PLoS Biology最新文献

Energy metabolism involves a series of biochemical reactions that generate ATP, utilizing substrates such as glucose and oxygen supplied via cerebral blood flow. Energy substrates are metabolized in multiple interrelated pathways that are cell- and organelle-specific. These pathways not only generate energy but are also fundamental to the production of essential biomolecules required for neuronal function and survival. How these complex biochemical processes are spatially distributed across the cortex is integral to understanding the structure and function of the brain. Here, using curated gene sets and whole-brain transcriptomics, we generate maps of five fundamental energy metabolic pathways: glycolysis, pentose phosphate pathway, tricarboxylic acid cycle, oxidative phosphorylation and lactate metabolism. We find consistent divergence between primarily energy-producing and anabolic pathways, particularly in unimodal sensory cortices. We then explore the spatial alignment of these maps with multi-scale structural and functional attributes, including metabolic uptake, neurophysiological oscillations, cell type composition, laminar organization and macro-scale connectivity. We find that energy pathways exhibit unique relationships with the cellular and laminar organization of the cortex, pointing to the higher energy demands of large pyramidal cells and efferent projections. Finally, we show that metabolic pathways exhibit distinct developmental trajectories from the fetal stage to adulthood. The primary energy-producing pathways peak in childhood, while the anabolic pentose phosphate pathway shows greater prenatal expression and declines throughout life. Together, these results highlight the rich biochemical complexity of energy metabolism organization in the brain.

[This corrects the article DOI: 10.1371/journal.pbio.3003413.].

Retinal organoids have become important models for studying development and disease, yet stochastic heterogeneity in the formation of cell types, tissues, and phenotypes remains a major challenge. This limits our ability to precisely experimentally address the early developmental trajectories towards these outcomes. Here, we utilize deep learning to predict the differentiation path and resulting tissues in retinal organoids well before they become visually discernible. Our approach effectively bypasses the challenge of organoid-related heterogeneity in tissue formation. For this, we acquired a high-resolution time-lapse imaging dataset comprising about 1,000 organoids and over 100,000 images enabling precise temporal tracking of organoid development. By combining expert annotations with advanced image analysis of organoid morphology, we characterized the heterogeneity of the retinal pigmented epithelium (RPE) and lens tissues, as well as global organoid morphologies over time. Using this training set, our deep learning approach accurately predicts the emergence and size of RPE and lens tissue formation as well as similarities in overall organoid morphology on an organoid-by-organoid basis at early developmental stages, refining our understanding of when early lineage decisions are made. This approach advances knowledge of tissue and phenotype decision-making in organoid development and can inform the design of similar predictive platforms for other organoid systems, paving the way for more standardized and reproducible organoid research. Finally, it provides a direct focus on early developmental time points for in-depth molecular analyses, alleviated from confounding effects of heterogeneity.

Immunometabolism describes more than just metabolic shifts in immune cells. A new collection of articles shines a light on the many facets of immunometabolism, exploring the effects of molecular, cellular, and systemic metabolic mechanisms in health and disease.

The high prevalence of cancer immunotherapy resistance, coupled with substantial tumor heterogeneity, underscores the urgent need for innovative therapeutic targets. A deeper understanding of immunoregulatory mechanisms would provide new targets and combination therapeutic strategies for tumor therapy. In this study, we demonstrate that HSD17B12 enhances anti-tumor immunity and represents a promising therapeutic target. Mechanistically, HSD17B12 promotes lysosome-dependent degradation of PD-L1 via the VAC14 and ESCRT complexes across various malignancies, regardless of its 3-ketoacyl-CoA reductase activity. HSD17B12-deficient cells displayed PD-L1 accumulation in both tumor cells and exosomes, reducing T cell-mediated cytotoxicity. Notably, we found a significant negative correlation between HSD17B12 and PD-L1 expression in colorectal cancer tissues. Furthermore, high HSD17B12 expression in CRC correlated with increased infiltration of cytotoxic T cells. Based on these findings, we designed a peptide, HSD-CC1-NPGY, which effectively reduces PD-L1 expression in cells and suppresses tumor growth in a mouse model. Overall, our results establish HSD17B12 as an important regulator of anti-tumor immunity and a promising therapeutic target for cancer treatment.

Interferons (IFNs) are potent antiviral cytokines that are rapidly activated when infected cells sense a virus, but continued IFN production following acute infection is linked to impaired recovery. IFNs protect against infection by inducing a suite of antiviral effectors in IFN receptor-expressing cells via JAK/STAT signaling. However, how IFNs curtail tissue repair is not fully understood. Here, we studied the effects of Type III IFNs (IFNλ1 and IFNλ2) and Type I IFN (IFNβ) on tissue repair functions of human bronchial epithelial cells (HBEC). We show that both Type III IFNs and IFNβ reduce bronchial epithelial cell migration and proliferation through a common upstream mechanism: activation of LATS1, a kinase best known for limiting organ growth as part of the Hippo signaling pathway. Mechanistically, Type III IFN or IFNβ curtailed wound healing by triggering phosphorylation of LATS1 via JAK activity, bypassing activation of MST1/2, the canonical activator of LATS1 in the Hippo pathway. Further experiments showed that distinct signaling pathways lead to LATS1 and STAT1 phosphorylation downstream of IFN receptor signaling. STAT1 was dispensable for IFN-mediated LATS1 phosphorylation and suppression of tissue repair, although as expected STAT1 was required for IFN-mediated protection from rhinovirus or influenza infection. Dose-response curve experiments revealed that higher concentrations of IFN were required to trigger LATS1 phosphorylation compared to STAT1 phosphorylation. Consistently, during rhinovirus or influenza virus infection of organotypic HBEC cultures, we observed phosphorylation of both LATS1 and STAT1, but with different kinetics, with LATS1 activation showing earlier resolution compared to STAT1 activation. These results provide a conceptual framework for understanding how IFN receptor signaling differentially controls epithelial functions required for tissue repair and antiviral defense, and inform efforts to target pathological effects of IFNs following viral infection and in other high IFN states.

The clearance of mitochondria by autophagy (mitophagy) is important for cell health. Mutations in genes that are required for mitophagy, including Vps13D, PINK1, and Parkin, are associated with movement disorders, but gaps exist in our understanding of how Vps13D regulates mitophagy. Here, we identify Mtch (MTCH2 in humans) as a regulator of mitophagy based on a relationship with Vps13D during developmentally programmed mitophagy in Drosophila intestine enterocyte cells. Similar to Vps13D mutant cells, Mtch mutant cells fail to clear mitochondria and possess elevated markers of autophagy. Genetic and molecular experiments reveal that Mtch and Vps13D function in a mitophagy pathway with PINK1, Parkin, and the mitophagy receptor BNIP3. Unlike Vps13D and Parkin mutant cells, Mtch is required for proper expression of the tail-anchored protein BNIP3. Thus, the tail-anchored protein insertase function of Mtch/MTCH2 likely explains how these proteins possess multiple cell context-specific functions.

Somatic cell nuclear transfer (SCNT) is a valuable tool in regenerative medicine, yet its efficiency remains limited by epigenetic reprogramming barriers that have been partially corrected by global regulation of epigenetic enzymes. However, these approaches lack gene locus specificity and may disrupt normal gene regulation. Therefore, new strategies capable of broadly enhancing reprogramming fidelity are needed. Here, we demonstrate that overexpression of the pioneer transcription factor Nr5a2 in mouse SCNT embryos improves both zygotic genome activation and the morula-to-blastocyst transition, two major developmental barriers in SCNT, and enhances birth rates. Mechanistically, Nr5a2 recruits P300 to increase H3K27ac at genes with low expression, restoring transcriptional activity and promoting SCNT embryo development.

Land plants alternate between generations of asexual sporophytes and sexual gametophytes. Unlike seed plants, ferns produce free-living gametophytes that grow independently from their sporophytes. Gametophytes of the model fern Ceratopteris exist in two sex types: hermaphrodites and males. Hermaphrodites maintain meristems and secrete the pheromone antheridiogen, inducing undecided gametophytes to become males. In the absence of antheridiogen, males exhibit developmental plasticity and dynamic cell fate specification by initiating de novo meristems to convert into hermaphrodites. Despite its essential role, the molecular signals governing this process remain unclear. Here, we show that local auxin biosynthesis, dynamically regulated during sex-type conversion, establishes new auxin maxima that are critical for specifying and promoting the proliferation of the meristem progenitor cell (MPC) lineage, ultimately enabling the de novo formation of a multicellular meristem from a single MPC. Time-lapse imaging revealed that upon antheridiogen removal, auxin signaling is specifically activated at the initial site of proliferation in Ceratopteris males, triggering new meristem formation. This auxin signaling subsequently becomes concentrated at the center of the proliferating meristem, aligning with localized auxin biosynthesis and the emergence of the meristem notch. Computationally reconstrued lineage maps further showed that chemical inhibition of CrTAA1 abolishes these dynamic auxin patterns, blocking MPC lineage initiation and its subsequent proliferation. Furthermore, genetic knockout of CrTAA1 via CRISPR-Cas9 phenocopies the effects of chemical inhibition, preventing new meristem formation and disrupting male-to-hermaphrodite conversion. Together, these findings uncover a molecular mechanism underlying sex-type conversion in land plants and highlight the pivotal role of de novo auxin biosynthesis in orchestrating cell fate and proliferation during meristem formation.

Why the human penis is unusually large compared to that of other primates is a long-standing evolutionary question. Sexual selection, through female mate choice and male-male competition, is a likely driver, but confirming this is difficult due to natural covariation among traits. The solution is to experimentally manipulate focal traits to identify targets of selection. Using 343 computer-generated male figures that varied in penis size, height and body shape, we experimentally tested how these traits influence perceived attractiveness and fighting ability. Over 800 participants-both male and female-viewed either life-sized (in-person) or scaled (online) animations and rated the figures. Across both settings, selection analyses revealed consistent directional selection favoring taller men with a more V-shaped body and a larger penis. In both surveys, male participants rated rivals with a larger penis as more sexually competitive and physically threatening. To our knowledge, this is the first experimental evidence that males assess rivals' fighting ability and attractiveness to females based partly on a rival's penis size. Our findings suggest that female choice and male-male competition have jointly favored larger penis size, greater height, and more V-shaped bodies in men.