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Julius Sachs (1868): The father of plant physiology
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The year 2018 marks the 150th anniversary of the first publication of Julius von Sachs' (1832–1897) Lehrbuch der Botanik (Textbook of Botany), which provided a comprehensive summary of what was then known about the plant sciences. Three years earlier, in 1865, Sachs produced the equally impressive Handbuch der Experimental‐Physiologie der Pflanzen (Handbook of Experimental Plant Physiology), which summarized the state of knowledge in all aspects of the discipline known today as plant physiology. Both of these books provided numerous insights based on Sachs' seminal experiments. By virtue of a reliance on detailed empirical observation and the rigorous application of chemical and physical principles, it is fair to say that the publication of these two monumental works marked the beginning of what can be called “modern‐day” plant science. Moreover, Sachs' Lehrbuch der Botanik prefigured the ascendance of plant molecular biology and the systems biology of photoautotrophic organisms. Regrettably, many of the insights of this great scientist have been forgotten by the generations who followed. It is only fitting, therefore, that the anniversary of the publication of the Lehrbuch der Botanik and the career of “the father of plant physiology” should be honored and reviewed, particularly because Sachs established the physiology of green organisms as an integral branch of botany and incorporated a Darwinian perspective into plant biology. Here we highlight key insights, with particular emphasis on Sachs' detailed discussion of sexual reproduction at the cellular level and his endorsement of Darwinian evolution.
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... Many new biological discoveries were being made in Europe, especially in Germany. Wilhelm Hofmeister's important works on the fertilisation of the egg and the formation of the embryo in flowering plants were published at around the same time as pioneering studies of cell plastids and mitosis by Hugo von Mohl, Eduard Strasburger and other researchers of cell biology (Hofmeister 1862;Campbell 1925;Kaplan & Cooke 1996;Gunning et al. 2006;Kutschera & Niklas 2018). British botanists relied heavily on received knowledge of these findings, drawing on English translations of German publications, notably the translation in 1862 of Hofmeister's Higher Cryptogamia (described as an "immortal work" by Thiselton-Dyer 1925), Julius von Sachs' Textbook of Botany (first English translation 1875) and later Eduard Adolf Strasburger's Textbook of Botany (first English translation 1898) and Gottlieb Haberlandt's Physiological Plant Anatomy (Haberlandt 1914, though the first English translation was published in 1898). ...
Kew’s Jodrell Laboratory was established in 1876 as a centre for botanical research in disciplines including plant physiology, anatomy and embryology, palaeobotany and mycology. Despite relatively little available funding, its location in one of the world’s largest botanic gardens and close to several well-curated plant collections has ensured its continued existence for almost a century and a half. Under the far-sighted leadership of Kew’s second Director, Joseph Dalton Hooker, the Jodrell Laboratory was established to coincide with Thomas Henry Huxley’s pioneering course at the Normal School of Science in London. Funded by a generous private donation, the Laboratory complemented and augmented the programme in taxonomy and systematics already established in Kew’s Herbarium, and provided a broader educational and research base to explore contemporary laboratory-based discoveries in fields such as physiology and lifecycles (sometimes termed the “New Botany”). The Jodrell Laboratory represents one of the world’s first non-university affiliated laboratories and has spawned several “spin-off” facilities such as the Laboratory of Plant Pathology and the Millennium Seed Bank. This paper traces its early influence as an important centre for research in palaeobotany and plant systematics, its subsequent decline during the inter-war years, and a relatively dynamic period of innovative research following the construction of a new building on the same site.
... In his pioneering 1868 Lehrbuch der Botanik (Textbook on Botany) Julius Sachs, often considered to be the father of plant physiology (Kutschera and Niklas 2018), noted that 'the absorption of water through the roots is also confined to certain limits of temperature... Tobacco plant and Gourd [sic] no longer absorb sufficient water to replace a small loss by evaporation in a moist soil of from 3 to 5 • C' (Sachs 1868). At the time, Sachs also noted that these low temperatures are limiting to other processes in plants such as the growth of green tissue or the exchange of oxygen and carbon dioxide. ...
This scientific commentary refers to `Negative effects of low root temperatures on water and carbon relations in temperate tree seedlings assessed by dual isotopic labelling' by Wang and Hoch (doi: 10.1093/treephys/tpac005).
In his pioneering 1868 Lehrbuch der Botanik (Textbook on Botany) Julius Sachs, often considered to be the father of plant physiology (Kutschera and Niklas 2018), noted that ‘the absorption of water through the roots is also confined to certain limits of temperature... Tobacco plant and Gourd [sic] no longer absorb sufficient water to replace a small loss by evaporation in a moist soil of from 3 to 5 °C’ (Sachs 1868). At the time, Sachs also noted that these low temperatures are limiting to other processes in plants such as the growth of green tissue or the exchange of oxygen and carbon dioxide. With considerable hindsight, we now know that water uptake is inextricably linked to turgor pressure and thus essential for cell expansion (Lockhart 1965). As such, turgor is a major limiting factor in tree growth and scaling-up its effects on forest biomass production is key to carbon sink and climate modeling (Friedlingstein et al. 2020, Cabon and Anderegg 2022). Yet, global models still overwhelmingly rely on ambient air rather than soil temperatures for their modeling even though soils show negative temperature offsets from recorded air temperatures from April to August in boreal and temperate zones, and nearly year round in the tropical forested regions of the globe (Lembrechts et al. 2022). These differences are highly dependent on both anthropogenic land use and climate-driven changes in ground cover (Lembrechts and Nijs 2020). Clearly, more attention needs to be given to the effects of low soil temperatures on plant roots and how they may impact these tree productivity models and, thus, projected climate change simulations.
... Over the past 15 years or so, there has been a heated debate on the unsuspected capacities of plants, with some authors taking up the hypothesis of their intelligence. 22,26,[73][74][75][76][77] In 2005, Stefano Mancuso and František Baluška, building on the work of intellectual forebears such as Wilhelm Pfeffer, Charles Darwin, Jagadis Chandra Bose or Julius von Sachs, 78,79 and following the discovery in plants of a large number of characteristics found in the neuronal system of animals, proposed the concept of 'plant neurobiology'. 34 This initiative very quickly led to a strong controversy. ...
Before the upheaval brought about by phylogenetic classification, classical taxonomy separated living beings into two distinct kingdoms, animals and plants. Rooted in ‘naturalist’ cosmology, Western science has built its theoretical apparatus on this dichotomy mostly based on ancient Aristotelian ideas. Nowadays, despite the adoption of the Darwinian paradigm that unifies living organisms as a kinship, the concept of the “scale of beings” continues to structure our analysis and understanding of living species. Our aim is to combine developments in phylogeny, recent advances in biology, and renewed interest in plant agency to craft an interdisciplinary stance on the living realm. The lines at the origin of plant or animal have a common evolutionary history dating back to about 3.9 Ga, separating only 1.6 Ga ago. From a phylogenetic perspective of living species history, plants and animals belong to sister groups. With recent data related to the field of Plant Neurobiology, our aim is to discuss some socio-cultural obstacles, mainly in Western naturalist epistemology, that have prevented the integration of living organisms as relatives, while suggesting a few avenues inspired by practices principally from other ontologies that could help overcome these obstacles and build bridges between different ways of connecting to life.
... 38 In two articles dedicated to Winslow Briggs on the occasion of his 90th birthday, the authors argued that "Briggs serves as a role model to what every biologist should aspire". 39,40 Together with his wife, Ann, the lab-scientist Briggs was a volunteer at the Henry W. Coe State Park close to San José, California, so that his early interest in the study of plants and animals in natural ecosystems continued until the end of his life 41 Winslow Briggs died on Feb. 11 at Stanford University Medical Center at the age of 90 years and 10 months. He is survived by his wife of 63 years, whom he met while they were students at Harvard University in Cambridge/Massachusetts, and by his daughters Marion, Lucia and Caroline, as well as four grandchildren and one great-grandchild. ...
The American biologist Winslow Russel Briggs (1928–2019) was a global leader in plant physiology, genetics and photobiology. In this contribution, we try to share our knowledge of the remarkable career of this outstanding scientist. After earning his PhD at Harvard (Cambridge, Massachusetts), he started his independent research program at Stanford University (California). Among many major contributions was his elegant experiment that conclusively demonstrated the role of auxin transport in the phototropic bending response of grass coleoptiles. During subsequent years as Professor of biology at Harvard University, Briggs focused on phytochrome and photomorphogenesis. In 1973, he re-located to Stanford to become Director of the Department of Plant Biology, Carnegie Institution for Science, and faculty member in the Biology Department at Stanford University. After his retirement (1993), he continued his research on “light and plant development” as an emeritus at Carnegie until the day of his death on February 11, 2019. Through his long research career, Briggs stayed at the cutting edge by re-inventing himself from a plant physiologist, to biochemist, geneticist, and molecular biologist. He made numerous discoveries, including the LOV-domain photoreceptor phototropin. Winslow Briggs, who was also a naturalist and gifted pianist, inspired and promoted the work of generations of young scientists – as mentor, colleague and friend.
... Si is beneficial for plants, such as protecting against diseases, insects attacks, reinforcing nutrients and safeguarding under unfavorable conditions like drought, salt or heavy metals toxicity (Debona et al., 2017;Tayyab et al., 2018b). Kutschera and Niklas (2018) highlighted the function of Si in plant biology as "whether silicic acid is an indispensable substance for those plants that contain silica, whether it takes part in the nutritional processes, and what is the relationship that exists between the uptake of silicic acid and the life of the plant?" (Lewin and Reimann, 1969). ...
Drought is considered as one of the significant threats to food security worldwide as it inhibits the growth, yield and quality of economically important crops. An increase in crop yield is considered a tremendous achievement as it will be helpful to meet the current growing demand for food in drought-stressed areas. Silicon (Si) is the second most abundant component in the soil. Recent research has revealed that Si can enhance plant tolerance against drought stress. In addition, application of Si can increase seed germination, underground and above ground biomass, photosynthetic pigments, quality and yield of grains. Therefore, we have summarized the importance of Si in improving the drought tolerance in plants. Furthermore, we have explained the Si-mediated mechanisms which led to modifications in gas exchange properties, homeostasis of the nutrient element, synthesis of compatible solute, osmotic adjustments, antioxidant stimulation and enzymatic action in plants under drought stress. We believe that the current study will help in understanding the importance of Si application in plants under drought stress conditions.
Os livros didáticos constituem importante fonte de pesquisa dos professores, incluindo, por exemplo, temas relacionados à história da Teoria Celular. Nessa perspectiva, esta pesquisa analisou como os livros didáticos de biologia, do ensino médio, têm trabalhado as questões históricas relacionadas à Teoria Celular. Para isso, foram selecionados três livros didáticos, os quais foram analisados para verificar como os autores utilizaram a História da Ciência, ao contextualizarem temas relacionados à Teoria Celular. Trata-se de uma pesquisa qualitativa, com análise bibliográfica e documental. Como metodologia de análise, empregamos a Análise de Conteúdo, estabelecendo, como categorias, algumas das visões deformadas apresentadas por Gil Pérez e colaboradores. Os resultados revelaram que muitas das visões deformadas de ciência são reproduzidas nos livros didáticos.
Julius Sachs (1832–1897), who has been quite rightly called “the father of plant physiology,” was a German physiologist of international standing, whose research interests contributed to virtually every branch of the plant sciences, and whose work presaged plant molecular biology and systems biology. Here, we focus on one of his last publications, from 1892, wherein he argued that the term “cell” (Zelle) is misleading and should be replaced by “energid” (Energide), which he defined as “a nucleus together with the corresponding protoplasm that is governed by it,” based on his observations of coenocytic algae such as Caulerpa whose nuclei “can only control” so much cytoplasm. Although most of his colleagues did not accept this novel terminology for the description of the “basic, minimal living unit” (Elementarorganismus) of animals, plants, and microbes, we argue that the energid concept prefigured the subsequent discovery of mRNA. We also argue that the resistance to the energid concept revolved around a deep-seated philosophical debate between those adhering to cell theory versus organismal theory. The first English translation of the seminal work by Sachs, “Physiologische Notizen. II. Beiträge zur Zellentheorie. a) Energiden und Zellen,” originally published in Flora (75: 57–67, 1892), is provided as a separate article in this volume as part of the journal’s “Classics in Biological Theory” collection (https://doi.org/10.1007/s13752-022-00399-w); the original German version is available here as supplementary material in the online version of this article.
One century ago, the German chemist and botanist Wilhelm Pfeffer (1845–1920) died, shortly after finishing his last lecture at the University of Leipzig. Pfeffer was, together with Julius Sachs (1832–1897), the founder of modern plant physiology. In contrast to Sachs, Pfeffer’s work was exclusively based on the principles of physics and chemistry, so that with his publications, notably the ca. 1.600 pages-long Handbuch der Pflanzenphysiologie (2. ed., Vol. I/II; 1897/1904), experimental plant research was founded. Here we summarize Pfeffer’s life and work with special emphasis on his experiments on osmosis, plant growth in light vs. darkness, gravitropism, cell physiology, photosynthesis and leaf movements. We document that Pfeffer was the first to construct/establish constant temperature rooms (growth chambers) for seed plants. Moreover, he pioneered in outlining the carbon-cycle in the biosphere, and described the effect of carbon dioxide (CO2)-enhancement on assimilation and plant productivity. Wilhelm Pfeffer pointed out that, at ca. 0.03 vol% CO2 (in 1900), photosynthesis is sub-optimal. Accordingly, due to human activities, anthropogenic CO2 released into the atmosphere promotes plant growth and crop yield. We have reproduced Pfeffer’s classical experiments on the role of CO2 with respect to plant development, and document that exhaled air of a human (ca. 4 vol% CO2) strongly promotes growth. We conclude that Pfeffer not only acted as a key figure in the establishment of experimental plant physiology. He was also the discoverer of the phenomenon of CO2-mediated global greening and promotion of crop productivity, today known as the “CO2-fertilization-effect”. These topics are discussed with reference to climate change and the most recent findings in this area of applied plant research.
Sustainable production of high-quality food is one of today’s major challenges of agriculture. To achieve this goal, a better understanding of plant physiological processes and a more integrated approach with respect to current agronomical practices are needed. In this review, various examples of cooperation between integrative plant physiology and agronomy are discussed, and this demonstrates the complexity of these interrelations. The examples are meant to stimulate discussions on how both research areas can deliver solutions to avoid looming food crises due to population growth and climate change. In the last decades, unprecedented progress has been made in the understanding of how plants grow and develop in a variety of environments and in response to biotic stresses, but appropriate management and interpretation of the resulting complex datasets remains challenging. After providing an historical overview of integrative plant physiology, we discuss possible avenues of integration, involving advances in integrative plant physiology, to sustain plant production in the current post-omics era. Finally, recommendations are provided on how to practice the transdisciplinary mindset required, emphasising a broader approach to sustainable production of high-quality food in the future, whereby all those who are involved are made partners in
knowledge generation processes through transdisciplinary cooperation.
Actin cytoskeleton was discovered some 70 years ago, and it is well known to be responsible for cellular transport phenomena and contractilities, with animal muscles representing the most obvious example. This ancient cytoskeletal system is present in all eukaryotic cells, responsible for all kinds of intracellular motilities. For example, the synaptic vesicle recycling also relies on the actin cytoskeleton, which supports all types of membranes structurally and functionally. Action potentials are fundamental for the long-distance signaling in both animals and plants. Although it is not generally appreciated, action potentials are mechanistically and functionally interlinked with the actin cytoskeleton associated with membranes. In both animals and plants, the inherent bioelectricity of membranes is closely linked with the actin cytoskeleton. Despite the fundamental importance of this phenomenon, it remains to be under-investigated, and future studies will be needed to illuminate the elusive electrochemical and bioelectric nature of cellular life.
In 1905, Constantin S. Mereschkowsky (1855–1921) proposed that the green organelles (chloroplasts) of algae and land plants evolved from ancient, once free-living cyanobacteria. This endosymbiotic hypothesis was based on numerous lines of evidence. In a 1910 paper, Mereschkowsky argued that the time has come to introduce a new theory on the origin of living beings; since Darwin’s era, so many new findings have accumulated that now an alternative, anti-selectionist theory of evolution has to be established. Based on the principle of symbiosis (i.e., the union of two different organisms whereby both partners mutually benefit), Mereschkowsky coined the term “symbiogenesis theory,” which is based on an analogy between the feeding process of amoebae and cellular events that may have occurred in the ancient oceans. Mereschkowsky’s symbiogenesis hypothesis explains the origin of chloroplasts from archaic cyanobacteria, with respect to plant evolution. In 1927, the Russian cytologist Ivan E. Wallin (1883–1969) proposed that the mitochondria of eukaryotic cells are descendants of ancient, once free-living bacteria. Here, I outline the origin and current status of the Mereschkowsky–Wallin concept of symbiogenesis (primary and secondary endosymbiosis) and explain why it is compatible with the Darwin–Wallace principle of natural selection, which is described in detail. Nevertheless, largely due to the work of Lynn Margulis (1938–2011), symbiogenesis is still considered today as an Anti-Darwinian research program. I will summarize evidence indicating that symbiogenesis, natural selection, and the dynamic Earth (plate tectonics) represent key processes that caused major macro-evolutionary transitions during the 3500-million-year-long history of life on Earth.
The origin of eukaryotes is one of the big questions in evolution. Many different ideas about eukaryote origin currently coexist in the literature that weight the evolutionary significance of mitochondria differently. Gradualist theories depict the origin of eukaryotic cell complexity and the origin of mitochondria as independent, unrelated processes that occurred in series. Symbiogenic theories depict the origin of eukaryotic cell complexity as emerging from the symbiosis that gave rise to mitochondria. Since it was introduced over 100 years ago, the idea of symbiogenesis has been controversial. It posits that rarely in Earth history, and only in microbes, a mechanism of evolution has operated in nature that forges new taxa at highest ranks via the endosymbiotic combination of two cells into one. The role of symbiogenesis in evolution versus the gradualist paradigm of constant and incremental mutation accumulation is still debated. A perceived problem with symbiogenesis is that it operates discontinuously and rarely during evolution. Moreover when it does operate, major evolutionary transitions, such as the origin of eukaryotes, plants, and algal groups are the outcome. Here I briefly contrast current symbiogenic and gradualist views on eukaryote origin regarding phagocytosis, the host for mitochondria, eukaryote anaerobes, the eukaryote endomembrane system, gene transfers from organelles, lateral gene transfer, and the number of endosymbiotic partners in eukaryote history. Special attention is given to energy conservation in mitochondria, which fostered eukaryotic complexity by lifting energetic constraints on protein synthesis in mitochondrion bearing cells relative to their prokaryotic ancestors. © 2017, Croatian Society of Natural Sciences. All rights reserved.
In species reproducing both sexually and asexually clones are often more common in recently established populations. Earlier studies have suggested that this pattern arises due to natural selection favouring generally or locally successful genotypes in new environments. Alternatively, as we show here, this pattern may result from neutral processes during species' range expansions. We model a dioecious species expanding into a new area in which all individuals are capable of both sexual and asexual reproduction, and all individuals have equal survival rates and dispersal distances. Even under conditions that favour sexual recruitment in the long run, colonisation starts with an asexual wave. After colonisation is completed, a sexual wave erodes clonal dominance. If individuals reproduce more than one season, and with only local dispersal, a few large clones typically dominate for thousands of reproductive seasons. Adding occasional long-distance dispersal, more dominant clones emerge, but they persist for a shorter period of time. The general mechanism involved is simple: edge effects at the expansion front favour asexual (uniparental) recruitment where potential mates are rare. Specifically, our model shows that neutral processes (with respect to genotype fitness) during the population expansion, such as random dispersal and demographic stochasticity, produce genotype patterns that differ from the patterns arising in a selection model. The comparison with empirical data from a postglacially established seaweed species (Fucus radicans) shows that in this case a neutral mechanism is strongly supported. This article is protected by copyright. All rights reserved.
Peroxisomal β-oxidation in plants is essential for mobilization of storage oil in seed-oil storing plants, such as Arabidopsis thaliana. In plants, degradation of fatty acids occurs exclusively in peroxisomes via β-oxidation, driving seedling growth and development upon germination. Thus, the determination of storage oil breakdown rates is a useful approach to investigate defects in peroxisomal β-oxidation. Here we describe an acid catalyzed derivatization process of fatty acids representing a fast and efficient procedure to generate high yields of fatty acid methyl esters (FAMEs). The subsequent analysis by gas chromatography coupled to mass spectrometry (GC-MS) allows the quantification of total fatty acid content. The results provide detailed information of the complete storage oil breakdown process via peroxisomal β-oxidation during seedling growth.
Myxomycetes: Biology, Systematics, Biogeography, and Ecology is a comprehensive overview of the body of accumulated knowledge that now exists on myxomycetes. Its broad scope takes an integrated approach to the knowledge of this organismal group, considering a number of important aspects of their genetics and molecular phylogeny. It also treats myxomycetes as a distinct group from fungi, and includes molecular information that discusses the systematics and evolutionary pathways of the group. Additionally, biomedical and engineering applicability is discussed, thus expanding the audience and use of the book in a multidisciplinary context. The book provides an authoritative resource for students, researchers and educators interested in the fields of protistology, microbial ecology, molecular microbiology, biogeography, mycology, biodiversity, and evolutionary biology, and will also interest the amateur naturalist and biologist.
For a century the green alga Coleochaete has figured prominently in considerations of the origins of land plants (embryophytes). Certain of its advanced features contributed to Bower's (1908) theories on the origin of the land plant sporophyte by intercalation. Though Bower's ideas were disputed in later years, recent investigations of Coleochaete and other green algae have lent strong support to them. At present it appears that further study of Coleochaete and other charophycean algae may contribute much to our understanding of how a number of plant features, including reproductive ones, originated.
Friederich Wilhelm Benedikt Hofmeister (1824-1877) stands as one of the true giants in the history of biology and belongs in the same pantheon as Darwin and Mendel. Yet by comparison, he is virtually unknown. If he is known at all, it is for his early work on flowering plant embryology and his ground-breaking discovery of the alternation of generations in plants, which he published at age 27 in 1851. Remarkable as the latter study was, it was but a prelude to the more fundamental contributions he was to make in the study of plant growth and development expressed in his books on plant cell biology (Die Lehre von der Pfanzenzelle, 1867) and plant morphology (Allgemeine Morphologie der Gewächse, 1868). In this article we review his remarkable life and career, highlighting the fact that his scientific accomplishments were based largely on self-education in all areas of biology, physics, and chemistry. We describe his research accomplishments, including his early embryological studies and their influence on Mendel's genetic studies as well as his elucidation of the alternation of generations, and we review in detail his cell biology and morphology books. It is in the latter two works that Hofmeister the experimentalist and biophysicist is most manifest. Not only did Hofmeister explore the mechanisms of cytoplasmic streaming, plant morphogenesis, and the effects of gravity and light on their development, but in each instance he developed a biophysical model to integrate and interpret his wealth of observational and experimental data. Because of the lack of attention to the cell and morphology books, Hofmeister's true genius has not been recognized. After studying several evaluations of Hofmeister by contemporary and later workers, we conclude that his reputation became eclipsed because he was so far ahead of his contemporaries that no one could understand or appreciate his work. In addition, his basically organismic framework was out of step with the more reductionistic cytogenetic work that later came in vogue. We suggest that the translation of the cell and morphology books in English would help re-establish him as one of the most notable scientists in the history of plant biology.
Contents 1 I. 1 II. 2 III. 5 IV. 8 V. 11 VI. 12 13 13 References 13 SUMMARY: Stomatal guard cells control leaf CO2 intake and concomitant water loss to the atmosphere. When photosynthetic CO2 assimilation is limited and the ratio of CO2 intake to transpiration becomes suboptimal, guard cells, sensing the rise in CO2 concentration in the substomatal cavity, deflate and the stomata close. Screens for mutants that do not close in response to experimentally imposed high CO2 atmospheres identified the guard cell-expressed Slowly activating anion channel, SLAC1, as the key player in the regulation of stomatal closure. SLAC1 evolved, though, before the emergence of guard cells. In Arabidopsis, SLAC1 is the founder member of a family of anion channels, which comprises four homologues. SLAC1 and SLAH3 mediate chloride and nitrate transport in guard cells, while SLAH1, SLAH2 and SLAH3 are engaged in root nitrate and chloride acquisition, and anion translocation to the shoot. The signal transduction pathways involved in CO2 , water stress and nutrient-sensing activate SLAC/SLAH via distinct protein kinase/phosphatase pairs. In this review, we discuss the role that SLAC/SLAH channels play in guard cell closure, on the one hand, and in the root-shoot continuum on the other, along with the molecular basis of the channels' anion selectivity and gating.