Core Viewpoint - The research indicates that sleep is essential for preventing the disruption of the brain phosphoproteome, which is crucial for survival [2][3]. Group 1: Importance of Sleep - Sleep is an indispensable behavior preserved across all animal species, and long-term sleep deprivation (Pr-SD) can lead to mortality in various species [1]. - The core molecular basis linking sleep deprivation-induced lethality and sleep homeostasis in mammals remains unclear [8]. Group 2: Mechanisms and Functions of Sleep - Numerous factors affecting sleep duration or quality have been reported, including biological clock genes, neural circuits, specific kinase signaling pathways, and neurotransmitters [6]. - Research has identified several functions related to sleep, such as cognition, metabolic waste clearance, metabolism, and immune function [6]. Group 3: Research Methodology - The Disk-over-water (DOW) method is utilized to study sleep deprivation by placing animals on a disk above water, forcing them to stay awake [10]. - The study observed an "irreversible point" (PONE) state in rats during DOW experiments, characterized by irreversible mortality even after sleep deprivation is terminated [11]. Group 4: Findings on PONE State - Analysis of the PONE state revealed that the balance of the brain phosphoproteome is critical for sleep regulation and the mortality caused by Pr-SD [12]. - Mice in the PONE state were unable to enter natural sleep, and their brain phosphoproteome exhibited significant disruption, closely related to the PONE state rather than the duration of sleep deprivation [13]. Group 5: Implications for Sleep and Health - Dysfunction in brain kinases or phosphatases affects the development of the PONE state and leads to corresponding sleep abnormalities [14]. - Restorative sleep of 80 minutes daily can significantly delay cognitive decline and restore the brain phosphoproteome [14]. - The findings suggest that sleep is vital for maintaining the homeostasis of the brain phosphoproteome, and its disruption may influence lethality caused by long-term sleep deprivation [14].

Core Viewpoint - The research reveals the mechanism of how certain sea slugs, specifically Sacoglossan, integrate chloroplasts from algae into their cells, allowing them to perform photosynthesis, a process previously thought to be exclusive to plants [5][11]. Group 1 - The study published in the journal Cell discusses the integration of stolen chloroplasts in sea slugs for animal photosynthesis [5]. - Sacoglossan sea slugs can selectively retain chloroplasts from ingested algae, maintaining their photosynthetic capabilities for up to a year [7]. - The newly discovered organelle, named "kleptosome," encapsulates the chloroplasts, providing an environment conducive to photosynthesis [8]. Group 2 - The kleptosome utilizes ATP-sensitive ion channels to create an internal environment that supports chloroplast longevity and function [10]. - When the sea slugs are deprived of food, they change color from green to orange, indicating the digestion of stored chloroplasts for nutrients [10]. - The findings highlight the evolutionary adaptability of animal cells under pressure, showcasing convergent evolution in other photosynthetic animals like corals and sea anemones [11]. Group 3 - The research emphasizes the long-term acquisition and evolutionary integration of symbiotic organelles into complex cellular structures [13]. - The initial interest in the study stemmed from a misconception about sea slugs consuming corals, leading to the discovery of their unique photosynthetic abilities [13].

Core Viewpoint - The research on the human sweet taste receptor reveals its unique asymmetric dimer structure and ligand recognition mechanism, providing a molecular basis for the design of new artificial sweeteners and drug development strategies targeting sweet receptors [4][9]. Group 1: Research Findings - The study published in Nature characterizes the high-resolution three-dimensional structure of the human sweet taste receptor in both apo and sucralose-bound states [4][6]. - The research team identified that sucralose binds specifically to the Venus flytrap domain of TAS1R2, highlighting the receptor's asymmetric dimer structure [7][9]. - The study utilized mutagenesis and molecular dynamics simulations to depict the recognition pattern of sweeteners within TAS1R2, revealing conformational changes and unique activation mechanisms upon ligand binding [7][9]. Group 2: Research Team and Contributions - The research was conducted by a team from ShanghaiTech University, with key contributors including researchers Huatian and Zhijie Liu, along with several doctoral and postdoctoral researchers [9]. - This study marks another breakthrough in the field of chemical sensing molecular mechanisms, following previous reports on bitter taste receptors [9].

Core Viewpoint - The article discusses the significant findings of a research study on long non-coding RNA (lncRNA), specifically the structure of natural RNA nanocages formed by the ROOL RNA, which may have implications for research and therapeutic applications [2][3][11]. Group 1: Research Findings - The study identified two types of natural RNA nanocages formed by the long non-coding RNA ROOL found in bacterial and phage genomes [5]. - The cryo-EM structure revealed that the ROOL RNA forms an octameric nanocage with a diameter of 28 nanometers and an axial length of 20 nanometers, featuring a disordered region in its internal cavity [7]. - The assembly of the nanocage involves a chain exchange mechanism, leading to the formation of a quaternary kissing loop [7]. Group 2: Structural Characteristics - The octameric structure is stabilized by numerous tertiary and quaternary interactions, including the proposed "A-minor staple" [7]. - The isolated ROOL monomer structure was observed at a resolution of approximately 3.2 Å, indicating the complexity of the nanocage assembly [7]. Group 3: Potential Applications - The research suggests that ROOL RNA, when fused with RNA aptamers, tRNA, or microRNA, can maintain its structure and form a nanocage capable of radially displaying cargo [9]. - These findings may lead to the design of novel RNA nanocages for use as RNA carriers in research and therapeutic applications [11].

Core Insights - A new study from the United States reveals that the Plasmodium falciparum can evade the human immune system for extended periods by shutting down key genes, providing new insights into chronic asymptomatic malaria infections [1][2] Group 1: Malaria and Its Challenges - Malaria is a severe infectious disease caused by Plasmodium, transmitted to humans through mosquito bites [1] - The difficulty in eradicating malaria is partly due to the ability of Plasmodium falciparum to remain asymptomatic in infected individuals, allowing it to be transmitted by mosquitoes [1] Group 2: Mechanism of Immune Evasion - Plasmodium falciparum relies on a gene family called var, consisting of approximately 60 genes, to avoid detection by the immune system [1] - When a var gene is activated, the resulting protein allows infected red blood cells to adhere to blood vessel walls, evading filtration by the spleen [1] - The immune system produces antibodies against the activated protein within about a week, prompting the parasite to switch to another var gene to prolong the infection [1][2] Group 3: Research Findings - The study utilized single-cell sequencing technology to analyze how individual Plasmodium falciparum regulate var gene expression [2] - While most parasites activate only one var gene at a time, some can activate two or three simultaneously, and others may not express any var genes at all [2] - Understanding these mechanisms may lead to new strategies for addressing chronic malaria infections [2]

Core Viewpoint - The research published by the team from Southern University of Science and Technology reveals a novel anti-phage immune strategy mediated by bacterial reverse transcriptase DRT9 and non-coding RNA, which synthesizes long poly-A-rich cDNA to defend against phage infection [2][4][5]. Group 1: Mechanism of DRT9 Immune System - DRT9 forms a hexameric complex with upstream non-coding RNA (ncRNA) to mediate anti-phage defense by inducing cell growth arrest during phage infection [4]. - During phage infection, the phage-encoded ribonucleotide reductase NrdAB complex increases intracellular dATP levels, activating DRT9 to synthesize long poly-A-rich single-stranded cDNA, which may capture essential single-stranded DNA binding proteins (SSB proteins) of the phage and inhibit its proliferation [4]. - The research team determined the cryo-electron microscopy structure of the DRT9-ncRNA hexameric complex, providing insights into its cDNA synthesis mechanism [4]. Group 2: Implications of the Findings - These findings highlight the diversity of reverse transcriptase-based antiviral defense mechanisms, expanding the understanding of the biological functions of reverse transcriptases [5]. - The research lays a theoretical foundation for developing novel biotechnological tools based on DRT9 [5].