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<jats:p>Humans have cultivated grasses for food, feed, beverages, and construction materials for millennia. Grasses also dominate the landscape in vast parts of the world, where they have adapted morphologically and physiologically, diversifying to form ~12,000 species. Sequences of hundreds of grass genomes show that they are essentially collinear; nonetheless, not all species have the same complement of genes. Here, we focus on the molecular, cellular, and developmental bases of grain yield and dispersal—traits that are essential for domestication. Distinct genes, networks, and pathways were selected in different crop species, reflecting underlying genomic diversity. With increasing genomic resources becoming available in nondomesticated species, we anticipate advances in coming years that illuminate the ecological and economic success of the grasses.</jats:p>

<jats:p> Grasslands store approximately one third of the global terrestrial carbon stocks and can act as an important soil carbon sink. Recent studies show that plant diversity increases soil organic carbon (SOC) storage by elevating carbon inputs to belowground biomass and promoting microbial necromass contribution to SOC storage. Climate change affects grassland SOC storage by modifying the processes of plant carbon inputs and microbial catabolism and anabolism. Improved grazing management and biodiversity restoration can provide low-cost and/or high-carbon-gain options for natural climate solutions in global grasslands. The achievable SOC sequestration potential in global grasslands is 2.3 to 7.3 billion tons of carbon dioxide equivalents per year (CO <jats:sub>2</jats:sub> e year <jats:sup>−1</jats:sup> ) for biodiversity restoration, 148 to 699 megatons of CO <jats:sub>2</jats:sub> e year <jats:sup>−1</jats:sup> for improved grazing management, and 147 megatons of CO <jats:sub>2</jats:sub> e year <jats:sup>−1</jats:sup> for sown legumes in pasturelands. </jats:p>

<jats:p>Seagrasses are remarkable plants that have adapted to live in a marine environment. They form extensive meadows found globally that bioengineer their local environments and preserve the coastal seascape. With the increasing realization of the planetary emergency that we face, there is growing interest in using seagrasses as a nature-based solution for greenhouse gas mitigation. However, seagrass sensitivity to stressors is acute, and in many places, the risk of loss and degradation persists. If the ecological state of seagrasses remains compromised, then their ability to contribute to nature-based solutions for the climate emergency and biodiversity crisis remains in doubt. We examine the major ecological role that seagrasses play and how rethinking their conservation is critical to understanding their part in fighting our planetary emergency.</jats:p>

<jats:p> Highlights from the <jats:italic>Science</jats:italic> family of journals </jats:p>

<jats:p>Editors’ selections from the current scientific literature</jats:p>

<jats:p> Kynurenic acid (KynA) is tissue protective in cardiac, cerebral, renal, and retinal ischemia models, but the mechanism is unknown. KynA can bind to multiple receptors, including the aryl hydrocarbon receptor, the a7 nicotinic acetylcholine receptor (a7nAChR), multiple ionotropic glutamate receptors, and the orphan G protein–coupled receptor GPR35. Here, we show that GPR35 activation was necessary and sufficient for ischemic protection by KynA. When bound by KynA, GPR35 activated G <jats:sub>i</jats:sub> - and G <jats:sub>12/13</jats:sub> -coupled signaling and trafficked to the outer mitochondria membrane, where it bound, apparantly indirectly, to ATP synthase inhibitory factor subunit 1 (ATPIF1). Activated GPR35, in an ATPIF1-dependent and pertussis toxin–sensitive manner, induced ATP synthase dimerization, which prevented ATP loss upon ischemia. These findings provide a rationale for the development of specific GPR35 agonists for the treatment of ischemic diseases. </jats:p>

<jats:p> Meiosis, at the transition between diploid and haploid life cycle phases, is accompanied by reprograming of cell division machinery and followed by a transition back to mitosis. We show that, in <jats:italic>Arabidopsis</jats:italic> , this transition is driven by inhibition of translation, achieved by a mechanism that involves processing bodies (P-bodies). During the second meiotic division, the meiosis-specific protein THREE-DIVISION MUTANT 1 (TDM1) is incorporated into P-bodies through interaction with SUPPRESSOR WITH MORPHOGENETIC EFFECTS ON GENITALIA 7 (SMG7). TDM1 attracts eIF4F, the main translation initiation complex, temporarily sequestering it in P-bodies and inhibiting translation. The failure of <jats:italic>tdm1</jats:italic> mutants to terminate meiosis can be overcome by chemical inhibition of translation. We propose that TDM1-containing P-bodies down-regulate expression of meiotic transcripts to facilitate transition of cell fates to postmeiotic gametophyte differentiation. </jats:p>

<jats:p>Genetic admixture is central to primate evolution. We combined 50 years of field observations of immigration and group demography with genomic data from ~9 generations of hybrid baboons to investigate the consequences of admixture in the wild. Despite no obvious fitness costs to hybrids, we found signatures of selection against admixture similar to those described for archaic hominins. These patterns were concentrated near genes where ancestry is strongly associated with gene expression. Our analyses also show that introgression is partially predictable across the genome. This study demonstrates the value of integrating genomic and field data for revealing how “genomic signatures of selection” (e.g., reduced introgression in low-recombination regions) manifest in nature; moreover, it underscores the importance of other primates as living models for human evolution.</jats:p>

<jats:p>Individual cells make decisions that are adapted to their internal state and surroundings, but how cells can reliably do this remains unclear. To study the information processing capacity of human cells, we conducted multiplexed quantification of signaling responses and markers of the cellular state. Signaling nodes in a network displayed adaptive information processing, which led to heterogeneous growth factor responses and enabled nodes to capture partially nonredundant information about the cellular state. Collectively, as a multimodal percept this gives individual cells a large information processing capacity to accurately place growth factor concentration within the context of their cellular state and make cellular state–dependent decisions. Heterogeneity and complexity in signaling networks may have coevolved to enable specific and context-aware cellular decision-making in a multicellular setting.</jats:p>

<jats:p> Carbenes are highly enabling reactive intermediates that facilitate a diverse range of otherwise inaccessible chemistry, including small-ring formation and insertion into strong σ bonds. To access such valuable reactivity, reagents with high entropic or enthalpic driving forces are often used, including explosive (diazo) or unstable ( <jats:italic>gem</jats:italic> -dihalo) compounds. Here, we report that common aldehydes are readily converted (via stable α-acyloxy halide intermediates) to electronically diverse (donor or neutral) carbenes to facilitate &gt;10 reaction classes. This strategy enables safe reactivity of nonstabilized carbenes from alkyl, aryl, and formyl aldehydes via zinc carbenoids. Earth-abundant metal salts [iron(II) chloride (FeCl <jats:sub>2</jats:sub> ), cobalt(II) chloride (CoCl <jats:sub>2</jats:sub> ), copper(I) chloride (CuCl)] are effective catalysts for these chemoselective carbene additions to σ and π bonds. </jats:p>