A critical step during rice (Oryza sativa) cultivation is dense planting: a wider tiller angle will increase leaf shade and decrease photosynthesis efficiency, whereas a narrower tiller angle makes for more efficient plant architecture. The molecular basis of tiller angle remains unknown. This research demonstrates that tiller angle is controlled by a major quantitative trait locus, TAC1 (Tiller Angle Control 1). TAC1 was mapped to a 35-kb region on chromosome 9 using a large F 2 population from crosses between an indica rice, IR24, which displays a relatively spread-out plant architecture, and an introgressed line, IL55, derived from japonica rice Asominori, which displays a compact plant architecture with extremely erect tillers. Genetic complementation further identified the TAC1 gene, which harbors three introns in its coding region and a fourth 1.5-kb intron in the 3¢-untranslated region. A mutation in the 3¢-splicing site of this 1.5-kb intron from 'AGGA' to 'GGGA' decreases the level of tac1, resulting in a compact plant architecture with a tiller angle close to zero. Further sequence verification of the mutation in the 3¢-splicing site of the 1.5-kb intron revealed that the tac1 mutation 'GGGA' was present in 88 compact japonica rice accessions and TAC1 with 'AGGA' was present in 21 wild rice accessions and 43 indica rice accessions, all with the spread-out form, indicating that tac1 had been extensively utilized in densely planted rice grown in high-latitude temperate areas and at high altitudes where japonica rice varieties are widely cultivated.

Dietary iron oxide nanoparticles are shown to ameliorate neurodegeneration in a Drosophelia Alzheimer's disease model. Iron oxide nanoparticles can mimic catalase and can decompose reactive oxygen species (ROS). This has potential therapeutic uses for aging, metabolic disorders, and neurodegenerative diseases, in which increased production of ROS is closely implicated.

Grain size is an important yield-related trait in rice. Intensive artificial selection for grain size during domestication is evidenced by the larger grains of most of today's cultivars compared with their wild relatives. However, the molecular genetic control of rice grain size is still not well characterized. Here, we report the identification and cloning of Grain Size 6 (GS6), which plays an important role in reducing grain size in rice. A premature stop at the +348 position in the coding sequence (CDS) of GS6 increased grain width and weight significantly. Alignment of the CDS regions of GS6 in 90 rice materials revealed three GS6 alleles. Most japonica varieties (95%) harbor the Type I haplotype, and 62.9% of indica varieties harbor the Type II haplotype. Association analysis revealed that the Type I haplotype tends to increase the width and weight of grains more than either of the Type II or Type III haplotypes. Further investigation of genetic diversity and the evolutionary mechanisms of GS6 showed that the GS6 gene was strongly selected in japonica cultivars. In addition, a "ggc" repeat region identified in the region that encodes the GRAS domain of GS6 played an important historic role in the domestication of grain size in rice. Knowledge of the function of GS6 might aid efforts to elucidate the molecular mechanisms that control grain development and evolution in rice plants, and could facilitate the genetic improvement of rice yield.

BackgroundThe citrus red mite is a worldwide citrus pest and a common sensitizing allergen of asthma and rhinitis. It has developed strong resistance to many registered acaricides, However, the molecular mechanisms of resistance remain unknown. we therefore used next generation sequencing technology to investigate the global transcriptomes between resistant strains and susceptible strains.ResultsWe obtained 34,159, 30,466 and 32,217 unigenes by assembling the SS reads, RS reads and SS&RS reads respectively. There are total 17,581 annotated unigenes from SS&RS reads by BLAST searching databases of nr, the Clusters of Orthologous Groups (COGs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) with an E-value ≤ 1e-5, in which 7,075 unigenes were annotated in the COG database, 12, 712 unigenes were found in the KEGG database and 3,812 unigenes were assigned to Gene ontology (GO). Moreover, 2,701 unigenes were judged to be the differentially expressed genes (DEGs) based on the uniquely mapped reads. There are 219 pathways in all annotated unigenes and 198 pathways in DEGs that mapped to the KEGG database. We identified 211 metabolism genes and target genes related to general insecticide resistance such as P450 and Cytochrome b, and further compared their differences between RS and SS. Meanwhile, we identified 105 and 194 genes related to growth and reproduction, respectively, based on the mode of action of Hexythiazox. After further analyses, we found variation in sequences but not in gene expression related to mite growth and reproduction between different strains.ConclusionTo our knowledge, this is the first comparative transcriptome study to discover candidate genes involved in phytophagous mite resistance. This study identified differential unigenes related to general pesticide resistance and organism growth and reproduction in P. citri. The assembled, annotated transcriptomes provide a valuable genomic resource for further understanding the molecular basis of resistance mechanisms.

The developmental regulation of grasses lemma and palea and their relationship to the floral organs in dicots had been variously explicated and extensively debated. Here, we characterized a triangular hull mutant th1-1 from EMS-mutagenized Oryza sativa ssp. indica cv. 93-11. The th1-1 mutant exhibited obviously triangular hull with tortuous and slender lemma/palea. Using a map-based cloning strategy, the TH1 gene was narrowed down to a 60-kb region on the long arm of chromosome 2. Sequence verification revealed that the th1-1 mutant harbored 1-bp deletion in exon 2 of LOC_Os02g56610 which resulted in a frame-shift mutation. The RNA-interference transgenic plants of LOC_Os02g56610 displayed a similar phenotype to the th1 mutant. Consequently, LOC_Os02g56610 was identified as the TH1 gene which encoded 248 amino acids and contained a DUF640 domain. RT-PCR analysis and GUS staining showed that the transcripts of TH1 mainly accumulated in young inflorescence, lemma and palea of spikelet. These results suggested that TH1 was an important gene controlling the lemma and palea development in rice.

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The endomembrane system, which sorts proteins and membranes through the secretory and endocytic pathways, is critical for cellular functions in eukary-otes (Otegui and Spitzer, 2008; Richter et al., 2009; Contento and Bassham, 2012). The plant endomembrane system comprises the endoplasmic reticulum (ER), Golgi complex, trans-Golgi network (TGN), prevacuolar compartment (PVC)/multivesicular bodies (MVB), and vacuoles (Contento and Bassham, 2012). The endomembrane system, by enabling protein modification and sorting, plays important roles in cell polarity, cytokinesis, cell wall formation, signaling, and stress tolerance (

Background: The present clinical trial investigated the potential influences of dosage and age on the pharmacokinetic properties and safety profile of HSK3486, and whether any adjustment in dosing regimen is necessary in elderly patients.Methods: Twenty-four elderly participants (65–73 years) were apportioned to three equal cohorts to receive a single IV bolus of 0.2, 0.3, and 0.4 mg/kg HSK3486, respectively. An additional control group comprised eight non-elderly participants (21–44 years), who each received a single IV bolus dose of 0.4 mg/kg. Safety was assessed throughout the study, and the clinical effects were assessed based on modified observer’s assessment of alertness/sedation and bispectral index (BIS) monitor. Pharmacokinetic parameters were calculated.Results: The rates of drug-related adverse reactions among the elderly groups were a little higher than that of the non-elderly, and were slightly higher in the elderly receiving 0.4 mg/kg compared with the elderly given lower doses. The pharmacokinetic characteristics of 0.4 mg/kg HSK3486 in the elderly and non-elderly were comparable. The time to recovery was similar in elderly 0.3 mg/kg, elderly 0.4 mg/kg and non-elderly 0.4 mg/kg groups. In the elderly 0.2 mg/kg group, the time to loss of consciousness was a little longer, and the time to recovery was shorter, relative to the other three groups.Conclusions: Administration of 0.3 mg/kg to the elderly and 0.4 mg/kg to the non-elderly were similarly efficacious. A dose of HSK3486 of 0.3 mg/kg may be chosen for clinical use in elderly patients.