{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nAlthough the query requested a summary of SNORD114‑2, none of the provided abstracts mention this small nucleolar RNA. Instead, the literature presented focuses extensively on the TASK‑2 (also known as KCNK5 or K2P5.1) two‐pore domain potassium channel and its multifaceted role in physiology. TASK‑2 channels are portrayed as crucial pH‐sensitive “leak” K⁺ channels that contribute to CO₂/H⁺ chemosensitivity in brainstem respiratory circuits and to renal bicarbonate reabsorption, thereby maintaining acid–base homeostasis, as well as to the regulation of cell volume in different tissues."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "1", "end_ref": "7"}]}, {"type": "t", "text": " \n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nAt the mechanistic level, these studies reveal that TASK‑2 channels are intricately gated by both extracellular and intracellular pH changes. They are activated by alkalinization and exhibit dynamic modulation via processes such as protonation of key extracellular arginine or lysine residues, sensitivity to intracellular ions (e.g. Na⁺), and regulation by phosphatidylinositol 4,5‑bisphosphate and G‑protein βγ subunits. Structural analyses, including recent cryo‑electron microscopy, further define dual gating sites—one at the inner pore and another at the selectivity filter—that underpin the channel’s unique response to pH and its rapid conformational transitions."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "8", "end_ref": "14"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nMoreover, TASK‑2 channels emerge as important regulators beyond classic epithelial roles. Their activity modulates cellular processes in sensory systems (as evidenced by their required function in maintaining endocochlear potential and hearing) and in immune cells, where upregulation under hypoxic or receptor‐stimulated conditions contributes to the regulation of Ca²⁺ influx, the orchestration of apoptotic volume decrease, and even the organization of the immunological synapse. These findings also delineate that, although TASK‑2 is dispensable for certain anesthetic actions, its modulation via various signaling pathways (including HIF‑1α–dependent mechanisms) may have implications for autoimmune conditions."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "15", "end_ref": "19"}]}, {"type": "t", "text": "\n"}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Karin M Gerstin, Diane H Gong, Mona Abdallah, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Mutation of KCNK5 or Kir3.2 potassium channels in mice does not change minimum alveolar anesthetic concentration."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Anesth Analg (2003)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1213/01.ANE.0000056921.15974.EC"}], "href": "https://doi.org/10.1213/01.ANE.0000056921.15974.EC"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "12707131"}], "href": "https://pubmed.ncbi.nlm.nih.gov/12707131"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Herve Barriere, Radia Belfodil, Isabelle Rubera, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Role of TASK2 potassium channels regarding volume regulation in primary cultures of mouse proximal tubules."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "J Gen Physiol (2003)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1085/jgp.200308820"}], "href": "https://doi.org/10.1085/jgp.200308820"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "12860925"}], "href": "https://pubmed.ncbi.nlm.nih.gov/12860925"}]}, {"type": "r", "ref": 3, "children": [{"type": "t", "text": "Richard Warth, Hervé Barrière, Pierre Meneton, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Proximal renal tubular acidosis in TASK2 K+ channel-deficient mice reveals a mechanism for stabilizing bicarbonate transport."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Proc Natl Acad Sci U S A (2004)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1073/pnas.0400081101"}], "href": "https://doi.org/10.1073/pnas.0400081101"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "15141089"}], "href": "https://pubmed.ncbi.nlm.nih.gov/15141089"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "Michael J Morton, Sarah Chipperfield, Abdulrahman Abohamed, et al. 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"}, {"type": "b", "children": [{"type": "t", "text": "Phosphatidylinositol (4,5)-bisphosphate dynamically regulates the K"}, {"type": "a", "children": [{"type": "t", "text": "sub"}], "href": "sub"}, {"type": "t", "text": "2P"}, {"type": "a", "children": [{"type": "t", "text": "/sub"}], "href": "/sub"}, {"type": "t", "text": " background K"}, {"type": "a", "children": [{"type": "t", "text": "sup"}], "href": "sup"}, {"type": "t", "text": "+"}, {"type": "a", "children": [{"type": "t", "text": "/sup"}], "href": "/sup"}, {"type": "t", "text": " channel TASK-2."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Sci Rep (2017)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1038/srep45407"}], "href": "https://doi.org/10.1038/srep45407"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "28358046"}], "href": "https://pubmed.ncbi.nlm.nih.gov/28358046"}]}, {"type": "r", "ref": 17, "children": [{"type": "t", "text": "Kyoko Endo, Hiroaki Kito, Ryo Tanaka, et al. 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