Nuclear receptor hormone receptor 39 is required for locust moulting by regulating the chitinase and carboxypeptidase genes.

The nuclear receptor-mediated 20-hydroxyecdysone (20E) signalling pathway plays crucial roles in insects by initiating and regulating moulting and metamorphosis. In the present study, we identified and characterized a cDNA encoding a putative nuclear receptor protein (Locusta migratoria hormone receptor 39, LmHR39) based on L. migratoria transcriptomics data. Reverse-transcription quantitative PCR (RT-qPCR) revealed that LmHR39 shows low-level expression in the early days of fifth-instar nymphs, and peak expression occurs on day 5, which is followed by a decrease before ecdysis. LmHR39 transcription could be induced by 20E in vivo and was significantly suppressed by knocking down the expression of the L. migratoria ecdysone receptor gene and early-late gene LmHR3. After RNA interference of LmHR39 with double-stranded RNA (dsRNA), 85% of the insects showed abnormal morphology, with curly wings after moulting and delayed eclosion time. Haematoxylin and eosin staining indicated that apolysis of the integument and wing pad cuticle in the dsLmHR39-treated insects was delayed compared to that in the dsRNA for green fluorescent protein-injected control. Furthermore, RNA-sequencing and RT-qPCR analysis showed the expression level of carboxypeptidase genes (Carboxypeptidase A (CPA) and Carboxypeptidase M (CPM)) and chitin degrading genes (LmChitinase5 (LmCHT5) and LmChitinase10 (LmCHT10)) dramatically declined in the dsLmHR39-treated insects, implying that the LmHR39-mediated 20E signalling pathway is involved in the regulation of carboxypeptidase genes (CPA and CPM) and chitinase genes (LmCHT5 and LmCHT10), and participated in apolysis of the integument and wing pads during locust moulting.

LmCDA1 organizes the cuticle by chitin deacetylation in Locusta migratoria.

Cells produce an extracellular matrix (ECM) with a stereotypic organization that is important for tissue function. The insect cuticle is a layered ECM that mainly consists of the polysaccharide chitin and associated proteins adopting a quasi-crystalline structure. Our understanding of the molecular mechanisms deployed during construction of the highly ordered protein-chitin ECM so far is limited. In this study, we report on the role of the chitin deacetylase 1 (LmCDA1) in the organization of the protein-chitin ECM in the migratory locust Locusta migratoria, and LmCDA1 localizes predominantly to the apical tier of the protein-chitin ECM, but it is also found in lower regions. Reduction of LmCDA1 function correlates with lower amounts of chitin and impedes conversion of chitin to chitosan by deacetylation. Establishment of the quasi-crystalline architecture of the protein-chitin ECM is, however, independent of LmCDA1 activity, but it is dependent on another chitin deacetylase, LmCDA2, which has no detectable effects on chitin deacetylation and, as shown previously, no influence on chitin content. Our data reveal that LmCDA1 and LmCDA2 act in parallel and independently from each other in defining the dimensions of the cuticle. Both enzymes are non-uniformly distributed within the protein-chitin matrix, suggesting a site-autonomous function.

Genetic Loci Governing Grain Yield and Root Development under Variable Rice Cultivation Conditions.

Drought is the major abiotic stress to rice grain yield under unpredictable changing climatic scenarios. The widely grown, high yielding but drought susceptible rice varieties need to be improved by unraveling the genomic regions controlling traits enhancing drought tolerance. The present study was conducted with the aim to identify quantitative trait loci (QTLs) for grain yield and root development traits under irrigated non-stress and reproductive-stage drought stress in both lowland and upland situations. A mapping population consisting of 480 lines derived from a cross between Dular (drought-tolerant) and IR64-21 (drought susceptible) was used. QTL analysis revealed three major consistent-effect QTLs for grain yield (qDTY1.1, qDTY1.3 , and qDTY8.1 ) under non-stress and reproductive-stage drought stress conditions, and 2 QTLs for root traits (qRT9.1 for root-growth angle and qRT5.1 for multiple root traits, i.e., seedling-stage root length, root dry weight and crown root number). The genetic locus qDTY1.1 was identified as hotspot for grain yield and yield-related agronomic and root traits. The study identified significant positive correlations among numbers of crown roots and mesocotyl length at the seedling stage and root length and root dry weight at depth at later stages with grain yield and yield-related traits. Under reproductive stage drought stress, the grain yield advantage of the lines with QTLs ranged from 24.1 to 108.9% under upland and 3.0-22.7% under lowland conditions over the lines without QTLs. The lines with QTL combinations qDTY1.3 +qDTY8.1 showed the highest mean grain yield advantage followed by lines having qDTY1.1 +qDTY8.1 and qDTY1.1 +qDTY8.1 +qDTY1.3 , across upland/lowland reproductive-stage drought stress. The identified QTLs for root traits, mesocotyl length, grain yield and yield-related traits can be immediately deployed in marker-assisted breeding to develop drought tolerant high yielding rice varieties.

Molecular Characterization of Six Small Heat Shock Proteins and Their Responses Under Cadmium Stress in Oxya chinensis (Orthoptera: Acridoidea).

Small heat shock proteins (sHSPs) have been implicated in many physiological processes and play important roles in the response to various stresses. In this study, the full-length sequences of six sHSPs: OcHSP19.1, 19.8, 20.4, 20.7, 21.1, and 23.8 were obtained from the rice grasshopper Oxya chinensis transcriptome database. The deduced amino acid sequences of the six OcsHSPs contain a typical α-crystallin domain, which consists of approximately 100 amino acid residues and five ß-strands. The phylogenetic analysis suggested that OcHSP23.8 was orthologous to the sHSPs of other species and that OcHSP19.1, 20.4, 20.7, and 21.1 were species specific, whereas OcHSP19.8 did not cluster closely to Orthoptera but was placed on the basal end of the cluster. Developmental stage-dependent and tissue-specific expression patterns were evaluated using quantitative real-time polymerase chain reaction. The six genes were expressed in all developmental stages and showed clear tissue specificity. The cadmium acute experiment indicates that Cd(2+) can induce the six genes. However, various response patterns were observed among these genes under Cd(2+) stress conditions. OcHSP19.1, 19.8, 20.4, and 20.7 were highly induced by 2.61 mM Cd(2+) at 24 h. OcHSP23.8 was significantly upregulated by 2.61 mM Cd(2+) at 6 h. For OcHSP21.1, the highest expression levels were found after treatment with 0.87 mM Cd(2+) for 24 h, 1.74 mM Cd(2+) for 36 h, and 2.61 mM Cd(2+) for 12 h. These differential characteristics will facilitate future investigations into the physiological functions of sHSPs.

Effect of dietary cadmium on the activity of glutathione S-transferase and carboxylesterase in different developmental stages of the Oxya chinensis (Orthoptera: Acridoidea).

Glutathione S-transferases (GSTs) and carboxylesterases (CarEs) play important roles in the detoxification of endogenous and exogenous compounds. In this study, the biochemical effects of dietary cadmium (Cd) on the activities of GST and CarE in different developmental stages of the rice grasshopper Oxya chinensis Thunberg were studied. The results showed that the effects of the Cd concentration and developmental stage on GST activity were statistically significant. GST activity in O. chinensis increased at the highest Cd concentration in most nymphs, suggesting that GST is typically inducible by Cd. However, GST activity was inhibited in adults under Cd stress owing to life-stage-specific physiological characteristics. The results showed that the substrates, developmental stage, and Cd concentration had statistically significant effects on CarE activity. In most studies of CarE activity, the interaction between any two studied factors was statistically significant, although the interaction effects of the substrates, developmental stages, and Cd concentrations were not significant, which implied that the insect physiological condition and the external environmental may affect CarE activity. The results suggest that the insect's life stage and enzyme substrates should be considered when enzyme activity under Cd stress is studied.

Analyses of microbial consortia in the starter of Fen Liquor.

AIMS: This study aimed to determine the microbial diversity in the starter of Fen Liquor. METHODS AND RESULTS: The plate method was used to enumerate the micro-organisms; meanwhile, the 16S rDNA of bacteria and the internal transcribed spacer of fungi were used to determine microbial diversity. Several genera were accordingly identified. Among the bacteria, Lactobacillales and Actinomycetales were detected only on the surface of the starter, whereas Bacillales was dominant within the starter. Among the fungi, Saccharomycopsis and Issatchenkia were the main genera in surface and interior starter, respectively; in addition, Thermomyces was found in interior starter, while other species of fungi were detected on the surface. CONCLUSIONS: The culture-dependent and polymerase chain reaction-based methods revealed the significant microbial diversity in different locations in the starter of Fen Liquor. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to identify the bacterial and fungal communities associated with the starter of Fen Liquor using both traditional and molecular methods; it is also the first to compare the microbial diversity on the surface of starter with that in the interior. The results enrich our knowledge on liquor-related micro-organisms, and can be used to promote the development of the traditional fermentation technology.

Mechanisms of organophosphate resistance in a field population of oriental migratory locust, Locusta migratoria manilensis (Meyen).

The susceptibilities to three organophosphate (OP) insecticides (malathion, chlorpyrifos, and phoxim), responses to three metabolic synergists [triphenyl phosphate (TPP), piperonyl butoxide (PBO), and diethyl maleate (DEM)], activities of major detoxification enzymes [general esterases (ESTs), glutathione S-transferases (GSTs), and cytochrome P450 monooxygenases (P450s)], and sensitivity of the target enzyme acetylcholinesterase (AChE) were compared between a laboratory-susceptible strain (LS) and a field-resistant population (FR) of the oriental migratory locust, Locusta migratoria manilensis (Meyen). The FR was significantly resistant to malathion (57.5-fold), but marginally resistant to chlorpyrifos (5.4) and phoxim (2.9). The malathion resistance of the FR was significantly diminished by TPP (synergism ratio: 16.2) and DEM (3.3), but was unchanged by PBO. In contrast, none of these synergists significantly affected the toxicity of malathion in the LS. Biochemical studies indicated that EST and GST activities in the FR were 2.1- to 3.2-fold and 1.2- to 2.0-fold, respectively, higher than those in the LS, but there was no significant difference in P450 activity between the LS and FR. Furthermore, AChE from the FR showed 4.0-fold higher activity but was 3.2-, 2.2-, and 1.1-fold less sensitive to inhibition by malaoxon, chlorpyrifos-oxon, and phoxim, respectively, than that from the LS. All these results clearly indicated that the observed malathion resistance in the FR was conferred by multiple mechanisms, including increased detoxification by ESTs and GSTs, and increased activity and reduced sensitivity of AChE to OP inhibition.

Application of YLD calculation in assessing disease data--an analysis of 4 diseases in 2 regions.

The objective of the current study is to discuss the problems related to how data is used to calculate Years Lost with Disability (YLD) with the method recommended by the World Bank. The study includes collecting useful data, estimating disease duration and average age of disease onset, adjusting incidence and prevalence data by means of a software programme, DISMOD (Harvard University Incidence & Prevalence Model), and assessing the importance of YLD calculation for different diseases. Remission and fatality rates of 3 diseases were estimated by experts at 2 round consultations. Incidence rates, disease duration and average age of disease onset were calculated and adjusted by DISMOD. YLD due to schizophrenia is the highest among 4 diseases in two regions. YLD is 18.88% in disability adjusted life year for 4 diseases in Xiacheng District, and 19.97% in Fuyang County. Available data can be used for the calculation of YLD after being adjusted. DISMOD is a useful instrument to test the internal consistency of incidence, prevalence, remission and fatality rate. The adjusted data are acceptable to experts and DISMOD. To get rational remission and fatality rates, we can use a cohort method through expert consultations. To reflect overall burden of disease, YLD calculation should be used.

Child mortality patterns in rural areas of Anhui and Henan provinces in China, 1990.

County-based IMR and U5MR in Anhui and Henan provinces in China were estimated and analyzed by using the 1990 Census Data. Census was conducted on July 1, 1990, the number of deaths only occurred in the first half year of 1990 was collected. In order to obtain the total population and total number of deaths in the same year, the total number of deaths in each age-sex group for the whole 1990 was then estimated by taking the death number in the first half of 1990 as the base and multiplying a coefficient, which varied in different age-sex-region groups. Two major adjustments for some possible under-reporting cases in female birth and infant death were made. If the sex ratio at age 0 in some counties was beyond 1.2, then it was taken as 1.15 for rural counties and 1.10 for urban cities, which were the estimates of sex ratios for the children at age 5 in the national 1% Population Sampling Survey in 1995. The adjustment for IMR were made by comparing the segment of the county lift table from age 15 through 59 with that from the same age groups in the international and Chinese Model Life Tables. The IMR in the county life table would be substituted by the one in the closest Model Life Talbe, if it was less than in the latter. The findings of the analysis may be summarized as follows: (i) Total county-based IMR and U5MR were 33.4 per 1,000 and 41.4 per 1,000 respectively, with great variations between urban cities (25.4 per 1,000 for IMR and 31.4 per 1,000 for U5MR) and rural counties (35.1 per 1,000 for IMR and 43.6 per 1,000 for U5MR). There were also significant differences in child mortality between nationally identified poor counties and other counties in rural areas. In the poor counties the total IMR was 40.7 per 1,000 living births in average while in non-poor counties it was only 33.2 per 1,000 in average (P < 0.05). The U5MR in poor counties was 25 percent higher than in non-poor counties (51.5 vs 40.9 per 1,000 living births). (ii) Statistically significant correlation between child mortality and socio-economic variables was revealed from the data set, among which gross social economic products per capita was found to have the strongest relationship with child mortality. The negative correlation was found between child mortality and a set of so-called 'rich' variables including the gross social products, gross agricultural products, gross industrial products and the proportions of high-educated population at county level, whereas the positive correlation was found between child mortality and a set of 'poor' variables, such as proportions of residents with lower level of education and illiteracy rate. (iii) Differences in child mortality between these two provinces were found, which were identical to the trends of differences in socio-economic indicators between them. Lower child mortality proved to be associated with better socio-economic conditions (higher per capita products, higher proportions of residents with higher level of education, lower proportion of less educated people and illiteracy) in province Henan. (iv) A simple linear regression model was developed separately for Henan and Anhui to predict the IMR and U5MRs in each stage of economic development, where the dependent variables were the logarithm of IMR and U5MR, and the independent variables were the quintiles of the output value of gross products (GOP). It was found that at the first quintile, which was equivalent to 800 yuan of GOP in average, the predicted IMR and U5MR would reach 40 per 1,000 and 51 per 1,000 respectively. It would decline to 38 per 1,000 for IMR and 47 per 1,000 for U5MR in the second lowest quintile. Dramatic drop of child mortality was found between the second quintile and the third quintile, where 6 per 1,000 decline would occur for both IMR and U5MR. The decline would continue subsequently, but slower. The prediction of child mortality in rural counties could be used as a reference to assess counties at different stages of socio-