4H1W:
reference: The sarcolipin-bound calcium pump stabilizes calcium sites exposed to the cytoplasm., Winther AM, Bublitz M, Karlsen JL, Moller JV, Hansen JB, Nissen P, Buch-Pedersen MJ, Nature. 2013 Mar 14;495(7440):265-9. doi: 10.1038/nature11900. Epub 2013 Mar 3. PMID: 23455424

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