Fenretinide binding to the lysosomal protein saposin D alters ceramide solubilization and hydrolysis.
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ABSTRACT:
SUBMITTER: Milliken BT
PROVIDER: S-EPMC7513591 | biostudies-literature | 2020 Sep
REPOSITORIES: biostudies-literature
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Fenretinide binding to the lysosomal protein saposin D alters ceramide solubilization and hydrolysis.
Milliken Brandon T BT Melegari Lindy L Smith Gideon L GL Grohn Kris K Wolfe Aaron J AJ Moody Kelsey K Bou-Abdallah Fadi F Doyle Robert P RP
RSC medicinal chemistry 20200714 9
Fenretinide is a synthetic retinoid pharmaceutical linked to ceramide build-up <i>in vivo</i>. Saposin D is an intralysosomal protein necessary for ceramide binding/degradation. We show, <i>via</i> electronic absorption spectroscopy, fluorescence spectroscopy, and ceramide hydrolysis assays, that fenretinide is bound by saposin D {<i>K</i> <sub>a</sub> = (1.45 ± 0.49) × 10<sup>5</sup> M<sup>-1</sup>}, and affects ceramide solubilization/degradation. ...[more]
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