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Being sessile organisms, plants suffer from various abiotic stresses including low temperature. In particular, male reproductive development of plants is extremely sensitive to cold which may dramatically reduce viable pollen shed and plant fertility. Cold stress disrupts stamen development and prominently interferes with the tapetum, with the stress-responsive hormones ABA and gibberellic acid being greatly involved. In particular, low temperature stress delays and/or inhibits programmed cell death of the tapetal cells which consequently damages pollen development and causes male sterility. On the other hand, studies in Arabidopsis and crops have revealed that ectopically decreased temperature has an impact on recombination and cytokinesis during meiotic cell division, implying a putative role for temperature in manipulating plant genomic diversity and architecture during the evolution of plants. Here, we review the current understanding of the physiological impact of cold stress on the main male reproductive development processes including tapetum development, male meiosis and gametogenesis. Moreover, we provide insights into the genetic factors and signaling pathways that are involved, with putative mechanisms being discussed.

Glycerol monomyristate (GMM) is a promising antimicrobial substance due to its broad antibacterial spectrum: however, the critical lethal action in its antimicrobial mechanism for foodborne pathogens remains unclear. In the present study, the inhibitory activities of GMM on Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Candida albicans (C. albicans) were compared, and its membrane and intracellular action mechanism was investigated. The results showed that the susceptibility of E. coli to GMM was the highest, followed by S. aureus, and C. albicans being the poorest. Using flow cytometry, the GMM dose causing above 50% permeability ratio on E. coli was lower than that on S. aureus. The images from scanning electron microscope revealed no doses difference existed between the two strains when the obvious cell damage occurred. Furthermore, cell cycle and multiple fluorescent staining assays showed only the cell division of E. coli and S. aureus, excluding that of C. albicans, was obviously affected at 1/4 MIC and 1/2 MIC, indicating that the DNA interfere and subsequent cell division inhibition was likely to be the critical lethal action with doses near MIC, which can also explain the poor sensitivity of C. albicans.ImportanceFoodborne pathogens, as a common source of biological pollution in the food industry, can cause millions of food poisoning incidents each year, which poses great risks to consumers’ health and safety. The use of monoglyceride as an edible surfactant to inhibit the growth of food-borne microorganisms has been a long time, but the relevant antibacterial mechanism is too broad to accurately grasp its key lethal effect and its action doses, which not only affects the antibacterial efficiency, but also may result in the abnormalities of food flavor when adding at overdoses. The significance of the study is to identify the key lethal effect and its action doses, which will greatly enhance the understanding of the response mechanism of different types of foodborne pathogens to monoglycerides, and provide a more reasonable reference for differential control and treatment of different gastrointestinal infections when combined with antibiotics in clinical.

Background GLORIA is an ongoing large pragmatic trial that examines harm, benefit and costs of low-dose glucocorticoids added to the standard treatment of RA patients of 65 years or older. The eligibility criteria are non-restrictive: RA, age ≥65 years, disease activity score (DAS28) of ≥2.6, and no current glucocorticoid treatment. Patients with comorbidity are expressly included, and the impact of trial procedures on normal care is minimal. Nevertheless, inclusion proves to be challenging. We have prospectively sampled all the reasons for ineligibility across a number of centres in different countries participating in the GLORIA trial. Methods Rheumatologists from 8 centres in Germany, Hungary, The Netherlands, Portugal and Romania screened the patient list of at least two full clinic days. For each patient, the eligibility and all possible reasons of exclusion were recorded. Results In total, 385 patients were screened. Of these patients, 15 (4%) were eligible to participate in the GLORIA trial. In Germany, Romania and Portugal (Lisbon) none of the screened patients proved eligible. The most common reasons for ineligibility were inactive disease and age (both 58%) (table 1). Current glucocorticoid use was reported in 28%, 5% had a temporary reason (i.e. recent switch of therapy or glucocorticoid use), and 51% had more than one reason for ineligibility. We found remarkable differences between the sites in the distribution of the main reasons for ineligibility (table 1). Of the eligible patients, 1 was already participating, 3 were included after this screening, and 2 were currently considering participation; 9 declined participation (most common reasons: fear of glucocorticoids, not interested to participate, preference for GC injections or declining additional therapy). Conclusions In this prospective study, we found remarkable differences between countries in reasons for non-participation in our ongoing GLORIA trial. The willingness of eligible patients to participate was low in this elderly population, despite the pragmatic design. Earlier studies also showed that it is challenging to include elderly patients in a clinical trial.1 2 Pre-screening of patients in potential sites can provide important information on the potential to recruit patients in a trial, but the actual willingness of patients to participate remains hard to predict. References [1] Calamia M, et al. I’d Do Anything for Research, But I Won’t Do That: Interest in Pharmacological Interventions in Older Adults Enrolled in a Longitudinal Aging Study. PLoS One2016;11:e0159664. [2] Denson AC, et al. Participation of the elderly population in clinical trials: barriers and solutions. Cancer Control2014;21:209–14. Acknowledgements This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 6 34 886. Disclosure of Interest None declared

The number of rice grains on a panicle is an important index for variety screening during high-quality rice [Oryza Sativa L.] breeding. For an in-vivo image-based measurement, the occlusion and overlapping among grains are the major challenges in non-destructive precise phenotyping of the on-panicle grains. In order to tackle these challenges, this paper describes a correction-model-referred on-panicle grain counting method based on the area of the rice panicle and its edge contour wavelet analysis. First, we assume that a deterministic correlation exists between the number of grains of the panicle and the traits of its edge contour morphology, which reflects the extent to which the grains are occluded. Second, a method for coarsely estimating grain number per panicle is proposed based on the projective area of the panicle in the image and the average area of a rice grain. Finally, a correction model which is built with the average wavelet frequency of the edge contour of the panicle is employed to correct the estimated value of the grain number. Two randomly selected cases are investigated in detail, showing that computation accuracy with a correction model is increased by 26% and 23% respectively when compared to that of the naive area-based computation. In conclusion, we reveal and validate the relationship between the number of grains of the panicle and the fluctuation frequency of its edge contours. Further, experiments show that errors caused by overlapping and occlusion scenarios can be alleviated with the estimation and correction hybrid models, achieving an average accuracy of 94% compared to the results of manual counting.

Drug resistance to Osimertinib, a 3rd-generation EGFR-TKI is inevitable. Autophagy plays a contradictory role in resistance of 1stand 2ndgeneration EGFR-TKI, and its significance in osimertinib resistance is much less clear. We therefore investigated whether autophagy determines osimertinib resistance. First, osimertinib induced autophagy to a much greater extent than that of gefitinib, and autophagy inhibition further increased osimertinib efficacy. Next, enhanced autophagy was found in osimertinib resistant cells and autophagy inhibition partially reversed osimertinib resistance. Enhanced stem-cell like properties were found in resistant cells, and siRNA-knock down ofSOX2orALDH1A1reversed osimertinib resistance. Of note, autophagy inhibition or siRNA-knock down of Beclin-1 decreased expression of SOX2 and ALDH1A1 and stem-cell like properties. Next, autophagy inhibition and osimertinib in combination effectively blocked tumor growth in xenografts, which was associated with decreased autophagy and stem cell-like propertiesin vivo. Finally, enhanced autophagy was found in lung cancer patients with resistance to osimertinib. In conclusion, the current study delineates a previously unknown function of autophagy in determining osimertinib resistance through promoting stem-cell like properties.

Root traits such as root angle and hair length influence resource acquisition particularly for immobile nutrients like phosphorus (P). Here, we attempted to modify root angle in rice by disrupting the OsAUX1 auxin influx transporter gene in an effort to improve rice P acquisition efficiency. We show by X-ray microCT imaging that root angle is altered in the osaux1 mutant, causing preferential foraging in the top soil where P normally accumulates, yet surprisingly, P acquisition efficiency does not improve. Through closer investigation, we reveal that OsAUX1 also promotes root hair elongation in response to P limitation. Reporter studies reveal that auxin response increases in the root hair zone in low P environments. We demonstrate that OsAUX1 functions to mobilize auxin from the root apex to the differentiation zone where this signal promotes hair elongation when roots encounter low external P. We conclude that auxin and OsAUX1 play key roles in promoting root foraging for P in rice., Plant root architecture can adapt to different nutrient conditions in the soil. Here Giri et al. show that the rice auxin influx carrier AUX1 mobilizes auxin from the root apex to the differentiation zone and promotes root hair elongation when roots encounter low external phosphate.

The accurate monitoring and quantification of genetically modified organisms (GMOs) are key points for the implementation of labeling regulations, and a certified reference material (CRM) acts as the scaleplate for quantifying the GM contents of foods/feeds and evaluating a GMO analytical method or equipment. Herein we developed a series of CRMs for transgenic rice event G6H1, which possesses insect-resistant and herbicide-tolerant traits. Three G6H1 CRMs were produced by mixing seed powders obtained from homozygous G6H1 and its recipient cultivar Xiushui 110 at mass ratios of 49.825%, 9.967%, and 4.986%. The between-bottle homogeneity and within-bottle homogeneity were thoroughly evaluated with consistent results. The potential DNA degradation in transportation and shelf life were evaluated with an expiration period of at least 12 months. The property values of three CRMs (G6H1a, G6H1b, G6H1c) were given as (49.825 ± 0.448) g/kg, (9.967 ± 1.757) g/kg, and (4.986 ± 1.274 g/kg based on mass fraction ratio,...

Root angle has a major impact on acquisition of nutrients like phosphate that accumulate in topsoil and in many species; low phosphate induces shallower root growth as an adaptive response. Identifying genes and mechanisms controlling root angle is therefore of paramount importance to plant breeding. Here we show that the actin-binding protein Rice Morphology Determinant (RMD) controls root growth angle by linking actin filaments and gravity-sensing organelles termed statoliths. RMD is upregulated in response to low external phosphate and mutants lacking of RMD have steeper crown root growth angles that are unresponsive to phosphate levels. RMD protein localizes to the surface of statoliths, and rmd mutants exhibit faster gravitropic response owing to more rapid statoliths movement. We conclude that adaptive changes to root angle in response to external phosphate availability are RMD dependent, providing a potential target for breeders., The orientation of plant roots responds to gravity and influences nutrient acquisition. Here the authors show that the formin RMD buffers movement of specialized gravity-sensing organelles and report enhanced RMD expression during phosphate deficiency that could alter root angle to improve phosphate uptake.

Since early 2016, the Chinese goose industry has experienced severe outbreaks of gout; however, the etiological factor of the disease is still unclear. Here, we investigated the possible involvement of viral infection in the disease. Using sequence-independent PCR amplification, astrovirus sequences were generated from a gout case. Full-length genomic sequencing and sequence analysis of three goose astrovirus (GoAstV) strains revealed that they belong to a new avastrovirus most closely related to viruses classified within species Avastrovirus 3. The GoAstV was detected in 16/16 gout cases collected from two provinces, supporting a pathogenic role for the new avastrovirus.

Flower organ patterning is accomplished by spatial and temporal functioning of various regulatory genes. We previously reported that Oryza sativa VIN3-LIKE 2 (OsVIL2) induces flowering by mediating the trimethylation of Histone H3 on LFL1 chromatin. In this study, we report that OsVIL2 also plays crucial roles during spikelet development. Two independent lines of T-DNA insertional mutants in the gene displayed altered organ numbers and abnormal morphology in all spikelet organs. Scanning electron microscopy showed that osvil2 affected organ primordia formation during early spikelet development. Expression analysis revealed that OsVIL2 is expressed in all stages of the spikelet developmental. Transcriptome analysis of developing spikelets revealed that several regulatory genes involved in that process and the formation of floral organs were down-regulated in osvil2. These results suggest that OsVIL2 is required for proper expression of the regulatory genes that control floral organ number and morphology.

Aminoacyl-tRNA synthetases (aaRSs) have housekeeping roles in protein synthesis, but little is known about how these aaRSs are involved in organ development. Here, we report that a rice (Oryza sativa) glutamyl-tRNA synthetase (OsERS1) maintains proper somatic cell organization and limits the overproliferation of male germ cells during early anther development. The expression of OsERS1 is specifically detectable in meristematic layer 2-derived cells of the early anther, and osers1 anthers exhibit overproliferation and disorganization of layer 2-derived cells, producing fused lobes and extra germ cells in early anthers. The conserved biochemical function of OsERS1 in ligating glutamate to tRNAGlu is enhanced by its cofactor aaRS OsARC. Furthermore, metabolomics profiling revealed that OsERS1 is an important node for multiple metabolic pathways, indicated by the accumulation of amino acids and tricarboxylic acid cycle components in osers1 anthers. Notably, the anther defects of the osers1 mutant are causally associated with the abnormal accumulation of hydrogen peroxide, which can reconstitute the osers1 phenotype when applied to wild-type anthers. Collectively, these findings demonstrate how aaRSs affect male organ development in plants, likely through protein synthesis, metabolic homeostasis, and redox status.

Root traits such as root angle and hair length influence resource acquisition particularly for immobile nutrients like phosphorus (P). Here, we attempted to modify root angle in rice by disrupting the OsAUX1 auxin influx transporter gene in an effort to improve rice P acquisition efficiency. We show by X-ray microCT imaging that root angle is altered in the osaux1 mutant, causing preferential foraging in the top soil where P normally accumulates, yet surprisingly, P acquisition efficiency does not improve. Through closer investigation, we reveal that OsAUX1 also promotes root hair elongation in response to P limitation. Reporter studies reveal that auxin response increases in the root hair zone in low P environments. We demonstrate that OsAUX1 functions to mobilize auxin from the root apex to the differentiation zone where this signal promotes hair elongation when roots encounter low external P. We conclude that auxin and OsAUX1 play key roles in promoting root foraging for P in rice.

Multi-target, short time, and resource-affordable methodologies for the detection of multiple nucleic acids in a single, easy to operate test are urgently needed in disease diagnosis, microbial monitoring, genetically modified organism (GMO) detection, and forensic analysis. We have previously described the platform called CALM (Capillary Array-based Loop-mediated isothermal amplification for Multiplex visual detection of nucleic acids). Herein, we describe improved fabrication and performance processes for this platform. Here, we apply a small, ready-to-use cassette assembled by capillary array for multiplex visual detection of nucleic acids. The capillary array is pre-treated into a hydrophobic and hydrophilic pattern before fixing loop-mediated isothermal amplification (LAMP) primer sets in capillaries. After assembly of the loading adaptor, LAMP reaction mixture is loaded and isolated into each capillary, due to capillary force by a single pipetting step. The LAMP reactions are performed in parallel in the capillaries. The results are visually read out by illumination with a hand-held UV flashlight. Using this platform, we demonstrate monitoring of 8 frequently appearing elements and genes in GMO samples with high specificity and sensitivity. In summary, the platform described herein is intended to facilitate the detection of multiple nucleic acids. We believe it will be widely applicable in fields where high-throughput nucleic acid analysis is required.

RLKs in anther development. The cell-to-cell communication is essential for specifying different cell types during plant growth, development and adaption to the ever-changing environment. Plant male reproduction, in particular, requires the exquisitely synchronized development of different cell layers within the male tissue, the anther. Receptor-like kinases (RLKs) belong to a large group of kinases localized on the cell surfaces, perceiving extracellular signals and thereafter regulating intracellular processes. Here we update the role of RLKs in early anther development by defining the cell fate and anther patterning, responding to the changing environment and controlling anther carbohydrate metabolism. We provide speculation of the poorly characterized ligands and substrates of these RLKs. The conserved and diversified aspects underlying the function of RLKs in anther development are discussed.

In plants, normal anther and pollen development involves many important biological events and complex molecular regulatory coordination. Understanding gene regulatory relationships during male reproductive development is essential for fundamental biology and crop breeding. In this work, we developed a rice gene co-expression network for anther development (RiceAntherNet) that allows prediction of gene regulatory relationships during pollen development. RiceAntherNet was generated from 57 rice anther tissue microarrays across all developmental stages. The microarray datasets from nine rice male sterile mutants, including msp1-4, ostdl1a, gamyb-2, tip2, udt1-1, tdr, eat1-1, ptc1 and mads3-4, were used to explore and test the network. Among the changed genes, three clades showing differential expression patterns were constructed to identify genes associated with pollen formation. Many of these have known roles in pollen development, for example, seven genes in Clade 1 (OsABCG15, OsLAP5, OsLAP6, DPW, CYP703A3, OsNP1 and OsCP1) are involved in rice pollen wall formation. Furthermore, Clade 1 contained 12 genes whose predicted orthologs in Arabidopsis have been reported as key during pollen development and may play similar roles in rice. Genes in Clade 2 are expressed earlier than Clade 1 (anther stages 2-9), while genes in Clade 3 are expressed later (stages 10-12). RiceAntherNet serves as a valuable tool for identifying novel genes during plant anther and pollen development. A website is provided (https://www.cpib.ac.uk/anther/riceindex.html) to present the expression profiles for gene characterization. This will assist in determining the key relationships between genes, thus enabling characterization of critical genes associated with anther and pollen regulatory networks.

DNA markers play important roles in plant breeding and genetics. The Insertion/Deletion (InDel) marker is one kind of co-dominant DNA markers widely used due to its low cost and high precision. However, the canonical way of searching for InDel markers is time-consuming and labor-intensive. We developed an end-to-end computational solution (InDel Markers Development Platform, IMDP) to identify genome-wide InDel markers under a graphic pipeline environment. IMDP constitutes assembled genome sequences alignment pipeline (AGA-pipe) and next-generation re-sequencing data mapping pipeline (NGS-pipe). With AGA-pipe we are able to identify 12,944 markers between the genome of rice cultivars Nipponbare and 93-11. Using NGS-pipe, we reported 34,794 InDels from re-sequencing data of rice cultivars Wu-Yun-Geng7 and Guang-Lu-Ai4. Combining AGA-pipe and NGS-pipe, we developed 205,659 InDels in eight japonica and nine indica cultivars and 2,681 InDels showed a subgroup-specific pattern. Polymerase chain reaction (PCR) analysis of subgroup-specific markers indicated that the precision reached 90% (86 of 95). Finally, to make them available to the public, we have integrated the InDels/markers information into a website (Rice InDel Marker Database, RIMD, http://202.120.45.71/). The application of IMDP in rice will facilitate efficiency for development of genome-wide InDel markers, in addition it can be used in other species with reference genome sequences and NGS data.

A novel standard reference plasmid (pGEM-PAPAYA3) was constructed as a positive control and reference standard for event-specific qualitative and quantitative detection of genetically modified (GM) papaya (55-1, 16-0-1, and Huanong No.1). The plasmid pGEM-PAPAYA3 contained the specific fragments of papaya endogenous reference gene chymopapain and the 3 GM papaya events. The qualitative PCR assay using pGEM-PAPAYA3 was established with a limit of detection correlating to approximately 5–50 copies of papaya haploid genomes. In the quantitative PCR assay, the square regression coefficients (R2) ranged from 0.993 to 0.997. The standard deviation and relative standard deviation values for repeatability ranged from 0.04 to 0.25 and 0.05%–0.86%, respectively. The method was used to test 11 papaya products purchased from Thailand, China, the Philippines and the USA, and the results revealed 2 varieties of GM papaya in 5 of the 11 samples tested. These results indicate the developed detection methods with the standard reference plasmid are applicable for identifying 3 GM papaya events.

During reproductive development, rice plants develop unique flower organs which determine the final grain yield. OsMADS1, one of SEPALLATA-like MADS-box genes, has been unraveled to play critical roles in rice floral organ identity specification and floral meristem determinacy. However, the molecular mechanisms underlying interactions of OsMADS1 with other floral homeotic genes in regulating flower development remains largely elusive. In this work, we studied the genetic interactions of OsMADS1 with B-, C-, and D-class genes along with physical interactions among their proteins. We show that the physical and genetic interactions between OsMADS1 and OsMADS3 are essential for floral meristem activity maintenance and organ identity specification; while OsMADS1 physically and genetically interacts with OsMADS58 in regulating floral meristem determinacy and suppressing spikelet meristem reversion. We provided important genetic evidence to support the neofunctionalization of two rice C-class genes (OsMADS3 and OsMADS58) during flower development. Gene expression profiling and quantitative RT-PCR analyses further revealed that OsMADS1 affects the expression of many genes involved in floral identity and hormone signaling, and chromatin immunoprecipitation (ChIP)–PCR assay further demonstrated that OsMADS17 is a direct target gene of OsMADS1. Taken together, these results reveal that OsMADS1 has diversified regulatory functions in specifying rice floral organ and meristem identity, probably through its genetic and physical interactions with different floral homeotic regulators.

Ginseng (Panax ginseng), a valued medicinal herb, is a slow-growing plant that flowers after 3 years of growth with the formation of a solitary terminal umbel inflorescence. However, little is known about cytological events during ginseng reproduction, such as the development of the male organ, the stamen. To better understand the mechanism controlling ginseng male reproductive development, here, we investigated the inflorescence and flower structure of ginseng. Moreover, we performed cytological analysis of anther morphogenesis and showed the common and specialized cytological events including the formation of four concentric cell layers surrounding male reproductive cells followed by subsequent cell differentiation and degeneration of tapetal cells, as well as the formation of mature pollen grains via meiosis and mitosis during ginseng anther development. Particularly, our transverse section and microscopic observations showed that the ginseng tapetal layer exhibits obvious nonsynchronous cell division evidenced by the observation of one or two tapetal layers frequently observed in one anther lobe, suggesting the unique control of cell division. To facilitate the future study on ginseng male reproduction, we grouped the anther development into 10 developmental stages according to the characterized cytological events.

Ethnopharmacological relevance Paeonia suffruticosa Andrews (PSE) is a well-known Chinese medicine that has been widely used as an anti-tumor, anti-oxidative and anti-inflammatory agent. cis - and trans -gnetin H are two resveratrol oligomers isolated from the seeds of PSE. Although resveratrol is widely considered to be one of the most valuable natural chemopreventive agents and there are numerous studies on the antitumor activities of resveratrol, little is known about the antitumor properties of cis - and trans -gnetin H. Materials and methods The inhibitory effects of cis - and trans -gnetin H in different human cancer cell lines were assessed using fluorescent viability tests. Cytotoxicity in human lung and breast cancer cells was detected via nuclear condensation, cell permeability, and changes in the mitochondrial membrane potential (∆ψm). Apoptosis in human lung and breast cancer cells was assessed by flow cytometry, a luminescence assay and high-content screening analysis. Finally, a xenograft mice model was used to examine the efficacy of cis -gnetin H on lung tumors. Results cis - and trans -gnetin H have superior activity in inhibiting the proliferation of four human cancer cell lines, A549 (lung), BT20 (breast), MCF-7 (breast) and U2OS (osteosarcoma), and promote cell apoptosis, while having a minimal effect on two normal human epithelial cell lines, HPL1A (lung) and HMEC (breast) used as controls. cis - and trans -gnetin H promote apoptosis by releasing mitochondria cytochrome c , activating caspase 3/7 and inhibiting NF-κB activation. Flow cytometry analysis shows that cis - or trans -gnetin H arrested the cell cycle of cancer cells at the G0–G1 phase. Moreover, cis -gnetin H suppressed the growth of xenograft lung tumors in mice. Conclusion Collectively, our findings demonstrate the promise of the natural compounds cis - and trans -gnetin H as candidates for cancer chemotherapy agents.

The birth of new genes in genomes is an important evolutionary event. Several studies reveal that new genes in animals tend to be preferentially expressed in male reproductive tissues such as testis (Betrán et al., 2002; Begun et al., 2007; Dubruille et al., 2012), and thus an "out of testis" hypothesis for the emergence of new genes has been proposed (Vinckenbosch et al., 2006; Kaessmann, 2010). However, such phenomena have not been examined in plant species. Here, by employing a phylostratigraphic method, we dated the origin of protein-coding genes in rice and Arabidopsis thaliana and observed a number of young genes in both species. These young genes tend to encode short extracellular proteins, which may be involved in rapid evolving processes, such as reproductive barriers, species specification, and anti-microbial processes. Further analysis of transcriptome age indexes across different tissues revealed that male reproductive cells express a phylogenetically younger transcriptome than other plant tissues. Compared with sporophytic tissues, the young transcriptomes of the male gametophyte displayed greater complexity and diversity, which included a higher ratio of anti-sense and inter-genic transcripts, reflecting a pervasive transcription state that facilitated the emergence of new genes. Here, we propose that pollen may act as an "innovation incubator" for the birth of de novo genes. With cases of male-biased expression of young genes reported in animals, the "new genes out of the male" model revealed a common evolutionary force that drives reproductive barriers, species specification, and the upgrading of defensive mechanisms against pathogens.

Three divergent groups of duck astroviruses (DAstVs), namely DAstV-1, DAstV-2 (formerly duck hepatitis virus type 3) and DAstV-3 (isolate CPH), and other avastroviruses are known to infect domestic ducks. To provide more data regarding the molecular epidemiology of astroviruses in domestic ducks, we examined the prevalence of astroviruses in 136 domestic duck samples collected from four different provinces of China. Nineteen goose samples were also included. Using an astrovirus-specific reverse transcription-PCR assay, two groups of astroviruses were detected from our samples. A group of astroviruses detected from Pekin ducks, Shaoxing ducks and Landes geese were highly similar to the newly discovered DAstV-3. More interestingly, a novel group of avastroviruses, which we named DAstV-4, was detected in Pekin ducks. Following full-length sequencing and sequence analysis, the variation between DAstV-4 and other avastroviruses in terms of lengths of genome and internal component was highlighted. Sequence identity and phylogenetic analyses based on the amino acid sequences of the three open reading frames (ORFs) clearly demonstrated that DAstV-4 was highly divergent from all other avastroviruses. Further analyses showed that DAstV-4 shared low levels of genome identities (50-58%) and high levels of mean amino acid genetic distances in the ORF2 sequences (0.520-0.801) with other avastroviruses, suggesting DAstV-4 may represent an additional avastrovirus species although the taxonomic relationship of DAstV-4 to DAstV-3 remains to be resolved. The present works contribute to the understanding of epidemiology, ecology and taxonomy of astroviruses in ducks.

Transport of photoassimilates from leaf tissues (source regions) to the sink organs is essential for plant development. Here, we show that a phytohormone, the brassinosteroids (BRs) promotes pollen and seed development in rice by directly promoting expression of Carbon Starved Anther (CSA) which encodes a MYB domain protein. Over-expression of the BR-synthesis gene D11 or a BR-signaling factor OsBZR1 results in higher sugar accumulation in developing anthers and seeds, as well as higher grain yield compared with control non-transgenic plants. Conversely, knockdown of D11 or OsBZR1 expression causes defective pollen maturation and reduced seed size and weight, with less accumulation of starch in comparison with the control. Mechanically, OsBZR1 directly promotes CSA expression and CSA directly triggers expression of sugar partitioning and metabolic genes during pollen and seed development. These findings provide insight into how BRs enhance plant reproduction and grain yield in an important agricultural crop.

Isothermal DNA/RNA amplification techniques are the primary methodology for developing on-spot rapid nucleic acid amplification assays, and the loop-mediated isothermal amplification (LAMP) technique has been developed and applied in the detection of foodborne pathogens, plant/animal viruses, and genetically modified (GM) food/feed contents. In this study, one set of LAMP assays targeting on eight frequently used universal elements, marker genes, and exogenous target genes, such as CaMV35S promoter, FMV35S promoter, NOS, bar, cry1Ac, CP4 epsps, pat, and NptII, were developed for visual screening of GM contents in plant-derived food samples with high efficiency and accuracy. For these eight LAMP assays, their specificity was evaluated by testing commercial GM plant events and their limits of detection were also determined, which are 10 haploid genome equivalents (HGE) for FMV35S promoter, cry1Ac, and pat assays, as well as five HGE for CaMV35S promoter, bar, NOS terminator, CP4 epsps, and NptII assays. The screening applicability of these LAMP assays was further validated successfully using practical canola, soybean, and maize samples. The results suggested that the established visual LAMP assays are applicable and cost-effective for GM screening in plant-derived food samples.

Rice is an important food crop worldwide. Genomic research on global germplasm has theoretical and practical significances in the mining of favorable alleles and on genome-based molecular breeding, which are related to Chinese and global food security. Through the 3000 (3K) Rice Genome Project, we collected single nucleotide polymorphism (SNP) and insertion and deletion (InDel) genomic variation data for the 2859 rice genomes, and establish a comprehensive SNP and InDel sub-database for the Rice Functional Genomics-based Breeding (RFGB) Database. This sub-database is a global resource containing a polymorphism information retrieval function, a genome browser visualization system and a data export system for specific genomic regions, along with other tools. This study establishes an important platform for rice gene functional research and rice molecular breeding by genomic selection.

As more and more genetically modified (GM) crops are approved for commercialization and planting, safety issues of GM crops have become hot topics worldwide. For both regulatory and academic purposes, development of rapid, economic and effective on-site detection methods for GM components is indispensible. Up to now, the most effective and sensitive techniques used for GMO detection are based on polymerase chain reaction (PCR). PCR method needs expensive, heavy instruments and gel electrophoresis, therefore, it is commonly used in laboratory test, and unsuitable for on-site detection. Loop-mediated isothermal amplification (LAMP), an isothermal nucleic acid amplification technique, has been extensively used in many areas such as food safety and clinic diagnosis. Advantageous characteristics of LAMP, such as high specificity and sensitivity, simple operation, low cost, eye visualization, particularly free of special equipment, renders it with high potential to be used for GMO on-site detection. In this review, we summarized current status of the application of LAMP in GMO detection, and discussed possible improvements needed for its adaptability regarding to on-site GMO detection. Hopefully, the information present here would facilitate the practical risk assessment of GMO.

This work was supported by funds from the National Key Basic Research Developments Program, Ministry of Science and Technology, China (2013CB126902); National Transgenic Major Program Grant (2016ZX08009003-003-007); National Natural Science Foundation of China (31322040); China Innovative Research Team, Ministry of Education, and the Program of Introducing Talents of Discipline to Universities (111 Project, B14016); the Science and Technology Commission of Shanghai Municipality (grant no. 13JC1408200). Work in the Higgins laboratory is supported by the BBSRC.

Many monocot plants have high social and economic value. These include grasses such as rice (Oryza sativa), wheat (Triticum aestivum), and barley (Hordeum vulgare), which produce soft commodities for many food and beverage industries, and ornamental flowers such ase lily (Lilium longiflorum) and orchid (Oncidium Gower Ramsey), which represent an important component of international flower markets. There is constant pressure to improve the development and diversity of these species, with a significant emphasis on flower development, and this is particularly relevant considering the impact of changing environments on reproduction and thus yield. MADS-box proteins are a family of transcription factors that contain a conserved 60 amino acid MADS-box motif. In plants, attention has been devoted to characterization of this family due to their roles in inflorescence and flower development, which holds promise for the modification of floral architecture for plant breeding. This has been explored in diverse angiosperms, but particularly the dicot model Arabidopsis thaliana. The focus of this review is on the less well characterized roles of the MADS-box proteins in monocot flower development and how changes in MADS-box proteins throughout evolution may have contributed to creating a diverse range of flowers. Examining these changes within the monocots can identify the importance of certain genes and pinpoint those which might be useful in future crop improvement and breeding strategies.

Endogenous reference genes (ERG) and their derivate analytical methods are standard requirements for analysis of genetically modified organisms (GMOs). Development and validation of suitable ERGs is the primary step for establishing assays that monitoring the genetically modified (GM) contents in food/feed samples. Herein, we give a review of the ERGs currently used for GM wheat analysis, such as ACC1, PKABA1, ALMT1, and Waxy-D1, as well as their performances in GM wheat analysis. Also, we discussed one model for developing and validating one ideal RG for one plant species based on our previous research work.

Transcription factors regulate multiple networks, mediating the responses of organisms to stresses, including drought. Here, we investigated the role of the wheat transcription factor TaSHN1 in crop growth and drought tolerance. TaSHN1, isolated from bread wheat, was characterized for molecular interactions and functionality. The overexpression of TaSHN1 in wheat was followed by the evaluation of T2 and T3 transgenic lines for drought tolerance, growth, and yield components. Leaf surface changes were analysed by light microscopy, SEM, TEM, and GC-MS/GC-FID. TaSHN1 behaves as a transcriptional activator in a yeast transactivation assay and binds stress-related DNA cis-elements, determinants of which were revealed using 3D molecular modelling. The overexpression of TaSHN1 in transgenic wheat did not result in a yield penalty under the controlled plant growth conditions of a glasshouse. Transgenic lines had significantly lower stomatal density and leaf water loss and exhibited improved recovery after severe drought, compared with control plants. The comparative analysis of cuticular waxes revealed an increased accumulation of alkanes in leaves of transgenic lines. Our data demonstrate that TaSHN1 may operate as a positive modulator of drought stress tolerance. Positive attributes could be mediated through an enhanced accumulation of alkanes and reduced stomatal density.

Multiple-target plasmid DNA reference materials have been generated and utilized as good substitutes of matrix-based reference materials in the analysis of genetically modified organisms (GMOs). Herein, we report the construction of one multiple-target plasmid reference molecule, pCAN, which harbors eight GM canola event-specific sequences (RF1, RF2, MS1, MS8, Topas 19/2, Oxy235, RT73, and T45) and a partial sequence of the canola endogenous reference gene PEP. The applicability of this plasmid reference material in qualitative and quantitative PCR assays of the eight GM canola events was evaluated, including the analysis of specificity, limit of detection (LOD), limit of quantification (LOQ), and performance of pCAN in the analysis of various canola samples, etc. The LODs are 15 copies for RF2, MS1, and RT73 assays using pCAN as the calibrator and 10 genome copies for the other events. The LOQ in each event-specific real-time PCR assay is 20 copies. In quantitative real-time PCR analysis, the PCR efficiencies of all event-specific and PEP assays are between 91% and 97%, and the squared regression coefficients (R

The dynamics of metabolites from leaves to roots of Panax ginseng during development has revealed the tissue-specific and year-specific metabolic networks. Being an essential Oriental medicinal plant, ginseng (Panax ginseng Meyer) is a slow-growing perennial herb-accumulating pharmaceutically active metabolites such as ginsenosides in roots during growth. However, little is known about how ginseng plants survive in the harsh environments such as winter cold and summer heat for a longer period and accumulates those active metabolites as the plant grows. To understand the metabolic kinetics in both source and sink organs such as leaves and roots of ginseng plant, respectively, and to assess the changes in ginsenosides biosynthesis during ginseng growth, we investigated the metabolic profiles from leaves and roots of 1-, 4-, and 6-year-old field-grown ginseng plants. Using an integrated non-targeted metabolomic approach, we identified in total 348 primary and secondary metabolites, which provided us for the first time a global metabolomic assessment of ginseng during growth, and morphogenesis. Strikingly, the osmoprotectants and oxidized chemicals were highly accumulated in 4- and 6-year-old ginseng leaves suggested that ginseng develop a wide range of metabolic strategies to adapt unfavorable conditions as they mature. In 6-year-old plants, ginsenosides were decreased in leaves but increased in roots up to 1.2- to sixfold, supporting the view that there is a long-distance transport of ginsenosides from leaves to roots as ginseng plants mature. Our findings provide insights into the metabolic kinetics during the development of ginseng plant and this could complement the pharmacological importance of ginseng and its compounds according to their age.

Grasses display highly diversified inflorescence architectures that differ in the arrangement of spikelets and flowers and determine cereal yields. However, the molecular basis underlying grass inflorescence morphogenesis remains largely unknown. Here we investigate the role of a functionally diversified SEPALLATA MADS-box transcription factor, OsMADS34, in regulating rice (Oryza sativa L.) inflorescence and spikelet development. Microarray analysis showed that, at the very early stages of inflorescence formation, dysfunction of OsMADS34 caused altered expression of 379 genes that are associated with protein modification and degradation, transcriptional regulation, signaling and metabolism activity. Genetic analysis revealed that OsMADS34 controls different aspects of inflorescence structure, branching and meristem activity synergistically with LAX PANICLE1 (LAX1) and FLORAL ORGAN NUMBER4 (FON4), as evidenced by the enhanced phenotypes of osmads34 lax1 and osmads34 fon4 compared with the single mutants. Additionally, double mutant between osmads34 and the sterile lemma defective mutant elongated empty glume (ele) displayed an enhanced phenotype, that is, longer and wider sterile lemmas that were converted into lemma/palea-like organs, suggesting that ELE and OsMADS34 synergistically control the sterile lemma development. OsMADS34 may act together with OsMADS15 in controlling sterile lemma development. Collectively, these findings provide insights into the regulatory function of OsMADS34 in rice inflorescence and spikelet development.

Lipid and phenolic metabolism are important for pollen exine formation. In Arabidopsis, polyketide synthases (PKSs) are essential for both sporopollenin biosynthesis and exine formation. Here, we characterized the role of a polyketide synthase (OsPKS2) in male reproduction of rice (Oryza sativa). Recombinant OsPKS2 catalyzed the condensation of fatty acyl-CoA with malonyl-CoA to generate triketide and tetraketide α-pyrones, the main components of pollen exine. Indeed, the ospks2 mutant had defective exine patterning and was male sterile. However, the mutant showed no significant reduction in sporopollenin accumulation. Compared with the WT (wild type), ospks2 displayed unconfined and amorphous tectum and nexine layers in the exine, and less organized Ubisch bodies. Like the pksb/lap5 mutant of the Arabidopsis ortholog, ospks2 showed broad alterations in the profiles of anther-related phenolic compounds. However, unlike pksb/lap5, in which most detected phenolics were substantially decreased, ospks2 accumulated higher levels of phenolics. Based on these results and our observation that OsPKS2 is unable to fully restore the exine defects in the pksb/lap5, we propose that PKS proteins have functionally diversified during evolution. Collectively, our results suggest that PKSs represent a conserved and diversified biochemical pathway for anther and pollen development in higher plants.

In many plant species, male-sterile female lines with cytoplasmic male sterility (CMS) or nuclear-controlled environment-sensitive genic male sterility (EGMS) have long been used to efficiently produce hybrids that harness hybrid vigor or heterosis. However, the underlying molecular mechanisms for these applications have only recently been uncovered in a few species. We provide here an update on the understanding of cytoplasmic-nuclear communication based on the discovery of mitochondrial CMS genes and their corresponding nuclear fertility determinants. Recent findings that uncover diverse mechanisms such as epigenetic, transcriptional, and post-transcriptional controls of EGMS by temperature and photoperiod signals are also reviewed. Furthermore, translational research that applies basic knowledge of plant male fertility control to hybrid seed production practice is highlighted.

Loop-mediated isothermal amplification (LAMP) has been widely used in many fields of molecular diagnostics, including detection of genetically modified organisms (GMOs). Herein, we report a collaborative ring trial validation of three established visual LAMP assays targeting three common GM elements, namely CaMV35S promoter, FMV35S promoter and NOS terminator, respectively. The high specificity of each assay was confirmed in different GM events analyses, and the sensitivity of each was determined to be 10, 10, and 50 haploid genome equivalents (HGEs) for CaMV35S promoter, FMV35S promoter, and NOS terminator, respectively. The probability of detection was also determined based on specificity and sensitivity data from 10 participating laboratories that returned correct results for the practical sample tests. These results demonstrate that the three visual LAMP assays are sensitive and time-saving, with high application potential for on-spot testing and routine screening of GMOs.

In plants, geranylgeranyl diphosphate (GGPP) is produced by plastidic GGPP synthase (GGPPS) and serves as a precursor for vital metabolic branches, including chlorophyll, carotenoid, and gibberellin biosynthesis. However, molecular mechanisms regulating GGPP allocation among these biosynthetic pathways localized in the same subcellular compartment are largely unknown. We found that rice contains only one functionally active GGPPS, OsGGPPS1, in chloroplasts. A functionally active homodimeric enzyme composed of two OsGGPPS1 subunits is located in the stroma. In thylakoid membranes, however, the GGPPS activity resides in a heterodimeric enzyme composed of one OsGGPPS1 subunit and GGPPS recruiting protein (OsGRP). OsGRP is structurally most similar to members of the geranyl diphosphate synthase small subunit type II subfamily. In contrast to members of this subfamily, OsGRP enhances OsGGPPS1 catalytic efficiency and specificity of GGPP production on interaction with OsGGPPS1. Structural biology and protein interaction analyses demonstrate that affinity between OsGRP and OsGGPPS1 is stronger than between two OsGGPPS1 molecules in homodimers. OsGRP determines OsGGPPS1 suborganellar localization and directs it to a large protein complex in thylakoid membranes, consisting of geranylgeranyl reductase (OsGGR), light-harvesting-like protein 3 (OsLIL3), protochlorophyllide oxidoreductase (OsPORB), and chlorophyll synthase (OsCHLG). Taken together, genetic and biochemical analyses suggest OsGRP functions in recruiting OsGGPPS1 from the stroma toward thylakoid membranes, thus providing a mechanism to control GGPP flux toward chlorophyll biosynthesis.

Ethyl carbamate (EC), a multisite carcinogenic chemical causing tumors in various animal species, is probably carcinogenic to humans. However, information about the possible carcinogenic and toxicological effects of EC in humans is quite limited. Because EC is found in many dietary foods (such as fermented foods) and tobacco and its products, and exposure of humans to EC often occurs inevitably, its toxicological effects in humans need to be studied. This study was conducted to understand the metabolomic and transcriptomic changes in human hepatocellular carcinoma cells (HepG2) exposed to 100 mM EC for short term (4 h) and long term (12 h) period, respectively. The results revealed multiple influences of EC on the metabolome and transcriptome of HepG2 cells, which was exposure time-dependent and well correlated with the kinetic changes of cell viability and mortality. EC treatment affected multiple metabolic pathways, inducing oxidative stress, reducing detoxification capacity, depleting energy, decreasing reducing power, disrupting membrane integrity, and damaging DNA and protein. These metabolomic and transcriptomic biomarkers of EC on human cell metabolism identified in this study would facilitate further studies on the risk assessment and the mitigation of dietary EC.

Loss of function mutation of rice OsACOS12 impairs lipid metabolism-mediated anther cuticle and pollen wall formation, and interferes with tapetum programmed cell death, leading to male sterility. Acyl-CoA Synthetase (ACOS) is one of the enzymes activating fatty acids for various metabolic functions in plants. Here, we show that OsACOS12, an orthologue of Arabidopsis ACOS5 in rice, is crucial for rice fertility. Similar to acos5, osaocs12 mutant had no mature pollen. But unlike acos5, osaocs12 produced defective anthers lacking cutin and Ubisch bodies on the epidermal and inner surfaces, respectively, and delayed programmed cell death (PCD)-induced tapetum degradation. Those phenotypic changes were evident at stage 10, during which OsACOS12 had its maximum expression in tapetal cells and microspores. Chemical analysis revealed that the levels of anther cuticular lipid components (wax and cutin monomers) were significantly reduced in osaocs12, while the expression levels of three known lipid biosynthetic genes were unchanged. Recombinant OsACOS12 enzyme was shown to catalyze the conversion of C18:1 fatty acid to C18:1 CoA in vitro. Phylogenetic analysis indicated that OsACOS12 is an ancient and conserved enzyme associated with the plant’s colonization to earth. Collectively, our study suggests that OsACOS12 is an ancient enzyme participating in a conserved metabolic pathway for diversified biochemical functions to secure male reproduction in plants.

There is an urgent need for rapid, low-cost multiplex methodologies for the monitoring of genetically modified organisms (GMOs). Here, we report a C[combining low line]apillary A[combining low line]rray-based L[combining low line]oop-mediated isothermal amplification for M[combining low line]ultiplex visual detection of nucleic acids (CALM) platform for the simple and rapid monitoring of GMOs. In CALM, loop-mediated isothermal amplification (LAMP) primer sets are pre-fixed to the inner surface of capillaries. The surface of the capillary array is hydrophobic while the capillaries are hydrophilic, enabling the simultaneous loading and separation of the LAMP reaction mixtures into each capillary by capillary forces. LAMP reactions in the capillaries are then performed in parallel, and the results are visually detected by illumination with a hand-held UV device. Using CALM, we successfully detected seven frequently used transgenic genes/elements and five plant endogenous reference genes with high specificity and sensitivity. Moreover, we found that measurements of real-world blind samples by CALM are consistent with results obtained by independent real-time PCRs. Thus, with an ability to detect multiple nucleic acids in a single easy-to-operate test, we believe that CALM will become a widely applied technology in GMO monitoring.

Small RNAs, including microRNAs (miRNAs), are abundant in plants and play key roles in controlling plant development and physiology. miRNAs regulate the expression of the target genes involved in key plant processes. Due to functional redundancy among miRNA family members in plants, an ideal approach to silence the expression of all members simultaneously, for their functional characterization, is desirable. Target mimic (TM) was the first approach to achieve this goal. Short tandem target mimic (STTM) is a potent approach complementing TM for silencing miRNAs in plants. STTMs have been successfully used in dicots to block miRNA functions. Here, we describe in detail the protocol for designing STTM construct to block miRNA functions in rice. Such approach can be applied to silence miRNAs in other monocots as well.

Endogenous reference genes (ERG) and their derivate analytical methods are standard requirements for analysis of genetically modified organisms (GMOs). Development and validation of suitable ERGs is the primary step for establishing assays that monitoring the genetically modified (GM) contents in food/feed samples. Herein, we give a review of the ERGs currently used for GM wheat analysis, such as ACC1, PKABA1, ALMT1, and Waxy-D1, as well as their performances in GM wheat analysis. Also, we discussed one model for developing and validating one ideal RG for one plant species based on our previous research work.

OsMADS32 is a monocot specific MIKC(c) type MADS-box gene that plays an important role in regulating rice floral meristem and organs identity, a crucial process for reproductive success and rice yield. However, its underlying mechanism of action remains to be clarified. Here, we characterized a hypomorphic mutant allele of OsMADS32/CFO1, cfo1-3 and identified its function in controlling rice flower development by bioinformatics and protein-protein interaction analysis. The cfo1-3 mutant produces defective flowers, including loss of lodicule identity, formation of ectopic lodicule or hull-like organs and decreased stamen number, mimicking phenotypes related to the mutation of B class genes. Molecular characterization indicated that mis-splicing of OsMADS32 transcripts in the cfo1-3 mutant resulted in an extra eight amino acids in the K-domain of OsMADS32 protein. By yeast two hybrid and bimolecular fluorescence complementation assays, we revealed that the insertion of eight amino acids or deletion of the internal region in the K1 subdomain of OsMADS32 affects the interaction between OsMADS32 with PISTILLATA (PI)-like proteins OsMADS2 and OsMADS4. This work provides new insight into the mechanism by which OsMADS32 regulates rice lodicule and stamen identity, by interaction with two PI-like proteins via its K domain.

Rice (Oryza sativa L.) MADS3 transcription factor regulates the homeostasis of reactive oxygen species (ROS) during late anther development, and one MADS3 mutant, mads3-4, has defective anther walls, aborted microspores and complete male sterility. Here, we report the untargeted metabolomic analysis of both wild type and mads3-4 mature anthers. Mutation of MADS3 led to an unbalanced redox status and caused oxidative stress that damages lipid, protein, and DNA. To cope with oxidative stress in mads3-4 anthers, soluble sugars were mobilized and carbohydrate metabolism was shifted to amino acid and nucleic acid metabolism to provide substrates for the biosynthesis of antioxidant proteins and the repair of DNA. Mutation of MADS3 also affected other aspects of rice anther development such as secondary metabolites associated with cuticle, cell wall, and auxin metabolism. Many of the discovered metabolic changes in mads3-4 anthers were corroborated with changes of expression levels of corresponding metabolic pathway genes. Altogether, this comparative metabolomic analysis indicated that MADS3 gene affects rice anther development far beyond the ROS homeostasis regulation.

Soybean [Glycine max (L.) Merr.] is one of the world's major crops, and soybean seeds are a rich and important resource for proteins and oils. While "omics" studies, such as genomics, transcriptomics, and proteomics, have been widely applied in soybean molecular research, fewer metabolomic studies have been conducted for large-scale detection of low molecular weight metabolites, especially in soybean seeds. In this study, we investigated the seed metabolomes of 29 common soybean cultivars through combined gas chromatography-mass spectrometry and ultra-performance liquid chromatography-tandem mass spectrometry. One hundred sixty-nine named metabolites were identified and subsequently used to construct a metabolic network of mature soybean seed. Among the 169 detected metabolites, 104 were found to be significantly variable in their levels across tested cultivars. Metabolite markers that could be used to distinguish genetically related soybean cultivars were also identified, and metabolite-metabolite correlation analysis revealed some significant associations within the same or among different metabolite groups. Findings from this work may potentially provide the basis for further studies on both soybean seed metabolism and metabolic engineering to improve soybean seed quality and yield.

Anther cuticle and pollen exine act as protective envelopes for the male gametophyte or pollen grain, but the mechanism underlying the synthesis of these lipidic polymers remains unclear. Previously, a tapetum-expressed CYP703A3, a putative cytochrome P450 fatty acid hydroxylase, was shown to be essential for male fertility in rice (Oryza sativa L.). However, the biochemical and biological roles of CYP703A3 has not been characterized. Here, we observed that cyp703a3-2 caused by one base insertion in CYP703A3 displays defective pollen exine and anther epicuticular layer, which differs from Arabidopsis cyp703a2 in which only defective pollen exine occurs. Consistently, chemical composition assay showed that levels of cutin monomers and wax components were dramatically reduced in cyp703a3-2 anthers. Unlike the wide range of substrates of Arabidopsis CYP703A2, CYP703A3 functions as an in-chain hydroxylase only for a specific substrate, lauric acid, preferably generating 7-hydroxylated lauric acid. Moreover, chromatin immunoprecipitation and expression analyses revealed that the expression of CYP703A3 is directly regulated by Tapetum Degeneration Retardation, a known regulator of tapetum PCD and pollen exine formation. Collectively, our results suggest that CYP703A3 represents a conserved and diversified biochemical pathway for in-chain hydroxylation of lauric acid required for the development of male organ in higher plants.

The plant hormone auxin plays a central role in plant growth and development. Auxin transport and signaling depend on actin organization. Despite its functional importance, the mechanistic link between actin filaments (F-actin) and auxin intracellular signaling remains unclear. Here, we report that the actin-organizing protein Rice Morphology Determinant (RMD), a type II formin from rice (Oryza sativa), provides a key link. Mutants lacking RMD display abnormal cell growth and altered configuration of F-actin array direction. The rmd mutants also exhibit an inhibition of auxin-mediated cell elongation, decreased polar auxin transport, altered auxin distribution gradients in root tips, and suppression of plasma membrane localization of auxin transporters O. sativa PIN-FORMED 1b (OsPIN1b) and OsPIN2 in root cells. We demonstrate that RMD is required for endocytosis, exocytosis, and auxin-mediated OsPIN2 recycling to the plasma membrane. Moreover, RMD expression is directly regulated by heterodimerized O. sativa auxin response factor 23 (OsARF23) and OsARF24, providing evidence that auxin modulates the orientation of F-actin arrays through RMD. In support of this regulatory loop, osarf23 and lines with reduced expression of both OsARF23 and OsARF24 display reduced RMD expression, disrupted F-actin organization and cell growth, less sensitivity to auxin response, and altered auxin distribution and OsPIN localization. Our findings establish RMD as a crucial component of the auxin-actin self-organizing regulatory loop from the nucleus to cytoplasm that controls rice cell growth and morphogenesis.

A novel virus was detected from diseased ducks and completely determined. The virus was shown to have a picornavirus-like genome layout. Interestingly, the genome contained a total of up to six 2As, including four 2As (2A1–2A4) each having an NPGP motif, an AIG1-like 2A5, and a parechovirus-like 2A6. The 5′UTR was predicted to possess a hepacivirus/pestivirus-like internal ribosome entry site (IRES). However, the subdomain IIIe consisted of a 3 nt stem and five unpaired bases, distinct from those found in all other HP-like IRESs. The virus was most closely related to duck hepatitis A virus, with amino acid identities of 37.7 %, 39 % and 43.7 % in the P1, P2 and P3 regions, respectively. Based on these investigations, together with phylogenetic analyses, the virus could be considered as the founding member of a novel picornavirus genus that we tentatively named ‘Aalivirus’, with ‘Aalivirus A’ as the type species.