RALF1-FERONIA complex affects splicing dynamics to modulate stress responses and growth in plants
Wang et al. found that the interaction of the extracellular rapid alkalinization FACTOR 1 (RALF1) peptide with its receptor FERONIA (FER) triggered a rapid and massive RNA AS response by interacting with and phosphorylating glycine-rich RNA binding protein7 (GRP7) to elevate GRP7 nuclear accumulation in Arabidopsis thaliana. FER-dependent GRP7 phosphorylation enhanced its mRNA binding ability and its association with the spliceosome component U1-70K to enable splice site selection, modulating dynamic AS. Genetic reversal of a RALF1-FER–dependent splicing target partly rescued mutants deficient in GRP7. AS of GRP7 itself induced nonsense-mediated decay feedback to the RALF1-FER-GRP7 module, fine-tuning stress responses, and cell growth.
Functions of Anionic Lipids in Plants
Using the localization of each anionic lipid and its related metabolic enzymes as starting points, Noack and Jallais summarize their roles within the different compartments of the endomembrane system and address their associated developmental and physiological consequences.
Annual Review of Plant Biology
Soil fungal networks maintain local dominance of ectomycorrhizal trees
Liang et al. show that tree seedlings that interact via root-associated fungal hyphae with soils beneath neighbouring adult trees grow faster and have greater survival than seedlings that are isolated from external fungal mycelia, but these effects are observed for species possessing ectomycorrhizas (ECM) and not arbuscular mycorrhizal (AM) fungi. Moreover, survival of naturally-regenerating AM seedlings over ten years is negatively related to the density of surrounding conspecific plants, while survival of ECM tree seedlings displays positive density dependence over this interval, and AM seedling roots contain greater abundance of pathogenic fungi than roots of ECM seedlings.
Convergent molecular evolution among ash species resistant to the emerald ash borer
Recent studies show that molecular convergence plays an unexpectedly common role in the evolution of convergent phenotypes. Kelly et al. exploited this phenomenon to find candidate loci underlying resistance to the emerald ash borer (EAB, Agrilus planipennis), the United States’ most costly invasive forest insect to date, within the pan-genome of ash trees (the genus Fraxinus). They show that EAB-resistant taxa occur within three independent phylogenetic lineages.
Nature Ecology & Evolution
Auxin export from proximal fruits drives arrest in temporally competent inflorescences
Ware et al. provide a framework for the communication previously inferred in the global proliferative arrest model. They show that the end-of-flowering in Arabidopsis is not ‘global’ and does not occur synchronously between branches, but rather that the arrest of each inflorescence is a local process, driven by auxin export from fruit proximal to the inflorescence apex. Furthermore, they show that inflorescences are competent for arrest only once they reach a certain developmental age.
Pervasive shifts in forest dynamics in a changing world
McDowell et al. review recent progress in understanding the drivers of forest dynamics and how these are interacting and changing in the context of global climate change. The authors show that shifts in forest dynamics are already occurring, and the emerging pattern is that global forests are tending toward younger stands with faster turnover as old-growth forest with stable dynamics are dwindling.
Selaginella was hyperdiverse already in the Cretaceous
"Selaginella is notorious for the small morphological differences seen among many species," say Schmidt et al. but they find that it's not a new trait for the genus.
Loss of function of the Pad-1 aminotransferase gene, which is involved in auxin homeostasis, induces parthenocarpy in Solanaceae plants
Matsuo et al. report a parthenocarpic eggplant mutant, pad-1, which accumulates high levels of auxin in the ovaries. Map-based cloning showed that the wild-type (WT) Pad-1 gene encoded an aminotransferase with similarity to Arabidopsis VAS1 gene, which is involved in auxin homeostasis. Recombinant Pad-1 protein catalyzed the conversion of indole-3-pyruvic acid (IPyA) to tryptophan (Trp), which is a reverse reaction of auxin biosynthetic enzymes, tryptophan aminotransferases (TAA1/TARs). The RNA level of Pad-1 gene increased during ovary development and reached its highest level at anthesis stage in WT. This suggests that the role of Pad-1 in WT unpollinated ovary is to prevent overaccumulation of IAA resulting in precocious fruit-set.
Management performance mapping and the value of information for regional prioritization of management interventions
Policymakers and donors often need to identify the locations and settings where technologies are most likely to have important effects, to increase the benefits from agricultural development or extension efforts. Higher quality information may help to target the high-payoff locations. The value of information (VOI) in this context is formalized by evaluating the results of decision making guided by a set of information compared to the results of acting without taking the information into account. Buddenhagen et al. present a framework for management performance mapping that includes evaluating the VOI for decision making about geographic priorities in regional intervention strategies, in case studies of Andean and Kenyan potato seed systems.
A multidimensional framework for measuring biotic novelty: How novel is a community?
Schittko et al. propose the Biotic Novelty Index (BNI), an intuitive and flexible multidimensional measure that combines (a) functional differences between native and non‐native introduced species with (b) temporal dynamics of species introductions. They show that the BNI is an additive partition of Rao's quadratic entropy, capturing the novel interaction component of the community's functional diversity. Simulations show that the index varies predictably with the relative amount of functional novelty added by recently arrived species, and they illustrate the need to provide an additional standardized version of the index.
Global Change Biology