSDV-free or RBSDV-infected L. striatellus midgut tissues by RNA-Seq. A total of 2,523 circRNAs were identified, of which thirteen circRNAs were differentially expressed after RBSDV infection. The functions of these differentially circRNAs were predicted by GO and KEGG pathway analyses. The expression changes of five differentially expressed circRNAs and eight parental genes were validated by RT-qPCR. The circRNAs-microRNAs (miRNAs) interaction networks were analyzed and two miRNAs, which were predicted to bind circRNAs, were differentially expressed after virus infection. CircRNA2030 was up-regulated after RBSDV infection in L. striatellus midgut. Knockdown of circRNA2030 by RNA interference inhibited the expression of its predicted parental gene phospholipid-transporting ATPase (PTA) and enhanced RBSDV infection in L. striatellus. However, none of the six miRNAs predicting to bind circRNA2030 was up-regulated after circRNA2030 knockdown. The results suggested that circRNA2030 might affect RBSDV infection via regulating PTA. Our results reveal the expression profile of circRNAs in L. striatellus midgut and provide new insight into the roles of circRNAs in virus–insect vector interaction. [ABSTRACT FROM AUTHOR]

The role of soil organic C (SOC) quality affecting microbial community composition and function under biochar application is poorly understood. We investigated the relationship between the pool size and chemical composition of SOC; composition of main microbial groups; enzyme activities involved in C, N, and P cycling; and soil respiration in a rice paddy amended with biochar for 20 months in a laboratory experiment at 15, 25, and 35 °C. Soil labile and recalcitrant organic C pools were determined by a two-step sulfuric acid (H2SO4) hydrolysis method. The chemical composition of SOC was determined with 13C-nuclear magnetic resonance spectroscopy. The biochar amendment at 20 and 40 t ha−1 significantly decreased the soil labile C pool I (extracted by 5 N H2SO4), alkyl, and carbonyl C contents and increased the recalcitrant C pool (acid-resistant) and aromatic C contents and the aromatic C to O-alkyl C ratio. The phospholipid-fatty acid concentrations and soil enzyme activities were unchanged by biochar application at 10 and 20 t ha−1, but both were increased at 40 t ha−1. Biochar increased the ratio of gram-positive (G+) to gram-negative (G−) bacteria and decreased that of fungi to bacteria. The recalcitrant C pool and aromatic C contents were positively correlated to the G+ bacteria abundance and were important factors in shaping composition of the main microbial groups and improving enzyme activities. Biochar application at 40 t ha−1 lowered soil respiration rates at 15 and 25 °C by decreasing labile C pool and increasing C recalcitrancy while increased temperature sensitivities of soil respiration at 25/15 °C and 35/25 °C by stimulating microbial abundance and enzyme activities. Together, our results suggest that biochar soil amendment shifted microbial community composition and function through influencing the composition of SOC. [ABSTRACT FROM AUTHOR]

Aims: Plant invasion can alter the soil microbial community and carbon cycling in terrestrial ecosystems; however, shifts in soil autotrophic bacterial communities and their driving environmental factors after plant invasion remain largely unknown. This study examined the relationship between Moso bamboo (Phyllostachys pubscens) invasion into broadleaf forests and autotrophic bacterial community composition-function at two field sites.Methods: The abundance and composition of autotrophic bacteria were characterized by real-time PCR, terminal restriction fragment length polymorphism, and clone library based on the cbbL gene that encodes ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO).Results: On average, the cbbL gene abundance was 89% higher and RubisCO enzyme activity 110% higher in the bamboo forest than in the broadleaf forests across the two field sites. The cbbL gene abundance was positively correlated with the RubisCO enzyme activity. The cbbL-containing communities were dominated by the order Rhizobiales, and their composition differed between the forest types and between the two sites, with the effect of site location being greater. Soil readily-oxidizable carbon concentration was a critical factor determining the site location effect on the diversity and activity of the cbbL-containing community.Conclusion: Greater abundance and activity of autotrophic bacteria were associated with bamboo invasion into broadleaf forests, implying that such invasions are expected to increase the CO2 fixation potential. [ABSTRACT FROM AUTHOR]

RNA interference (RNAi) is a conserved mechanism against viruses in plants and animals. It is thought to inactivate the viral genome by producing virus‐derived small interfering RNAs (vsiRNAs). Rice black‐streaked dwarf virus (RBSDV) is transmitted to plants by the small brown planthopper (Laodelphax striatellus), and seriously threatens production of rice in East Asia, particularly Oryza sativa japonica subspecies. Through deep sequencing, genome‐wide comparisons of RBSDV‐derived vsiRNAs were made between the japonica variety Nipponbare, and the indica variety 9311. Four small RNA libraries were constructed from the leaves and shoots of each variety. We found 659,756 unique vsiRNAs in the four samples, and only 43,485 reads were commonly shared. The size distributions of vsiRNAs were mostly 21‐ and 22‐nt long, and A/U bias (66‐68%) existed at the first nucleotide of vsiRNAs. Additionally, vsiRNAs were continuously but heterogeneously distributed along S1‐S10 segments of the RBSDV genome. Distribution profiles of vsiRNA hotspots were similar in different hosts and tissues, and the 5′‐ and 3′‐terminal regions of S4, S5, and S8 had more hotspots. Distribution and abundance of RBSDV vsiRNAs could be useful in designing efficient targets for exploiting RNA interference for virus resistance. Degradome analysis found 25 and 11 host genes appeared to be targeted by vsiRNAs in 9311 and Nipponbare. We report for the first time vsiRNAs derived from RBSDV‐infected rice. [ABSTRACT FROM AUTHOR]

Aims: Moso bamboo ( Phyllostachys pubescens) is a fast-growing species that can invade neighboring forests through its vigorous rhizome system, leading to large shifts of plant diversity and soil properties. A primary concern is the response of arbuscular mycorrhizal fungal (AMF) communities and related soil C sequestration to bamboo forest expansion. Methods: We used a long-term soil chronosequence from primary broadleaved forest to moso bamboo forest to examine the changes in AMF abundance and communities, as well as their role in soil C storage. Results: AMF communities showed strong niche differentiation, and were highly structured by forest type ( r = 0.648, P = 0.001), and marginally correlated to soil pH and organic C. Bamboo forest expansion increased soil AMF biomass as indicated by neutral lipid fatty acids (NLFA) 16:1ω5 abundance, easily extracted glomalin-related soil protein (EE-GRSP), and water-stable macroaggregates. We observed that soil AMF biomass contributed substantially to both soil macroaggregates and EE-GRSP, which were tightly correlated with soil organic C. The influence of bamboo forest expansion on soil C sequestration was mainly due to its indirect effect on AMF biomass. Conclusions: Bamboo forest expansion significantly changed soil AMF communities and increased AMF biomass, which in turn contributed to enhanced soil aggregation and C storage. [ABSTRACT FROM AUTHOR]

Aims: Soil fungi play an important role in decomposing soil organic matter and facilitating nutrient uptake by plants, however, the relationship between fungal community and soil biogeochemical cycling during plant invasion is poorly understood. The objective of this study was to investigate the effects of Moso bamboo ( Phyllostachys edulis) invasion into broadleaf forests on the soil organic C (SOC) chemical composition, fungal community and mineral N production. Methods: We collected soil samples in evergreen broadleaf forests, mixed bamboo-broadleaf forests and bamboo forests. Soil fungal community and SOC chemical composition were determined. Results: Bamboo invasion decreased alkyl C but increased O-alkyl C contents. Soil fungal abundance (18S rRNA) was decreased, while their alpha diversity was increased by bamboo invasion. Additionally, bamboo invasion enhanced net N mineralization rate but reduced gross nitrification rate. The fungal community composition strongly correlated with alkyl C content, and alkyl C content explained 32% of the variation in the fungal abundance. Fungal community composition correlated with gross nitrification rate, with 43% of the variation in gross nitrification rate attributable to soil fungal abundance. Conclusions: Changes in soil fungal community caused by bamboo invasion into broadleaf forests were closely linked to changed soil organic C chemical composition and decelerated nitrate production. [ABSTRACT FROM AUTHOR]

Systemic acquired resistance, mediated by the Arabidopsis NPR1 gene and the rice NH1 gene, confers broad-spectrum immunity to diverse pathogens. NPR1 and NH1 interact with TGA transcription factors to activate downstream defense genes. Despite the importance of this defense response, the signaling components downstream of NPR1/NH1 and TGA proteins are poorly defined. Here we report the identification of a rice mutant, snim1, which suppresses NH1-mediated immunity and demonstrate that two genes encoding previously uncharacterized cysteine-rich-receptor-like kinases (CRK6 and CRK10), complement the snim1 mutant phenotype. Silencing of CRK6 and CRK10 genes individually in the parental genetic background recreates the snim1 phenotype. We identified a rice mutant in the Kitaake genetic background with a frameshift mutation in crk10; this mutant also displays a compromised immune response highlighting the important role of crk10. We also show that elevated levels of NH1 expression lead to enhanced CRK10 expression and that the rice TGA2.1 protein binds to the CRK10 promoter. These experiments demonstrate a requirement for CRKs in NH1-mediated immunity and establish a molecular link between NH1 and induction of CRK10 expression. [ABSTRACT FROM AUTHOR]

Ahigh-throughput, specific, and rapid liquid chromatography with tandem mass spectrometrymethod was established and validated for the simultaneous determination of atorvastatin and its two major metabolites, ortho-hydroxyatorvastatin and para-hydroxyatorvastatin, in human plasma. A simple salting-out-assisted liquid–liquid extraction using acetonitrile and a mass-spectrometry-friendly salt, ammonium acetate, was employed to extract the analytes from human plasma. A recovery of more than 81% for all analytes was achieved in 1 min extraction time. Chromatographic separation was performed on a Kinetex XB C18 column utilizing a gradient elution starting with a 60% of water solution (1% formic acid), followed by increasing percentages of acetonitrile. Analytes were detected on a tandem mass spectrometer equipped with an electrospray ionization source that was operated in the positive mode, using the transitions of m/z 559.3 → m/z 440.2 for atorvastatin, and m/z 575.3 → m/z 440.2 for both ortho- and para-hydroxyatorvastatin.Deuterium-labeled compounds were used as the internal standards. The method was validated over the concentration ranges of 0.0200–15.0 ng/mL for atorvastatin and ortho-hydroxyatorvastatin, and 0.0100–2.00 ng/mL for para-hydroxyatorvastatin with acceptable accuracy and precision. It was then successfully applied in a bioequivalence study of atorvastatin. [ABSTRACT FROM AUTHOR]

The results of a three-year field experiment showed that boron application significantly increased spring shoot length, spring shoot incidence, leaf area, and uptake of N, P, and K in red bayberry (Myrica rubra Sieb.et Zuca). Soil application of boron gave a significantly higher fruit yield than foliar application of boron in 2009 and 2008. On average, over three years the increases in uptake amounts of N, P, and K as well as fruit yield were in the following order: soil application of boron every year > foliar B application every year > soil B application only in the first year > foliar B application only in the first year. [ABSTRACT FROM AUTHOR]

Rice black-streaked dwarf virus (RBSDV), a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén). RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE) were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways. [ABSTRACT FROM AUTHOR]

As a part of the Long-term Urban Ecosystem Observation and Research Station in Xiamen (Xiamen LUEORS) with the Environmental Internet of Things (EIoT) as its technical support, southeast China by the Institute of Urban Environment, Chinese Academy of Sciences, long-term monitoring was established in an urbanizing watershed to understand the effects of urbanization on stream water quality. Six monitoring sites were established within forested headwater (Headwater), reservoir (Reservoir), agricultural (Agriculture, two locations), suburban residential (Residence), and estuarine (Estuary) locations within the Bantou reservoir watershed. Results from data collected in the whole year of 2012 show that in-stream total dissolved nitrogen (TDN) concentrations were significantly higher in the agricultural and residential sites and in the cool season. Although dissolved inorganic nitrogen (DIN) in stream water was dominated by-N rather than-N except in the headwater and estuary sites,-N concentrations were relatively greater in the residential and two agricultural sites than other sites. Dissolved organic nitrogen (DON) in stream water was high, comprising more than half of TDN in the forested headwater and estuary sites and nearly one third of TDN in other sites. Rain events (rainfall on or between the sampling dates) did not significantly influence nitrogen concentrations in stream water. Surface sediments from the different sites had similar denitrification enzyme activity (DEA), comparable to previous studies. Potential nitrification (potential ammonium oxidation, PAO) was significantly greater in the agricultural and residential sites (P < 0.05). These preliminary results suggest that land-use change has significant effects on watershed nitrogen dynamics in southeast China and that these effects differ somewhat from results observed in other parts of the world. The difference might be due to the ‘real’ urbanizing watershed in comparison with the stabilized watersheds with little development in the developed countries. [ABSTRACT FROM AUTHOR]

Mao bamboo (Phyllostachys pubescens) with a high production and wide utilization has been planted in large scale in southern China, but little information about bamboo nutrition is available. The objective of this study was to reveal the dynamics of nutrition with growing time and the distribution of nutrition in different organs. It was found that the nutrition concentration of the whole plant generally declined with time during the period of 1-6 weeks owing to a dilution effect with the result of quickly increasing the biomass. The leaf concentration of nitrogen (N), phosphorus (P), and potassium (K) changed regularly with high concentrations observed at age 1, 2, 4, and 6, and lower at age 3 and 5. While the concentration of N, P, and K in the branch and stem generally declined with the weeks, a rapid decrease occurred from weeks 1 to 2. The concentrations of calcium (Ca) and magnesium (Mg) in bamboo leaf, branch, and stem appeared to be opposite to those of N, P, and K in corresponding plant parts. The elemental concentrations were greater (P < 0.05) in the leaves than in the branches and stems, while the storage of nutrition was greater (P < 0.05) in stem than in leaves and branch. A relative large total storage of nutrition, except P and Mg, were found in bamboo under an intensive management (IM) stand than those under extensive management (EM) stand. The total storage of different nutritions in the above-ground parts was in the order: K (243.0-285.6 kg ha-1) > N (154.5-207.8 kg ha-1) > P (10.4-12.2 kg ha-1). The nutrition stored in the bamboo plant would be removed away from the soil in every other year by the means of harvest of the bamboo trunk which is the largest nutrition pool of the bamboo plant. Therefore, supplementary nutrients, especially N and K, are strongly recommended in order to keep the productivity of bamboo. [ABSTRACT FROM AUTHOR]

Forest ecosystem succession plays an important role in soil microbiota variation, and soil microbes will re-establish ecosystem function after disturbance events. A distinctive disturbance of the expansion of bamboo forest into the surrounding broadleaved ecosystem is the change in litter type input. We conducted a 6-month microcosm experiment to examine the effects of proportional changes in leaf litter composition due to moso bamboo (Phyllostachys edulis) invasion into a broadleaved forest on soil microbial community. A series of mixed litters were prepared with bamboo litter occupying at 0%, 33%, 50%, 67% and 100% in proportion (with a decrease in litter carbon (C)/nitrogen (N) from 36.23 to 31.35), and they were then amended into a broadleaved forest soil at a rate of 1%, respectively. Soil bacterial and fungal communities at different incubation stages were determined by high-throughput sequencing. With the increasing proportion of bamboo litter, the broadleaved forest soil exhibited strong changes in microbiome assembly, including reducing bacteria alpha-diversity, the relative abundance of Acidobacteria and Basidiomycota, while increasing the relative abundance of Actinbacteria, Proteobacteria and Ascomycota. Moreover, the increased proportion of bamboo litter (0% PP→100% PP) increased the relative abundance of membrane transport and carbohydrate metabolism of soil bacteria but decreased the relative abundance of saprotrophic soil fungi. Redundancy analysis showed that bacteria rather than fungal communities changed greatly during incubation (p < 0.05). Additionally, the activities of soil pH, NO3−-N, NH4+-N, dissolved nitrogen and C- and N- acquiring enzymes were the main factors affecting bacterial and fungal community structure (p < 0.05). The soil physicochemical properties were significantly correlated with the composition of microbial phyla among different litter amendment treatments. These results indicated that different proportions of bamboo litter dramatically alter the soil bacterial rather than the fungal community, most likely by changing edaphic patterns. This study has important implications for understanding the litter–soil–microbe synergy during the bamboo forest expansion and provides a basis for assessing the ecological risk of bamboo forest expansion. [ABSTRACT FROM AUTHOR]

Simple Summary: The small brown planthopper Laodelphax striatellus is a destructive pest of rice, maize and wheat crops in Asia, causing damage by directly sucking phloem sap and transmitting plant viruses, and thus seriously impacting crops yields. Transient receptor potential mucolipin (TRPML) protein plays a vital role in Ca2+ ions release, resulting in membrane trafficking, autophagy and ion homeostasis; however, till now, we have learned little about the TRPML protein of agricultural pests. In this study, we first identified the TRPML of L. striatellus. We analyzed not only the gene evolutionary features and expression profiles but also clarified the protein subcellular localization and lipid-binding characteristics of Ls-TRPML. We found that TRPML is evolutionarily conserved among agricultural pests. Ls-TRPML is predominately expressed in L. striatellus ovary. Moreover, we found that Ls-TRPML localizes in the nuclear membrane in Spodoptera frugiperda cells and the intestine and ovary of L. striatellus. The binding of Ls-TRPML with lipids was detected by lipid-binding assay, indicating the potential role of Ls-TRPML in lipid interaction. Thus, our findings first helped us analyze the gene characterization of Ls-TRPML and then identify the binding of Ls-TRPML with lipids; our findings will broaden our understanding of TRPML's roles in agricultural pests. Transient receptor potential mucolipin (TRPML) protein in flies plays a pivotal role in Ca2+ ions release, resulting in membrane trafficking, autophagy and ion homeostasis. However, to date, the characterization of TRPML in agricultural pests remains unknown. Here, we firstly reported the TRPML of a destructive pest of gramineous crops, Laodelphax striatellus. The L. striatellus TRPML (Ls-TRPML) has a 1818 bp open reading frame, encoding 605 amino acid. TRPML in agricultural pests is evolutionarily conserved, and the expression of Ls-TRPML is predominately higher in the ovary than in other organs of L. striatellus at the transcript and protein level. The Bac–Bac system showed that Ls-TRPML localized in the plasma membrane, nuclear membrane and nucleus and co-localized with lysosome in Spodoptera frugiperda cells. The immunofluorescence microscopy analysis showed that Ls-TRPML localized in the cytoplasm and around the nuclei of the intestine cells or ovary follicular cells of L. striatellus. The results from the lipid-binding assay revealed that Ls-TRPML strongly bound to phosphatidylinositol-3,5-bisphosphate, as compared with other phosphoinositides. Overall, our results helped is identify and characterize the TRPML protein of L. striatellus, shedding light on the function of TRPML in multiple cellular processes in agricultural pests. [ABSTRACT FROM AUTHOR]

Laboratory experiments were conducted to determine the influence of three types of decomposing fresh organic materials [pig manure (PM), Astagalus sinicus (AS), and Alternanthera philoxeroides (AP)] on dissolution of Fe2O3 and ZnO and also the use of a loamy calcareous soil as an alternative source of iron (Fe) and zinc (Zn). Levels of Fe and Zn concentrations in composting solutions changed with composting time. The maximum levels of solution Fe resulting from the decomposition of the three organic materials were 20, 612, and 348 mg L-1 for PM, AS, and AP, respectively, when the soil was supplied as the Fe source, and 17, 32, and 16 mg L-1 when Fe2O3 was supplied as the Fe source. Corresponding maximum levels of solution Zn were 0.9, 0.7, and 1.3 mg L-1 and 35, 171, and 103 mg L-1 when the soil and ZnO was supplied as the Zn source respectively for the same three organic materials. [ABSTRACT FROM AUTHOR]

Oilseed rape (Brassica napus) is sensitive to low boron (B) supply, and its growth response to B may be influenced by soil temperature. To test the relationship between B and temperature, oilseed rape (cv. Hyola 42) seedlings were grown at 10°C (low) root zone temperature (RZT) with B supply from deficient to adequate B levels until growth of low B plants just began to slow down. Half of the pots were then transferred to 20°C (warm) RZT for 11 days before they were moved back to 10°C RZT for the final 4 days. Both plant dry mass and B uptake increased after plants were exposed to warm RZT. However, plant B deficiency was exacerbated by warm RZT in low B plants because of increased relative growth rate and shoot–root ratio without a commensurate increase in B uptake rate. It is concluded that RZT above the critical threshold for chilling injury in oilseed rape can nevertheless affect the incidence of B deficiency by altering shoot–root ratio and hence the balance between shoot B demand and B uptake. [ABSTRACT FROM AUTHOR]

Soil microorganisms drive nutrients cycling to a great extent, and they play an essential role in maintaining a stable soil ecosystem and ensuring sustainable forestry development. Land management has been proven to be a real factor in influencing soil quality. The purpose of this study was to investigate the effects of different land management techniques on soil microbial communities. There were four types of land management systems selected for this study: natural masson pine, Phyllostachy pubescens, Phyllostachys praecox, and vegetable. Soils were sampled from these four systems and assayed for soil microbial biomass carbon (MBC), community level substrate utilization pattern, functional diversity, and principle component analysis. Values of MBC were significantly different (P<0.05) from one another in the order of masson pine>Phyllostachy pubescens>Phyllostachys Praecox>vegetable. Analysis of community level substrate utilization pattern indicated that carbon source utilization and total activity by soil microorganisms were greater under the masson pine system than the other three systems (P<0.01). The functional diversities of soil microbial communities characterized as Shannon and McIntosh indexes were much richer in soil under masson pine system; Shannon index was 4.483, 4.241, 4.224, and 3.938 and McIntosh index was 13.51, 7.332, 6.272, and 6.261 for natural masson pine, Phyllostachy pubescens. Phyllostachys praecox, and vegetable systems, respectively. The results from the principle components analysis (PCA), based on the data of optical density (OD) at 120 h of incubation, showed that the value of the first principal component (PC1) of soil for natural masson pine was greater (P<0.05) than those for the other three systems. The difference in scores of the second principal component (PC2) between Phyllostachy pubescens, Phyllostachys praecox, and vegetable were not statistically different. The size and activity of soil microbial communities generally decreased with soil depth, with significant differences in soil MBC, community level substrate utilization pattern, and functional diversity indexes found between A and C horizons (P<0.01). It was concluded that land management systems had a great influence on soil microbial biomass, activity, and functional diversity. [ABSTRACT FROM AUTHOR]

in order to understand the behavior of water soluble organic matter (WSOM) in soil under different types of forest, soil samples from twenty sites were sampled and analyzed for each forest in the area of Huzhou, China. Each sample was extracted with both cool water (25°C) and hot water (100°C). Without exception, hot water soluble organic carbon (HWSOC) was more than cool water soluble organic carbon (CWSOC). Chinese fir forest soil contained 1.49 times more CWSOC and 1.34 times more HWSOC than did the masson pine forest soil. The CWSOC and HWSOC in soil under Chinese fir forest account for 1.11% and 1.60% of total soil organic carbon (TSOC), and 0.70% and 1.19% under masson pine forest soil, respectively. CWSOC under Chinese fir forest was closely related to SOM and microbial biomass carbon (MBC) (correlation coefficients were 0.474* and 0.482* respectively), HWSOC, however, has little to do with SOM, MBC and soil enzymatic activities. HWSOC under masson pine forest was generally associated with SOM, MBC and sucrase, urease and protease (correlation coefficients were 0.511*, 0.510*, 0.541*, 0.418*, 0.356, respectively), but CWSOC was only closely related to sucrase (0.560*) and protease (0.581**). it is concluded that higher amount of WSOC under Chinese fir forest is not good for soil chemical and biological properties. [ABSTRACT FROM AUTHOR]

Phyllostachy praecox is a major bamboo species which produces a small-type of bamboo shoot, one of the most delicious forest vegetables in China. Emergence of bamboo shoots of Phyllostachy praecox usually begins in late January to early February but most shooting does not occur until March. Mulching in winter is commonly adopted to achieve earlier emergence of the bamboo shoots. However, with mulching the plantation of bamboo trees appears to develop early senescence. This could be a result from "disordered" changes of soil chemical and/or biochemical properties. A field experiment was conducted to understand the mechanism. Three commonly used mulching materials, rice straw (RS), mixture of rice straw and rice grain hulls (RH) and leaves of bamboo trees (BL) were applied in December. A control plot without covering (CK), was also established. Dynamic changes of soil chemical properties and soil enzymatic activities were monitored through winter to spring by collecting soil samples at 25 day intervals. The results showed that changes of soil organic matter (OM), total nitrogen (N) and available phosphorus (P) were similar from winter (December) to early spring (March). Over this time, content of soil OM and N decreased slowly and level of soil available P had little change, in contrast, in spring when it was warm, net loss of soil OM, N and P were much greater. This was coincide with the output of bamboo shoot production. By d100 in April, treatment of BL and CK resulted in the least net loss of soil OM, N and P in comparison with those at d0. And RS and RH did the most. Soil enzymatic activities of hydrogen peroxidase, sucrase, phosphatase, urase and protease were generally higher in mulch treated plots than CK. And soil enzyme activities in BL treated plots were highest. [ABSTRACT FROM AUTHOR]

Rice black-streaked dwarf virus (RBSDV), classified under the Reoviridae, Fijivirus genus, caused an epidemic in the eastern provinces of China and other East Asian countries and resulted in severe yield loss in rice and wheat production. RBSDV is transmitted by the small brown planthopper (SBPH, Laodelphax striatellus Fallén) in a persistent manner. In order to provide a stable and cost-effective detection probe, in this study we selected three DNA aptamers (R3, R5 and R11) by an optimized, standardized and time saving emulsion PCR-based SELEX, for the detection of RBSDV outer-shell P10 protein for in situ localization studies in the midgut of SBPH. The specificity of these three DNA aptamers was tested through detection of the P10 protein using an enzyme-linked oligonucleotide assay (ELONA) and aptamer-based dot-blot ELISA. All three DNA aptamers can be used to detect RBSDV P10 protein by immunofluorescent labeling in the midgut of RBSDV-infected SBPH. These data show that the selected aptamers can be used for the detection of RBSDV P10 protein in vitro and in vivo. This is the first report of aptamers being selected for detection of a rice virus capsid protein. [ABSTRACT FROM AUTHOR]

The reverse transcription quantitative polymerase chain reaction (RT-qPCR) has been widely used to determine gene functions in Laodelphax striatellus (Fallén) (small brown planthopper). Selection of suitable reference gene(s) for normalizations of RT-qPCR data is critical for reliable results. To date, reports on identification of suitable L. striatellus reference genes are still very limited. L. striatellus is a destructive rice pest and it can transmit multiple viruses, including Rice black-streaked dwarf virus (RBSDV), Rice stripe virus (RSV), and Maize rough dwarf virus (MRDV), to many important cereal crops worldwide. In this study, we examined the stablity of seven selected candidate reference genes in L. striatellus at different developmental stages, in different tissues, in RBSDV- or RSV-infected L. striatellus or in RBSDV-infected and Lssynaptojanin 1 (LsSYNJ1)-silenced L. striatellus. The RT-qPCR data representing individual candidate genes were analyzed using five different methods: the delta Ct method, geNorm, NormFinder, BestKeeper, and the RefFinder algorithm, respectively. The most stable reference gene for the specific condition was selected according to a comprehensive analysis using the RefFinder method. Ribosomal protein L5 (LsRPL5) and LsRPL8 are the most stably expressed genes in L. striatellus at different developmental stages. Alpha-1-tubulin (Lsα-TUB) is the most stably expressed reference gene in different tissues of RBSDV viruliferous (RBSDV-V) or non-viruliferous (RBSDV-NV) L. striatellus. LsRPL8 is the most stably expressed reference gene in RBSDV-V or RSV viruliferous (RSV-V) L. striatellus, while beta-tubulin (Lsβ-TUB) is the most stably expressed reference gene in RBSDV-V and LsSYNJ1-silenced L. striatellus. The selected reference genes were further investigated during analyses of RBSDV P5-1 and P10 gene expression in different tissues from RBSDV-V or RBSDV-NV L. striatellus. The stably expressed reference genes identified in this study will benefit future gene function studies using L. striatellus. [ABSTRACT FROM AUTHOR]

Background: Porphyromonas gingivalis (P. gingivalis), one of the main pathogenic bacteria involved in periodontitis, induces the expression of intercellular adhesion molecule − 1 (ICAM-1) and monocyte-endothelial cell adhesion. This effect plays a pivotal role in atherosclerosis development. Macrophage migration inhibitory factor (MIF) is a multifunctional cytokine and critically affects atherosclerosis pathogenesis. In this study, we tested the involvement of MIF in the P. gingivalis ATCC 33277-enhanced adhesive properties of endothelial cells. Results: Endothelial MIF expression was enhanced by P. gingivalis ATCC 33277 infection. The MIF inhibitor ISO-1 inhibited ICAM-1 production in endothelial cells, and monocyte-endothelial cell adhesion was induced by P. gingivalis ATCC 33277 infection. However, the addition of exogenous human recombinant MIF to P. gingivalis ATCC 33277-infected endothelial cells facilitated monocyte recruitment by promoting ICAM-1 expression in endothelial cells. Conclusions: These experiments revealed that MIF in endothelial cells participates in the pro-atherosclerotic lesion formation caused by P. gingivalis ATCC 33277 infection. Our novel findings identify a more detailed pathological role of P. gingivalis ATCC 33277 in atherosclerosis. [ABSTRACT FROM AUTHOR]

A correction to the article "A Genetic Screen Identifies a Requirement for Cysteine-Rich-Receptor-Like Kinases in Rice NH1 (OsNPR1)-Mediated Immunity" that was published in the July 6, 2016 issue is presented.

Bamboo plants have been proven to be rich in phytolith-occluded carbon (PhytOC) and play an important role in reducing atmospheric concentrations of CO2. The object of this paper was to obtain more accurate methods for estimation of PhytOC stock in monopodial bamboo because previous studies may have underestimated it. Eight monopodial bamboo species, widely distributed across China, were selected and sampled for this study in their own typical distribution areas. There were differences (P < 0.05) both in phytolith content (Phytolith/dry biomass) across leaves, branches and culm, and in PhytOC content (PhytOC/dry biomass) across leaves and branches between species, with a trend of leaf > branch > culm. The average PhytOC stored in aboveground biomass and PhytOC production flux contributed by aboveground biomass varied substantially, and they were 3.28 and 1.57 times corresponding dates in leaves, with the highest in Phyllostachys glauca McClure and lowest in Indocalamus tessellatus (Munro) Keng f. It can be concluded that it could be more accurate to estimate PhytOC stock or PhytOC production flux by basing on whole aboveground biomass rather than on leaf or leaf litter only. The whole biomass should be collected for more estimation of bamboo PhytOC sequestration capacity in the future. [ABSTRACT FROM AUTHOR]

Coxsackievirus B3 (CVB3) is a causative agent of viral myocarditis, pancreatitis, and meningitis in humans. Although the susceptibility of CVB3-induced acute pancreatitis is age-dependent, the underlying mechanisms remain unclear. Here we identified the host factor Golgi matrix protein 130 (GM130) as a novel target of CVB3 during CVB3-induced acute pancreatitis. The viral protein VP1 interacted with GM130, disrupted GM130-GRASP65 complexes, and caused GM130 degradation, which may lead to disruption of the Golgi ribbon and development of acute pancreatitis in mice. Interestingly, the expression level of GM130 in mouse pancreas was age-dependent, which was nicely correlated with the age-associated susceptibility of CVB3-induced acute pancreatitis. Furthermore, interference RNA-mediated knockdown of GM130 significantly reduced CVB3 replication in HeLa cells. Taken together, the study identified GM130 as a novel target of CVB3, which may implicate in the pathogenesis of CVB3-induced acute pancreatitis. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) could be produced during the plant-virus compatible interaction. However, the cell responses regulated by the enhanced H2O2 in virus infected plant are largely unknown. To make clear the influence of Rice black-streaked dwarf virus (RBSDV) infection on H2O2 accumulation, we measured the content of H2O2 and found the H2O2 level was increased in rice seedlings inoculated with RBSDV. To reveal the responses initiated by the enhanced H2O2 during plant-virus interaction, the present study investigated the global proteome changes of rice under long-term RBSDV infection. Approximately 1800 protein spots were detected on two-dimensional electrophoresis (2-DE) gels. Among them, 72 spots were found differently expressed, of which 69 spots were successfully identified by MALDI-TOF/TOF-MS. Furthermore, the differentially expressed proteins induced by RBSDV infection were compared to that induced by H2O2. 19 proteins corresponding to 37 spots, which were differentially expressed under RBSDV infection, were observed differentially expressed under H2O2 stress as well. These overlapping responsive proteins are mainly related to photosynthesis, redox homeostasis, metabolism, energy pathway, and cell wall modification. The increased H2O2 in RBSDV infected plant may produce an oxidative stress, impair photosynthesis, disturb the metabolism, and eventually result in abnormal growth. The data provide a new understanding of the pivotal role of H2O2 in rice-RBSDV compatible interaction. [ABSTRACT FROM AUTHOR]