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Contemporary Earth crises are challenging ideologies that enthrone humans at the center of existence and separate from nature, problematizing common notions of sustainability. Further inquiry, particularly sustainability of what and for whom, requires decentering the human experience toward other-than-human beings (e.g., plants and animals). In this article, we, as the Kinship Circle book club, share reflections from our monthly dialogue with the five-part book series Kinship: Belonging in a World of Relations, built on a foundation of partnership experiences with the Keweenaw Bay Indian Community Lake Superior Band of Ojibwa. Together, we discuss three major departures from our previous modes of thought at the individual, community, and global levels. First, as students, mentors, and relatives to many, we aim for (research) practices that affirm relationships to place, an approach we understand as remembering what it means to be human. Second, to rebuild shared responsibilities across communities of many kinds, we move beyond an anthropomorphization debate toward “animism," recognizing the sentience and autonomy of other-than-human beings on Earth. Third, in support of a transformative and collective human ethic, we hope to contribute to restoring relationships with the many that gift us life, using connections between migration, justice, and introduced species. Finally, we present a practical Kinship Circle framework for applying these concepts in educational settings. Our conclusion provides central kinship lessons for decentering humans in the sustainability sciences, rooted in humility, responsibility, and an Earth-centered ethics. 

Abstract P4 ATPases (i.e., lipid flippases) are eukaryotic enzymes that transport lipids across membrane bilayers. In plants, P4 ATPases are named Aminophospholipid ATPases (ALAs) and are organized into five phylogenetic clusters. Here we generated an Arabidopsis mutant lacking all five cluster‐2 ALAs (ala8/9/10/11/12), which is the most highly expressedALAsubgroup in vegetative tissues. Plants harboring the quintuple knockout (KO) show rosettes that are 2.2‐fold smaller and display chlorotic lesions. A similar but less severe phenotype was observed in anala10/11double KO. The growth and lesion phenotypes ofala8/9/10/11/12mutants were reversed by expressing aNahGtransgene, which encodes an enzyme that degrades salicylic acid (SA). A role for SA in promoting the lesion phenotype was further supported by quantitative PCR assays showing increased mRNA abundance for an SA‐biosynthesis geneISOCHORISMATE SYNTHASE 1(ICS1) and two SA‐responsive genesPATHOGENESIS‐RELATED GENE 1(PR1) andPR2.Lesion phenotypes were also reversed by growing plants in liquid media containing either low calcium (~0.1 mM) or high nitrogen concentrations (~24 mM), which are conditions known to suppress SA‐dependent autoimmunity. Yeast‐based fluorescent lipid uptake assays revealed that ALA10 and ALA11 display overlapping substrate specificities, including the transport of LysoPC signaling lipids. Together, these results establish that the biochemical functions of ALA8–12 are at least partially overlapping, and that deficiencies in cluster‐2 ALAs result in an SA‐dependent autoimmunity phenotype that has not been observed for flippase mutants with deficiencies in otherALAclusters. 

Abstract Background Despite the development of safe and effective vaccines, effective treatments for COVID-19 disease are still urgently needed. Several antiviral drugs have shown to be effective in reducing progression of COVID-19 disease. Methods In the present work, we use an agent-based mathematical model to assess the potential population impact of the use of antiviral treatments in four countries with different demographic structure and current levels of vaccination coverage: Kenya, Mexico, United States (US) and Belgium. We analyzed antiviral effects on reducing hospitalization and death, and potential antiviral effects on reducing transmission. For each country, we varied daily treatment initiation rate (DTIR) and antiviral effect in reducing transmission (AVT). Results Irrespective of location and AVT, widespread antiviral treatment of symptomatic adult infections (20% DTIR) prevented the majority of COVID-19 deaths, and recruiting 6% of all adult symptomatic infections daily reduced mortality by over 20% in all countries. Furthermore, our model projected that targeting antiviral treatment to the oldest age group (65 years old and older, DTIR of 20%) can prevent over 30% of deaths. Our results suggest that early antiviral treatment (as soon as possible after inception of infection) is needed to mitigate transmission, preventing 50% more infections compared to late treatment (started 3 to 5 days after symptoms onset). Our results highlight the synergistic effect of vaccination and antiviral treatment: as the vaccination rate increases, antivirals have a larger relative impact on population transmission. Finally, our model projects that even in highly vaccinated populations, adding antiviral treatment can be extremely helpful to mitigate COVID-19 deaths. Conclusions These results suggest that antiviral treatments can become a strategic tool that, in combination with vaccination, can significantly reduce COVID-19 hospitalizations and deaths and can help control SARS-CoV-2 transmission. 

Land plants evolved to quickly sense and adapt to temperature changes, such as hot days and cold nights. Given that calcium (Ca 2+ ) signaling networks are implicated in most abiotic stress responses, heat-triggered changes in cytosolic Ca 2+ were investigated in Arabidopsis leaves and pollen. Plants were engineered with a reporter called CGf, a ratiometric, genetically encoded Ca 2+ reporter with an m C herry reference domain fused to an intensiometric Ca 2+ reporter G CaMP6 f . Relative changes in [Ca 2+ ] cyt were estimated based on CGf’s apparent K D around 220 nM. The ratiometric output provided an opportunity to compare Ca 2+ dynamics between different tissues, cell types, or subcellular locations. In leaves, CGf detected heat-triggered cytosolic Ca 2+ signals, comprised of three different signatures showing similarly rapid rates of Ca 2+ influx followed by differing rates of efflux (50% durations ranging from 5 to 19 min). These heat-triggered Ca 2+ signals were approximately 1.5-fold greater in magnitude than blue light-triggered signals in the same leaves. In contrast, growing pollen tubes showed two different heat-triggered responses. Exposure to heat caused tip-focused steady growth [Ca 2+ ] cyt oscillations to shift to a pattern characteristic of a growth arrest (22%), or an almost undetectable [Ca 2+ ] cyt (78%). Together, these contrasting examples of heat-triggered Ca 2+ responses in leaves and pollen highlight the diversity of Ca 2+ signals in plants, inviting speculations about their differing kinetic features and biological functions. 

Abstract Generating cellular Ca2+ signals requires coordinated transport activities from both Ca2+ influx and efflux pathways. In Arabidopsis (Arabidopsis thaliana), multiple efflux pathways exist, some of which involve Ca2+-pumps belonging to the Autoinhibited Ca2+-ATPase (ACA) family. Here, we show that ACA1, 2, and 7 localize to the endoplasmic reticulum (ER) and are important for plant growth and pollen fertility. While phenotypes for plants harboring single-gene knockouts (KOs) were weak or undetected, a triple KO of aca1/2/7 displayed a 2.6-fold decrease in pollen transmission efficiency, whereas inheritance through female gametes was normal. The triple KO also resulted in smaller rosettes showing a high frequency of lesions. Both vegetative and reproductive phenotypes were rescued by transgenes encoding either ACA1, 2, or 7, suggesting that all three isoforms are biochemically redundant. Lesions were suppressed by expression of a transgene encoding NahG, an enzyme that degrades salicylic acid (SA). Triple KO mutants showed elevated mRNA expression for two SA-inducible marker genes, Pathogenesis-related1 (PR1) and PR2. The aca1/2/7 lesion phenotype was similar but less severe than SA-dependent lesions associated with a double KO of vacuolar pumps aca4 and 11. Imaging of Ca2+ dynamics triggered by blue light or the pathogen elicitor flg22 revealed that aca1/2/7 mutants display Ca2+ transients with increased magnitudes and durations. Together, these results indicate that ER-localized ACAs play important roles in regulating Ca2+ signals, and that the loss of these pumps results in male fertility and vegetative growth deficiencies.