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presence here is not a separate transport or causal claim."}]},"contexts":[{"dimension":"compartment_description","value_text":"ER membrane","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Purified recombinant human SERCA2b; cryo-EM and ATPase characterization","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Evidence specifies ATP2A2 splice isoform SERCA2b; kinetic properties should not be assigned to every SERCA isoform.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Calcium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"calcium","display_name":"Calcium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"SERCA2b uses ATP to refill ER calcium stores.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[ca-zhang2020] Cryo-EM structures of SERCA2b reveal the mechanism of regulation by the luminal extension tail (2020). https://pubmed.ncbi.nlm.nih.gov/32851169/ DOI: 10.1126/sciadv.abb0147","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"research_relationship_category","value_text":"transport","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Recombinant SERCA2b","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"transport_effect","value_text":"lowers","comparator":null,"unit":null,"notes":"Recorded as sequestration of cytosolic calcium into the ER.","entity":null},{"dimension":"transport_or_reaction_direction","value_text":"Cytosol to ER lumen","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"transport_pool","value_text":"cytosolic calcium","comparator":null,"unit":null,"notes":"Recorded as sequestration of cytosolic calcium into the ER.","entity":null}],"evidence":[{"id":"b6efe0b6-29e3-575e-bd9c-d3c7844a57de","evidence_kind":"source_excerpt","locator":"Lines 571-583","start_line":571,"end_line":583,"excerpt":"### ca-serca2b-er-uptake\nHuman SERCA2b couples its ATPase cycle to sequestration of cytosolic calcium into the ER.\nCondition category: normal\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: SERCA2b uses ATP to refill ER calcium stores.\norganism: Homo sapiens\ntissue_or_cell_type: Recombinant SERCA2b\nexperimental_model: Purified recombinant human SERCA2b; cryo-EM and ATPase characterization\nlimitations: Evidence specifies ATP2A2 splice isoform SERCA2b; kinetic properties should not be assigned to every SERCA isoform.\nresearch_relationship_category: transport\ntransport_or_reaction_direction: Cytosol to ER lumen\ncompartment_description: ER membrane\n[ca-zhang2020] Cryo-EM structures of SERCA2b reveal the mechanism of regulation by the luminal extension tail (2020). https://pubmed.ncbi.nlm.nih.gov/32851169/ DOI: 10.1126/sciadv.abb0147","model_system":"Purified recombinant human SERCA2b; cryo-EM and ATPase characterization","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [ca-zhang2020] Cryo-EM structures of SERCA2b reveal the mechanism of regulation by the luminal extension tail (2020). https://pubmed.ncbi.nlm.nih.gov/32851169/ DOI: 10.1126/sciadv.abb0147","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"3c083fa0-59c6-50e9-af42-678d0e3c1006","stable_key":"import-434e1e27-eb90-583a-956b-62472726ffba","title":"Calcium: mechanism-first literature curation (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"965c934d6b147f2b62f8d45ce6d7a87681a600bfe5c46a585b4704889afd3fc1","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}