The growing expansion range of drug resistant parasitic nematode populations threatens the sustainability of ruminant farming worldwide. In this context, nutraceuticals, i.e. feed that would both fulfil dietary requirements while ensuring parasite control, would contribute to increase farming sustainability in developed and low resource settings. In this study, we characterized the anthelmintic potential of lupin seed extracts against major ruminant trichostrongylids, i.e. H. contortus and T. circumcincta. Our observations showed that total seed extracts from commercially available lupin varieties significantly inhibited larval migration. This anthelmintic effect was sustained on multidrug resistant field isolate and across parasite species and was mediated by the seed alkaloid content. Analytical chemistry revealed a set of four lupanine and sparteine-derivatives with anthelmintic activity and electrophysiology assays on recombinant nematode acetylcholine receptors suggested an antagonistic mode of action for lupin alkaloids. While commercial lupin seeds did not exert direct anthelmintic effect in H. contortus infected lupin-fed ewes and goats, it significantly dampened blood production losses suffered by goats. Lupin seed extracts hence provide a working basis for the development of novel anthelmintic compounds able to break drug resistance in the field, while they could be used to increase the resilience of infected dairy ruminants.

The gametophytic maternal effect mutant medea ( mea ) shows aberrant growth regulation during embryogenesis in Arabidopsis thaliana . Embryos derived from mea eggs grow excessively and die during seed desiccation. Embryo lethality is independent of the paternal contribution and gene dosage. The mea phenotype is consistent with the parental conflict theory for the evolution of parent-of-origin–specific effects. MEA encodes a SET domain protein similar to Enhancer of zeste , a member of the Polycomb group. In animals, Polycomb group proteins ensure the stable inheritance of expression patterns through cell division and regulate the control of cell proliferation.

In flowering plants, signaling between the male pollen tube and the synergid cells of the female gametophyte is required for fertilization. In the Arabidopsis thaliana mutant feronia ( fer ), fertilization is impaired; the pollen tube fails to arrest and thus continues to grow inside the female gametophyte. FER encodes a synergid-expressed, plasma membrane–localized receptor-like kinase. We found that the FER protein accumulates asymmetrically in the synergid membrane at the filiform apparatus. Interspecific crosses using pollen from Arabidopsis lyrata and Cardamine flexuosa on A. thaliana stigmas resulted in a fer -like phenotype that correlates with sequence divergence in the extracellular domain of FER. Our findings show that the female control of pollen tube reception is based on a FER -dependent signaling pathway, which may play a role in reproductive isolation barriers.

Summary: Directional transport of the phytohormone auxin is required for the establishment and maintenance of plant polarity, but the underlying molecular mechanisms have not been fully elucidated. Plant homologs of human multiple drug resistance/P‐glycoproteins (MDR/PGPs) have been implicated in auxin transport, as defects in MDR1 (AtPGP19) and AtPGP1 result in reductions of growth and auxin transport in Arabidopsis (atpgp1, atpgp19), maize (brachytic2) and sorghum (dwarf3). Here we examine the localization, activity, substrate specificity and inhibitor sensitivity of AtPGP1. AtPGP1 exhibits non‐polar plasma membrane localization at the shoot and root apices, as well as polar localization above the root apex. Protoplasts from Arabidopsis pgp1 leaf mesophyll cells exhibit reduced efflux of natural and synthetic auxins with reduced sensitivity to auxin efflux inhibitors. Expression of AtPGP1 in yeast and in the standard mammalian expression system used to analyze human MDR‐type proteins results in enhanced efflux of indole‐3‐acetic acid (IAA) and the synthetic auxin 1‐naphthalene acetic acid (1‐NAA), but not the inactive auxin 2‐NAA. AtPGP1‐mediated efflux is sensitive to auxin efflux and ABC transporter inhibitors. As is seen in planta, AtPGP1 also appears to mediate some efflux of IAA oxidative breakdown products associated with apical sites of high auxin accumulation. However, unlike what is seen in planta, some additional transport of the benzoic acid is observed in yeast and mammalian cells expressing AtPGP1, suggesting that other factors present in plant tissues confer enhanced auxin specificity to PGP‐mediated transport.

We generated and characterized greater than 500 Drosophila strains that carry single copies of a novel P-element enhancer detector. In the majority of the strains, the beta-galactosidase reporter gene in the P-transposon responds to nearby transcriptional regulatory sequences in the genome. A remarkable diversity of spatially and temporally regulated staining patterns is observed in embryos carrying different insertions. We selected numerous strains as markers for different embryonic organs, tissues, and cells. Many of these strains should allow the study of complex developmental processes, such as nervous system development, which have not been convenient to analyze previously. Also, we present genetic evidence that some of the detected regulatory elements control nearby Drosophila genes. In light of our results, we discuss the diversity and complexity of cis-acting regulatory elements in the genome and the general applications of the enhancer detector method for the study of Drosophila development.

Fungal Invasion or Pollination?: When pollen finds a compatible flower, it grows a pollen tube which must find the egg cell and release the sperm it carries. In searching for genes that affect pollen tubes in Arabidopsis , Kessler et al. (p. 968 ; see the Perspective by Govers and Angenent ) found a gene previously implicated in susceptibility to powdery mildew infection (the NTA gene). The NTA gene encodes a seven-pass transmembrane protein, which, in combination with a receptor-like kinase called Fer, is needed for successful pollen tube growth; both sets of proteins are also needed for successful powdery mildew invasion. These processes hence share common mechanisms of cell invasion, but where they diverge is in the outcome: embryogenesis or pathogenesis.