Differential phosphopeptide expression in a benign breast tissue, and triple-negative primary and metastatic breast cancer tissues from the same African-American woman by LC-LTQ/FT-ICR mass spectrometry

African-American women have a higher risk for developing triple-negative breast cancer (TNBC). Lacking the expression of receptors for estrogen and progesterone, and without human epidermal growth factor 2 receptor gene amplification, TNBC is a very aggressive type of breast cancer with a high likelihood of metastasis and recurrence. Specific therapeutic targets for this aggressive disease remain to be identified. Phosphorylation, a post-translational modification that adds one or more phosphate groups to a protein, plays a key role in the activation and deactivation of a protein’s cellular function. Here, we report the first systematic phosphoproteomic analysis of a benign breast tissue, a primary breast cancer tissue, and a metastatic breast cancer tissue from the same African-American woman. Differential phosphoprotein levels were measured with reversed-phase nano-liquid chromatography coupled to a hybrid linear quadrupole ion trap/Fourier transform ion cyclotron resonance mass spectrometer (LC-LTQ/FT-ICR MS). Five proteins were found to be highly phosphorylated in the metastatic site whereas six proteins were highly phosphorylated in the cancer site of the TNBC patient. Identified phosphoproteins are known to be involved in breast cancer signal transduction pathways and these results may identify new diagnostic and therapeutic targets for TNBC.     

Nuclear-cytoplasmic interactions reduce male fertility in hybrids of Arabidopsis lyrata subspecies

We examined the level of postzygotic reproductive isolation in F(1) and F(2) hybrids of reciprocal crosses between the Arabidopsis lyrata subspecies lyrata (North American) and petraea (European). Our main results are: first, the percentage of fertile pollen was significantly reduced in the F(1) and F(2) compared to the parental populations. Second, mean pollen fertility differed markedly between reciprocal crosses: 84% in the F(2) with ssp. lyrata cytoplasm and 61% in the F(2) with ssp. petraea cytoplasm. Third, 17% of the F(2) with ssp. petraea cytoplasm showed male sterility (produced less than 30 pollen grains in our subsample). The hybrids were female fertile. We used QTL mapping to find the genomic regions that determine pollen fertility and that restore cytoplasmic male sterility (CMS). In the F(2) with ssp. lyrata cytoplasm, an epistatic pair of QTLs was detected. In the reciprocal F(2) progeny, four QTLs demonstrated within-population polymorphism for hybrid male sterility. In addition, in the F(2) with ssp. petraea cytoplasm, there was a strong male fertility restorer locus on chromosome 2 where a cluster of CMS restorer gene-related PPR genes have been found in A. lyrata. Our results underline the importance of cytonuclear interactions in understanding genetics of the early stages of speciation.     

Are you more than the sum of your parents’ genes? Phenotypic plasticity in a clonal vertebrate and F1 hybrids of its parental species

All known vertebrate clones have originated from hybridization events and some have produced distinct evolutionary lineages via hybrid speciation. Amazon mollies (Poecilia formosa) present an excellent study system to investigate how clonal species have adapted to heterogeneous environments because they are the product of a single hybridization event between male sailfin mollies (Poecilia latipinna) and female Atlantic mollies (Poecilia mexicana). Here, we ask whether the hybrid species differs from the combination of its parental species’ genes in its plastic response to different environments. Using a three-way factorial design, we exposed neonates produced by Amazon mollies and reciprocal F1 hybrid crosses to different thermal (24°C and 29°C) and salinity (0/2, 12, and 20 ppt) regimes. We measured various ontogenetic and life history characteristics across the life span of females. Our major results were as follows: (1) Reaction norms of growth and maturation to temperature and salinity are quite similar between the two hybrid crosses; (2) Amazon molly reaction norms were qualitatively different than the P. latipinna male and P. mexicana female (L×M) hybrids for the ontogenetic variables; (3) Amazon molly reaction norms in reproductive traits were also quite different from L×M hybrids; and (4) The reaction norms of net fertility were very different between Amazon mollies and L×M hybrids. We conclude that best locale for Amazon mollies is not the best locale for hybrids, which suggests that Amazon mollies are not just an unmodified mix of parental genes but instead have adapted to the variable environments in which they are found. Hybridization resulting in asexuality may represent an underappreciated mechanism of speciation because the unlikely events required to produce such hybrids rarely occur and is dependent upon the genetic distance between parental species.     

Combined effects of drought stress and psyllid herbivory on the invasive weed Scotch broom,Cytisus scoparius

Increases in the frequency and duration of droughts under global climate change could have implications for plant–insect interactions, and could either increase or decrease the effects of weed biological control agents. In this study, we used greenhouse and field experiments to examine the impacts of drought stress on the abundance and impacts of the adventive psyllid Arytainilla spartiophila Forster (Hemiptera: Psyllidae, Arytaininae) on its target weed Scotch broom, Cytisus scoparius (L.) Link (Fabaceae), in California, USA. The psyllid impacted plant growth in both field and greenhouse experiments, whereas drought stress affected plant growth in the greenhouse only, suggesting that other factors besides water availability may be more limiting for plants in the field. Effects on psyllid survival were consistent with the plant vigor hypothesis, which predicts that herbivores will perform better on vigorously growing plants; psyllid numbers were lower on drought-stressed plants in the greenhouse and were correlated with plant growth in both the greenhouse and the field. In the greenhouse, the combined effects of the psyllid and drought stress were additive, indicating that the effects of the psyllid were consistent across unstressed and drought-stressed plants. Although the psyllid is unlikely to control Scotch broom on its own, results suggest that it may work in conjunction with drought stress to suppress Scotch broom.     

Review – Treatment of Helicobacter pylori infection 2020

This review summarizes important studies regarding Helicobacter pylori therapy published from April 2019 to April 2020. The main themes that emerge involve studies assessing antibiotic resistance, and there is also growing momentum behind the utility of vonoprazan as an alternative to proton pump inhibitor (PPI) therapy and also bismuth‐based regimens as a first‐line regimen. Antibiotic resistance is rising wherever it is being assessed, and clarithromycin resistance in particular has reached a point where it may no longer be a viable therapy without previous testing in many regions of the world. The evidence for the efficacy of a bismuth‐based quadruple therapy as a first‐line therapy is now very clearly established, and there is substantial evidence that it is the best performing first‐line therapy. The utility of vonoprazan as an alternative to PPI therapy, especially in resistant and difficult‐to‐treat groups, has also been considered in great detail this year, and it may offer an opportunity in the near future to reduce the problem of antibiotic resistance.     

Life cycle sustainability assessment of autonomous heavy‐duty trucks

Connected and automated vehicles (CAVs) are emerging technologies expected to bring important environmental, social, and economic improvements in transportation systems. Given their implications in terms of air quality and sustainable and safer movement of goods, heavy‐duty trucks (HDTs), carrying the majority of U.S. freight, are considered an ideal domain for the application of CAV technology. An input–output (IO) model is developed based on the Eora database—a detailed IO database that consists of national IO tables, covering almost the entire global economy. Using the Eora‐based IO model, this study quantifies and assesses the environmental, economic, and social impacts of automated diesel and battery electric HDTs based on 20 macro‐level indicators. The life cycle sustainability performances of these HDTs are then compared to that of a conventional diesel HDT. The study finds an automated diesel HDT to cause 18% more fatalities than an automated electric HDT. The global warming potential (GWP) of automated diesel HDTs is estimated to be 4.7 thousand metric tons CO₂‐eq. higher than that of automated electric HDTs. The health impact costs resulting from an automated diesel HDT are two times higher than that of an automated electric HDT. Overall, the results also show that automation brings important improvements to the selected sustainability indicators of HDTs such as global warming potential, life cycle cost, GDP, decrease in import, and increase in income. The findings also show that there are significant trade‐offs particularly between mineral and fossil resource losses and environmental gains, which are likely to complicate decision‐making processes regarding the further development and commercialization of the technology.     

Migratory divides coincide with reproductive barriers across replicated avian hybrid zones above the Tibetan Plateau

Migratory divides are proposed to be catalysts for speciation across a diversity of taxa. However, it is difficult to test the relative contributions of migratory behaviour vs. other divergent traits to reproductive isolation. Comparing hybrid zones with and without migratory divides offers a rare opportunity to directly examine the contribution of divergent migratory behaviour to reproductive barriers. We show that across replicate sampling transects of two pairs of barn swallow (Hirundo rustica) subspecies, strong reproductive isolation coincided with a migratory divide spanning 20 degrees of latitude. A third subspecies pair exhibited no evidence for a migratory divide and hybridised extensively. Within migratory divides, overwintering habitats were associated with assortative mating, implicating a central contribution of divergent migratory behaviour to reproductive barriers. The remarkable geographic coincidence between migratory divides and genetic breaks supports a long‐standing hypothesis that the Tibetan Plateau is a substantial barrier contributing to the diversity of Siberian avifauna.     

Biotechnological mechanism for improving plant remobilization of phosphorus during leaf senescence

Phosphorus enrichment of aquatic ecosystems through diffuse source pollution is an ongoing issue worldwide. A potential solution lies in the use of fast‐growing, multipurpose feedstocks, such as trees, to limit the flow of phosphorus into riparian areas through luxury consumption. However, the perennial nature of trees and their use of leaves as storage organs for excess phosphorus may reduce the effectiveness of contaminant removal during periods of leaf abscission. In an attempt to improve phosphorus remobilization during autumnal senescence, transgenic hybrid poplar P39 (Populus alba × Populus grandidentata) and Arabidopsis thaliana harbouring a constitutively expressed low‐affinity potato phosphate transporter (35S::StPht1‐1) were generated using Agrobacterium‐mediated transformation. For both species, the highest expressing 35S::StPht1‐1 lines were grown alongside wild‐type plants and subjected to increasing phosphate applications. StPht1‐1 expression in A. thaliana led to a reduction in biomass when grown under high‐phosphate conditions and had no effect on phosphate remobilization during senescence. In contrast, StPht1‐1 constitutive expression in P39 resulted in increased leaf phosphate content in the highest expressing transgenic line and minimal to no effect on P resorption efficiency. Surprisingly, sulphate resorption showed the greatest improvement in all three transgenic poplar lines, displaying a 31%–37% increase in resorption efficiency. These results highlight the complexity of nutrient resorption mechanisms in plants.     

Large‐Grained Perovskite Films Enabled by One‐Step Meniscus‐Assisted Solution Printing of Cross‐Aligned Conductive Nanowires for Biodegradable Flexible Solar Cells

Increasing performance demand associated with the short lifetime of consumer electronics has triggered fast growth in electronic waste, leading to serious ecological challenges worldwide. Herein, a robust strategy for judiciously constructing flexible perovskite solar cells (PSCs) that can be conveniently biodegraded is reported. The key to this strategy is to capitalize on meniscus‐assisted solution printing (MASP) as a facile means of yielding cross‐aligned silver nanowires in one‐step, which are subsequently impregnated in a biodegradable elastomeric polyester. Intriguingly, the as‐crafted hybrid biodegradable electrode greatly constrains the solvent evaporation of the perovskite precursor solution, thereby generating fewer nuclei and in turn resulting in the deposition of a large‐grained dense perovskite film that exhibits excellent optoelectronic properties with a power conversion efficiency of 17.51% in PSCs. More importantly, the hybrid biodegradable electrode‐based devices also manifest impressive robustness against mechanical deformation and can be thoroughly biodegraded after use. These results signify the great potential of MASP for controllably assembling aligned conductive nanomaterials for biodegradable electrodes. As such, it represents an important endeavor toward environmentally friendly, multifunctional and flexible electronic, optoelectronic, photonic, and sensory materials and devices.