The conversion of CO2 with CH4 into liquid fuels and chemicals in a single‐step catalytic process that bypasses the production of syngas remains a challenge. In this study, liquid fuels and chemicals (e.g., acetic acid, methanol, ethanol, and formaldehyde) were synthesized in a one‐step process from CO2 and CH4 at room temperature (30 °C) and atmospheric pressure for the first time by using a novel plasma reactor with a water electrode. The total selectivity to oxygenates was approximately 50–60 %, with acetic acid being the major component at 40.2 % selectivity, the highest value reported for acetic acid thus far. Interestingly, the direct plasma synthesis of acetic acid from CH4 and CO2 is an ideal reaction with 100 % atom economy, but it is almost impossible by thermal catalysis owing to the significant thermodynamic barrier. The combination of plasma and catalyst in this process shows great potential for manipulating the distribution of liquid chemical products in a given process.

More than 87% of flowering plant species are animal-pollinated [1] and produce floral scents and other signals to attract pollinators. These floral cues may however also attract antagonistic visitors, including herbivores [2]. The dilemma is exacerbated when adult insects pollinate the same plant that their larvae consume. It remains largely unclear how plants maximize their fitness under these circumstances. Here we show that in the night-flowering wild tobacco Nicotiana attenuata, the emission of a sesquiterpene, (E)-α-bergamotene, in flowers increases adult Manduca sexta moth-mediated pollination success, while the same compound in leaves is known to mediate indirect defense against M. sexta larvae [3, 4]. Forward and reverse genetic analyses demonstrated that both herbivory-induced and floral (E)-α-bergamotene are regulated by the expression of a monoterpene-synthase-derived sesquiterpene synthase (NaTPS38). The expression pattern of NaTPS38 also accounts for variation in (E)-α-bergamotene emission among natural accessions. These results highlight that differential expression of a single gene that results in tissue-specific emission of one compound contributes to resolving the dilemma for plants when their pollinators are also herbivores. Furthermore, this study provides genetic evidence that pollinators and herbivores interactively shape the evolution of floral signals and plant defense.

Snapdragon (Antirrhinum majus L.), a member of the Plantaginaceae family, is an important model for plant genetics and molecular studies on plant growth and development, transposon biology and self-incompatibility. Here we report a near-complete genome assembly of A. majus cultivar JI7 (A. majus cv.JI7) comprising 510 Megabases (Mb) of genomic sequence and containing 37,714 annotated protein-coding genes. Scaffolds covering 97.12% of the assembled genome were anchored on eight chromosomes. Comparative and evolutionary analyses revealed that a whole-genome duplication event occurred in the Plantaginaceae around 46–49 million years ago (Ma). We also uncovered the genetic architectures associated with complex traits such as flower asymmetry and self-incompatibility, identifying a unique duplication of TCP family genes dated to around 46–49 Ma and reconstructing a near-complete ψS-locus of roughly 2 Mb. The genome sequence obtained in this study not only provides a representative genome sequenced from the Plantaginaceae but also brings the popular plant model system of Antirrhinum into the genomic age.

Canine parvovirus (CPV) is highly contagious and is a major cause of haemorrhagic enteritis and myocarditis in dogs. We investigated the genetic variation of emerging CPV strains by sequencing 64 CPV VP2 genes from 216 clinical samples of dogs from Heilongjiang, Jilin, Liaoning, Shandong and Hebei in 2014. Genetic analysis revealed that CPV-2b was predominant in Hebei and CPV-2a was predominant in the other four provinces. In addition, a CPV-2c strain has emerged in Shandong province. All samples had a Ser-Ala substitution at residue 297 and an Ile-Arg substitution at residue 324. Interestingly, in five separate canine samples, we found a mutation of Gln370 to Arg, until now detected only in isolates from pandas. The phylogenetic analysis showed clear distinctions between epidemic isolates and vaccine strains and between Chinese CPV-2c strains and CPV-2c strains found in other countries. Monitoring recent incidence of CPV strains enables evaluation and implementation of disease control strategies.

The self-incompatibility (SI) system with the broadest taxonomic distribution in angiosperms is based on multiple S-locus F-box genes (SLFs) tightly linked to an S-RNase termed type-1. Multiple SLFs collaborate to detoxify nonself S-RNases while being unable to detoxify self S-RNases. However, it is unclear how such a system evolved, because in an ancestral system with a single SLF, many nonself S-RNases would not be detoxified, giving low cross-fertilization rates. In addition, how the system has been maintained in the face of whole-genome duplications (WGDs) or lost in other lineages remains unclear. Here we show that SLFs from a broad range of species can detoxify S-RNases from Petunia with a high detoxification probability, suggestive of an ancestral feature enabling cross-fertilization and subsequently modified as additional SLFs evolved. We further show, based on its genomic signatures, that type-1 was likely maintained in many lineages, despite WGD, through deletion of duplicate S-loci. In other lineages, SI was lost either through S-locus deletions or by retaining duplications. Two deletion lineages regained SI through type-2 (Brassicaceae) or type-4 (Primulaceae), and one duplication lineage through type-3 (Papaveraceae) mechanisms. Thus, our results reveal a highly dynamic process behind the origin, maintenance, loss, and regain of SI.

S-RNase-based self-incompatibility (SI) is an intraspecific reproductive barrier to prevent self-fertilization found in many species of the Solanaceae, Plantaginaceae and Rosaceae. In this system, S-RNase and SLF/SFB (S-locus F-box) genes have been shown to control the pistil and pollen SI specificity, respectively. Recent studies have shown that the SLF functions as a substrate receptor of a SCF (Skp1/Cullin1/F-box)-type E3 ubiquitin ligase complex to target S-RNases in Solanaceae and Plantaginaceae, but its role in Rosaceae remains largely undefined. Here we report the identification of two pollen-specific SLF-interacting Skp1-like (SSK) proteins, PbSSK1 and PbSSK2, in Pyrus bretschneideri from the tribe Pyreae of Rosaceae. Both yeast two-hybrid and pull-down assays demonstrated that they could connect PbSLFs to PbCUL1 to form a putative canonical SCF(SLF) (SSK/CUL1/SLF) complex in Pyrus. Furthermore, pull-down assays showed that the SSK proteins could bind SLF and CUL1 in a cross-species manner between Pyrus and Petunia. Additionally, phylogenetic analysis revealed that the SSK-like proteins from Solanaceae, Plantaginaceae and Rosaceae form a monoclade group, hinting their shared evolutionary origin. Taken together, with the recent identification of a canonical SCF(SFB) complex in Prunus of the tribe Amygdaleae of Rosaceae, our results show that a conserved canonical SCF(SLF/SFB) complex is present in Solanaceae, Plantaginaceae and Rosaceae, implying that S-RNase-based self-incompatibility shares a similar molecular and biochemical mechanism.

Potato is the third most important staple food crop. To address challenges associated with global food security, a hybrid potato breeding system, aimed at converting potato from a tuber-propagated tetraploid crop into a seed-propagated diploid crop through crossing inbred lines, is under development. However, given that most diploid potatoes are self-incompatible, this represents a major obstacle which needs to be addressed in order to develop inbred lines. Here, we report on a self-compatible diploid potato, RH89-039-16 (RH), which can efficiently induce a mating transition from self-incompatibility to self-compatibility, when crossed to self-incompatible lines. We identify the S-locusinhibitor (Sli) gene in RH, capable of interacting with multiple allelic variants of the pistil-specific S-ribonucleases (S-RNases). Further, Sli gene functions like a general S-RNase inhibitor, to impart SC to RH and other self-incompatible potatoes. Discovery of Sli now offers a path forward for the diploid hybrid breeding program.

In flowering plants, intraspecific mate preference is frequently related to mating systems: the rejection of self pollen in self-incompatible (SI) plants that prevents inbreeding is one of the best described examples. However, in other mating systems, more nuanced patterns of pollen rejection occur. In the self-compatible (SC) Nicotiana attenuata, in which SI is not found and all crosses are compatible, certain pollen genotypes are consistently selected in mixed pollinations. However, the molecular mechanisms of this polyandrous mate selection remain unknown. Style-expressed NaS-like-RNases and pollen-expressed NaSLF-like genes, homologous to SI factors in Solanaceae, were identified and examined for a role in N. attenuata's mate selection. A comparison of two NaS-like-RNases and six NaSLF-like genes among 26 natural accessions revealed specific combinations of co-expression and direct protein-protein interactions. To evaluate their role in mate selection, we silenced the expression of specific NaS-like-RNases and NaSLF-like proteins and conducted diagnostic binary mixed pollinations and mixed pollinations with 14 different non-self pollen donors. Styles expressing particular combinations of NaS-like-RNases selected mates from plants with corresponding NaS-like-RNase expression patterns, while styles lacking NaS-like-RNase expression were non-selective in their fertilizations, which reflected the genotype ratios of pollen mixtures deposited on the stigmas. DNA methylation could account for some of the observed variation in stylar NaS-like-RNase patterns. We conclude that the S-RNase-SLF recognition mechanism plays a central role in polyandrous mate selection in this self-compatible species. These results suggest that after the SI-SC transition, natural variation of SI homologous genes was repurposed to mediate intraspecific mate selection.