{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nAlthough none of the provided abstracts mention RNF215 per se, they extensively describe the functions of TRNP1—a DNA‐associated, low‐complexity nuclear protein that plays a critical role in cortical development. In particular, TRNP1 levels control key aspects of cerebral cortex expansion: high levels promote neural stem cell self-renewal and tangential growth, whereas lower levels favor radial expansion through increased production of intermediate progenitors and basal radial glial cells, an effect that can lead to cortical folding. These experiments in the mouse cerebral cortex in vivo illustrate how TRNP1 dosage finely tunes the balance between progenitor maintenance and differentiation, ultimately influencing brain size and architecture."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}, {"type": "p", "children": [{"type": "t", "text": "\nAt the molecular level, TRNP1 is characterized by its intrinsic disordered regions, which enable it to phase separate and interact with multiple nuclear membrane‐less compartments such as nucleoli, nuclear speckles, and regions of condensed chromatin. This ability suggests that TRNP1 not only modulates neural progenitor proliferation but also co-regulates the architecture and function of nuclear subdomains, thereby helping to maintain cells in a self-renewing state. Notably, deletion of conserved regions within TRNP1 disrupts these functions, leading to altered nucleolar and heterochromatin organization as well as changes in cell cycle dynamics."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": ""}, {"type": "p", "children": [{"type": "t", "text": "\nComparative evolutionary analyses further reveal that changes in both the coding and regulatory regions of TRNP1 correlate with increases in brain size and cortical folding among diverse mammals, implying that enhanced TRNP1 activity was likely favored during evolution. In addition, a massively parallel reporter assay identified a cis-regulatory element of TRNP1 that appears to have co-evolved with gyrification in Old World monkeys and apes, reinforcing the link between TRNP1 regulation and cortical complexity."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": ""}, {"type": "p", "children": [{"type": "t", "text": "\nIn contrast to the detailed insights provided for TRNP1, another abstract describes the identification of proMexneurin—a precursor protein that yields peptides with endomorphin-like activity—which seems unrelated to the functions of TRNP1 or RNF215. Its widespread expression in the mouse brain and its capacity to induce CNS activities highlight the diversity of molecular regulators in neural systems, though it does not pertain to the mechanisms discussed above."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "4"}]}]}]}]}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Ronny Stahl, Tessa Walcher, Camino De Juan Romero, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Trnp1 regulates expansion and folding of the mammalian cerebral cortex by control of radial glial fate."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cell (2013)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.cell.2013.03.027"}], "href": "https://doi.org/10.1016/j.cell.2013.03.027"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "23622239"}], "href": "https://pubmed.ncbi.nlm.nih.gov/23622239"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Miriam Esgleas, Sven Falk, Ignasi Forné, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Trnp1 organizes diverse nuclear membrane-less compartments in neural stem cells."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "EMBO J (2020)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.15252/embj.2019103373"}], "href": "https://doi.org/10.15252/embj.2019103373"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "32627867"}], "href": "https://pubmed.ncbi.nlm.nih.gov/32627867"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Zane Kliesmete, Lucas Esteban Wange, Beate Vieth, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Regulatory and coding sequences of TRNP1 co-evolve with brain size and cortical folding in mammals."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Elife (2023)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.7554/eLife.83593"}], "href": "https://doi.org/10.7554/eLife.83593"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "36947129"}], "href": "https://pubmed.ncbi.nlm.nih.gov/36947129"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "Maura E Matus-Ortega, Philippe Leff Gelman, Juan C Calva-Nieves, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Mexneurin is a novel precursor of peptides in the central nervous system of rodents."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "FEBS Lett (2017)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1002/1873-3468.12679"}], "href": "https://doi.org/10.1002/1873-3468.12679"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "28504339"}], "href": "https://pubmed.ncbi.nlm.nih.gov/28504339"}]}]}]}